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Pre-operative fasting guidelines: an update
... In this study we administered 150 ml as it is the volume of water allowed with medication up to 1 hour before general anaesthesia in the Scandinavian guidelines, with no apparent increased incidence of adverse events. 23 Fourth, although agreement of gastric volumes between the baseline scans taken in the fasted state in both protocols were good, there was some variability. This most likely represents normal variability in gastric physiology. ...
... Fasted patients with high residual gastric volumes currently go undetected and there is no evidence that they suffer any adverse consequences. 23 Further study is required, using this established ultrasound protocol, in patients presenting for surgery (with associated increased anxiety) and should include individuals with comorbidities. It would be bene cial to determine whether administering 150 ml water 1 hour before induction of anaesthesia leads to an increased incidence of high-risk ultrasound features. ...
... Current guidance on pre-operative fasting to reduce aspiration risk may result in unnecessary dehydration. We conducted a trial in healthy volunteers of uid restriction (ESA guideline) 1 compared to more liberal uid intake (Scandinavian guideline) 23 to explore the impact on gastric volume. We found that after 30 minutes following water consumption, most participants had a gastric volume that corresponded with a low risk of aspiration. ...
Background
Current guidance on pre-operative fasting for clear fluids to reduce aspiration risk may result in unnecessary dehydration and more liberal fluid regimes are being advocated.
Methods
This randomised single blinded crossover study used an established ultrasound protocol to measure the gastric volume of 15 healthy volunteers following the 2011 European Society of Anaesthesia (ESA) ‘Perioperative Fasting in Adults and Children’ guidelines (nil-by-mouth two hours before induction of anaesthesia) and the 2005 Scandinavian guidelines (150 mL water with medication up to 1 hour before induction of anaesthesia).
Results
We observed that gastric volumes increased following ingestion of water in all individuals compared to their fasted states. Water left the stomach within 30 minutes following ingestion in ten individuals, and within an hour in three individuals (gastric volume < 1.5 ml kg− 1). A reduction in thirst was observed in the group allowed to drink water, whereas hunger and anxiety scores were unaffected.
... Thus, solid food will pass from the gastric ventricle to the duodenum at a constant rate, whilst clear fluids are eliminated exponentially. 5,16,19 This has two important consequences: first, a very large meal will inevitably take a long time to be completely eliminated from the stomachdpossibly more than 8 h if the food was irresistible and the appetite was stronger than the perception of satiety. Thus, regardless of the regimen implemented, for certain groups of patients (i.e. ...
... For example, with a gastric elimination half-life (t 1/2 ) of 10 min, even a 200 ml drink of water or lemonade will be reduced to 25 ml within 30 min of ingestion. 5 With a more conservative t 1/ 2 of 15 min, the residual approaches 50 ml after the same halfhour interval, and less than 25 ml within 1 h. These calculations are corroborated by a study using serial MRI of gastric content volume (GCVw) after ingestion of a sugared fluid, in which the authors report GCVw similar to baseline (overnight fasting) 1 h after ingestion of a limited amount of fluid (3 ml kg À1 ). ...
... 19 Indeed, the SSAI guideline recommends that infant formula (which may be based on cow's milk) may be ingested up to 4 h before anaesthesia. 5 Furthermore, some centres even allow a light meal containing solids, such as bread, up to 4 h in contradiction to current guidelines. A physiological support for this breach is that, whereas a very large meal may remain in the stomach for a long time, a light meal is likely to be eliminated well within a 4 h interval. ...
Paediatric anaesthetic guidelines for the management of preoperative fasting of clear fluids are currently 2 hours. The traditional 2 hours clear fluid fasting time was recommended to decrease the risk of pulmonary aspiration and is not in keeping with current literature. It appears that a liberalised clear fluid fasting regime does not affect the incidence of pulmonary aspiration and in those who do aspirate, the sequelae are not usually severe or long-lasting. Fasting for prolonged periods increases thirst and irritability and results in detrimental physiological and metabolic effects. With a 1 hour clear fluid policy, there is no increased risk of pulmonary aspiration. There is less nausea and vomiting, thirst, hunger, and anxiety if allowed a drink closer to surgery. Children appear more comfortable, better behaved and possibly more compliant. In children less than 36 months this has positive physiological and metabolic effects.
A local quality improvement project over an 18 month period identified a mean clear fluid fasting time of 6.3 hours a 2 hour clear fasting policy.
This project gave all children a drink on arrival and incorporated a prompt in the WHO checklist for children later on the list to be offered a drink up until 1 hour prior to general anaesthesia. The change led to a mean fluid fasting time reduced to 3.1 hours with no increased risk of aspiration or cancellations.
This led to a national joint consensus statement supported by the Association of Paediatric Anaesthetists of Great Britain and Ireland, the European Society for Paediatric Anaesthesiology, and L’Association Des Anesthésistes-Réanimateurs Pédiatriques d’Expression Française that unless there is a clear contraindication, it is safe and recommended for all children able to take clear fluids, to be allowed and encouraged to have them up to 1 hour before elective general anaesthesia. Local policy is currently being updated.
... Over the years, the practice of Nil per os (NPO) after midnight before elective surgery has been reconsidered [3]. Long preoperative fasting is linked to post-operative accelerated protein catabolism and increase insulin resistance as markers for stress reactions [4]. ...
... Long preoperative fasting is linked to post-operative accelerated protein catabolism and increase insulin resistance as markers for stress reactions [4]. Nevertheless, extended preoperative fasting is not merely distressing for patients and their families [3,4], but also does not improve clinical outcomes [5,6]. Experimental studies and reviews have consistently shown the safety of clear liquid ingestion up to 2 h before induction of anesthesia in healthy patients without risk factors, and the fact that a longer fluid fast does not necessarily offer any added protection against pulmonary aspiration [1] Retrospective reports have shown that application of the liberalized guidelines for preoperative fasting and fluid intake has not resulted in increased pulmonary aspiration, morbidity or mortality. ...
preoperative fasting aims at minimizing the risk of pulmonary aspiration and national published guidelines are needed to promote shorter durations
... The participants were asked to fast from midnight but were allowed clear fluids up to 2 h before the study. 23 Closed opaque envelopes were prepared using a computer-mediated randomised table. At each visit, the participant ingested 500 ml of the beverage specified in the envelope ( Table 1). ...
... Most current guidelines for preoperative fasting in adults recommend 2 h of fasting for carbohydrate-containing clear fluids and 6 h for a light meal of solids and non-clear fluids. 2,3,23 The recently updated ASA guideline noted that ingestion of carbohydrate-containing clear fluids 2 h before anaesthesia significantly reduces hunger and thirst without increasing the risk of complications, but that there is insufficient data for preoperative fluids containing protein or fat. 2 Non-human milk-based products are regarded as solids. These guidelines would guarantee moderate preoperative fasting times and patient comfort, but several audits have shown that fasting times more than 12 h are not uncommon, which can be detrimental in vulnerable patients. ...
Background
Previous studies demonstrated conflicting results regarding the determinants of gastric emptying for fluids. Our aim was to compare gastric emptying times of fluids with different caloric and nutrient content.
Methods
Healthy adult volunteers underwent gastric ultrasound assessment for 4 h after consuming beverages with different caloric and nutrient content using a crossover design (oat drink with 3% fat [310 kcal], mango juice [310 kcal], oat drink with 0.5% fat [185 kcal], and blackcurrant juice [175 kcal]). Gastric emptying time, gastric content volume, and the area under the curve (AUC) of gastric content volume–time profiles were calculated.
Results
Eight females and eight males completed the study protocol. The mean (sd) gastric emptying times were 89 (32) min for blackcurrant juice, 127 (54) min for oat drink with 0.5% fat, 135 (36) min for mango juice, and 152 (40) min for oat drink with 3% fat. Gastric emptying times were slower for oat drink with 3% fat (P=0.007) and mango juice (P=0.025) than for blackcurrant juice. At 1 h after ingestion, gastric content volume was greater for mango juice (P=0.021) and oat drink with 3% fat (P=0.003) than for blackcurrant juice. The AUC was greater for oat drink with 3% fat than mango juice (P=0.029), oat drink with 0.5% fat (P=0.004), and blackcurrant juice (P=0.002), and for mango juice than blackcurrant juice (P=0.019).
Conclusions
Caloric and nutrient content significantly affected gastric emptying times. A high-calorie fruit juice (mango) exhibited delayed emptying times compared with a low-calorie fruit juice (blackcurrant).
... Currently, the American Society of Anesthesiologists (ASA) recommends a fasting interval of 6 h for solids, 4 h for breast milk, and 2 h for clear liquids. [1] The European Society of Anesthesiology (ESA) [2] and the Scandinavian Society of Anesthesiology and Intensive Care [3] recommend that both children and adults drink clear fluids up to 2 h before surgery. Recently, to reduce the negative consequences of prolonged ...
... Currently, the ASA recommends a 6-h fast for solid foods, 4 h for breast milk, and 2 h for clear liquids [1] to reduce the risk of pulmonary aspiration and the severity of its complications. The ESA [2] and the Scandinavian Society of Anesthesiology and Intensive Care [3] have a similar recommendation and agree that both children and adults should drink clear liquids up to 2 h before surgery. ...
Background:
Gastric ultrasound is an effective, non-invasive method to assess the nature and volume of gastric content in the pediatric population. Recently, the UK, European, and French Pediatric Anesthesia Societies recommend fast for clear fluids in children for 1 h. However, studies showing that 1 h of fasting is safe in the pediatric population are still scarce. This study aims to verify by ultrasound evaluation if 1 h of fasting for clear liquids is sufficient to have an empty stomach before anesthetic induction.
Methodology:
Patients between 11 months and 16 years of age scheduled for elective outpatient surgery were included. A qualitative and quantitative ultrasound evaluation was performed by calculating the cross-sectional area (CSA) of the gastric antrum, 1 h after ingesting a volume of 3 mL/kg of a non-carbonated sports drink, before anesthetic induction.
Results:
Fifty patients were included. The average CSA measured by ultrasound was 2.85 ± 1.64 cm2 with an average calculated total volume of 12.9 ± 11.06 mL. All patients had an empty stomach criterion (calculated volume ≤1.5 mL/kg) during the ultrasound evaluation, with an average of 0.40 ± 0.23 mL/kg. With the qualitative assessment of gastric volume, 19 patients (38%) were classified as grade 0, 31 patients (62%) as grade 1, and none as grade 2.
Conclusion:
One hour of fasting after ingestion of 3 mL/kg of a non-carbonated sports drink is sufficient to meet ultrasound criteria for an empty stomach in a pediatric population undergoing elective outpatient surgery.
... Since the landmark work of Maltby et al. 29 in 1986, much evidence has been accumulated showing that the oral intake of clear fluids up to 2 h before an elective operation is safe also in pediatric patients. 30 decreases the occurrence of post-operative nausea and vomiting, the thirst sensation, and the risk of perioperative dehydration. 35 In this regard, a systematic review of 25 randomized controlled trials involving 2543 children found that pediatric patients who were permitted unlimited clear oral fluids up until 2 h before surgery did not experience problems with gastric content volume or pH levels any more than those who were not allowed fluids for over 6 h. ...
... 35 In this regard, a systematic review of 25 randomized controlled trials involving 2543 children found that pediatric patients who were permitted unlimited clear oral fluids up until 2 h before surgery did not experience problems with gastric content volume or pH levels any more than those who were not allowed fluids for over 6 h. They were also found to be less thirsty and hungry, more comfortable, and better behaved than those who fasted, 30 decreasing moreover the length of hospital stay. 28 According to our analysis, preoperative carbohydrate treatment is a safe implementation before gastrointestinal surgery in pediatric patients, reducing the need for a larger amount of intraoperative fluid volume and for prolonged post-operative intravenous fluid infusion. ...
AimTo systematically review literature and to assess the status of the ERAS protocol in pediatric populations undergoing gastrointestinal surgery.Methods
Literature research was carried out for papers comparing ERAS and traditional protocol in children undergoing gastrointestinal surgery. Data on complications, hospital readmission, length of hospital stay, intraoperative fluid volume, post-operative opioid usage, time to defecation, regular diet, intravenous fluid stop, and costs were collected and analyzed. Analyses were performed using OR and CI 95%. A p value <0.05 was considered significant.ResultsA total of 8 papers met the inclusion criteria, with 943 included patients. There was no significant difference in complication occurrence and 30-day readmission. Differently, length of stay, intraoperative fluid volume, post-operative opioid use, time to first defecation, time to regular diet, time to intravenous fluid stop, and costs were significantly lower in the ERAS groups.ConclusionsERAS protocol is safe and feasible for children undergoing gastrointestinal surgery. Without any significant complications and hospital readmission, it decreases length of stay, ameliorates the recovery of gastrointestinal function, and reduces the needs of perioperative infusion, post-operative opioid administration, and costs.
... While prematurity and cow's milk have shown to slacken the rate of gastric emptying, emptying of infant formula feed is greatly affected by the content in it. [3] Delayed gastric emptying can occur in various situations, and may be divided aetiologically into physiological alterations, disease alterations, and intake of drugs. Severe pain and anxiety are well known reasons for delayed gastric emptying. ...
... [25] As the significance of increase in gastric volume by gum chewing is unclear, some studies have suggested restricting it in the immediate preoperative period. [3] In view of the conflicting reports regarding gum chewing in the preoperative period, further studies may be required to determine the exact relationship between gum chewing and pulmonary aspiration. ...
Preoperative fasting period is the prescribed time prior to any procedure done either under general anaesthesia, regional anaesthesia or sedation, when oral intake of liquids or solids are not allowed. This mandatory fasting is a safety precaution that helps to protect from pulmonary aspiration of gastric contents which may occur any time during anaesthesia. We searched PUBMED for English language articles using keywords including child, paediatric, anaesthesia, fasting, preoperative, gastric emptying. We also hand searched references from relevant review articles and major society guidelines. Association of Paediatric Anaesthesiologists of Great Britain and Ireland (APAGBI), the French Language Society of Paediatric Anaesthesiologists and the European Society of Paediatric Anesthetists recommends clear fluid intake upto one hour prior to elective surgery unless specific contraindications exists. Current guidelines recommend fasting duration of 4 hours for breastmilk, 6 hours for milk and light meals and 8 hours for fatty meals. The European Society for Clinical Nutrition and Metabolism (ESPEN) guidelines recommend that oral intake can be initiated within hours of surgery in most patients. While fluids can be started almost immediately, the introduction of solids should be done more cautiously.
... Desde hace varios años se conoce que el ayuno preoperatorio prolongado puede ser perjudicial, ya que induce estrés metabólico y afecta la función mitocondrial y la sensibilidad a la insulina 31 .Desde el 2006 el grupo europeo ERAS (EchancedRecovery After Surgery), enfatiza en la abreviación del ayuno 32 . La reducción de los períodos estándar de ayuno tiene poco o ningún efecto sobre el volumen o el pH del contenido gástrico 33,34 . Un ayuno de 2 horas para líquidos claros es suficiente para asegurar un estómago vacío en la mayoría de los pacientes quirúrgicos elegidos adecuadamente, mientras que no debe consumirse ningún alimento sólido 6 horas antes de la inducción anestésica 3536 La resistencia insulínica (RI) iniciada en el ayuno preoperatorio prolongado aumenta con el trauma quirúrgico y es directamente proporcional a la magnitud de la cirugía. ...
Los pacientes quirúrgicos a menudo tienen un alto riesgo nutricional y esto se asocia con resultados posoperatorios deficientes, poniendo la supervivencia en riesgo.La identificación precoz de este tipo de pacientes es esencial para las intervenciones nutricionales tempranas con el objetivo de atenuar el catabolismo y preservar los procesos de respuesta al estrés quirúrgico que promueven la recuperación e inmunoprotección, reducen la morbimortalidad perioperatoria y mejoran los resultados quirúrgicos.En los últimos años, se han estudiado diversas estrategias nutricionales durante el período perioperatorio que han mostrado beneficios.El objetivo de la presente revisión es analizar la evidencia más reciente sobre la terapia nutricional en pacientes quirúrgicos no críticos; para ello se han consultado bases de datos electrónicas como PubMed, y revistas de las principales sociedades científicas competentes en la materia.
... 21 Preoperative drinking of 400 mL of carbohydrate-containing beverages can reportedly reduce insulin resistance. 22 In accordance with published reports, [23][24][25] we recommend that patients drink a full glass (200 mL) of clear fluid. Therefore, in this study, we used 200 mL as the cutoff when examining the volume of clear fluids consumed. ...
Objectives:
Our aims were to clarify the actual situation regarding preoperative fasting and determine whether multidisciplinary interventions in a perioperative management center shorten the duration of preoperative fasting.
Methods:
The cohort of this before-and-after study comprised patients undergoing elective surgery aged 18 years or older who underwent general anesthesia at one of three stages: after starting a short preoperative fasting protocol (Group A), after the anesthesiologist started explaining the protocol (Group B), and after the start of the perioperative management center (Group C). Instructions on drinking clear fluids were given up to 2 h and 4 h before the start of elective surgery to the first patient on the list (on-time) and to the second and subsequent patients (on-call), respectively. Data were collected retrospectively in Groups A and B and prospectively in Group C.
Results:
The study cohort comprised 89 patients in Group A (50 on-time, 39 on-call), 108 in Group B (65 on-time, 43 on-call), and 284 in Group C (182 on-time, 102 on-call). The difference between the instructed and last drinking time was significantly shorter in Group C than Group A (30 [10, 140] vs. 30 [10, 60] vs. 20 [0, 50] min, p=0.003). The duration of fasting was significantly shorter in Group C than Group B (243 [150, 395] vs. 213 [151, 323] vs. 180 [146, 280] min, p=0.01).
Conclusions:
Multidisciplinary interventions at the perioperative management center tended to reduce the duration of fasting, suggesting that this approach may contribute to improved compliance.
... [3] In view of this, various anesthesia societies have given guidelines, which advocate clear fluids up to 2 h prior to surgery to avoid preoperative patients being starved for longer periods of time. [4][5][6][7] There is literature evidence to demonstrate that the risk of aspiration following liberalized fasting is similar to strict nil per oral (NPO) from midnight. [8] In our institute, patients are evaluated in the Pre-anaesthesia Clinic (PAC) up to 1 week prior to the surgery date. ...
Background and Aims: The preoperative fasting orders given by the Anesthesiologists as per ASA and Enhanced Recovery After Surgery protocol, are often modified by the surgeons, for practical convenience, which can end up with patients being starved for prolonged periods of time. Hence, this study was conducted among various specialty surgical colleagues, to evaluate the knowledge and their perspective regarding patients' preoperative fasting guidelines.
Material and Methods: A validated questionnaire was distributed to 68 surgeons belonging to various surgical specialties, which included consultants and postgraduate residents. The surgeons were grouped as surgeons operating only on children, only on adults, and on adults and children (mixed). Data were summarized using the mean (SD)/median for continuous variables and categorical data were expressed as frequency and percentage. The difference in knowledge score, among the surgeons of three groups, was analyzed using ANOVA, with Bonferroni as post hoc.
Results: This study shows an overall decrease in knowledge (score of 6.13 ± 1.74) about preoperative fasting guidelines among surgeons. We found that the level of knowledge about preoperative fasting guidelines and complications was higher among surgeons who operate only on children (score of 7.05) as compared to surgeons operating only on adults (score 5.5) and adults and children (mixed) (score 6.1), which was statistically significant (P = 0.013). We found no difference in knowledge level based on designation and gender. All the surgeons uniformly had the perspective that patients have to be kept fasting preoperatively.
Conclusion: Preoperative fasting orders for all surgical patients, especially for vulnerable patients such as children and geriatrics, should be administered by the anesthesiologist or surgeon who is familiar with fasting guidelines. We intend to raise the awareness of fasting guidelines of surgical colleagues by putting up placards and posters in the wards.
... Societies of anesthesiologists have developed guidelines that the preoperative fasting protocol should have minimum fasting period of 2 h for clear fluids, 4 h for breast milk, 6 h for infant formula, nonhuman milk, and solid foods (2:4:6). Foods that contain fatty (meat) or fried foods require eight or more additional fasting hours [1][2][3][4]. ...
Background
Fasting before anesthesia is mandatory in children to reduce the complications of regurgitation, vomiting, and aspiration during anesthesia and surgery. Prolonged fasting times have several negative implications in children, because high fluid turnover quickly leads to dehydration, hypotension, metabolic disturbances, and hypoglycemia, resulting in poor anesthetic outcomes.
Aims
This study aimed to assess adherence to preoperative fasting guidelines and associated factors among pediatric patients undergoing elective surgery in Addis Ababa public hospitals in Ethiopia in 2020.
Methods
A cross-sectional survey was conducted in Addis Ababa, which selected public hospitals in Ethiopia, in 2020. A total of 279 pediatric patients aged <17 years scheduled for elective surgery were included in the study. Data analysis was performed using SPSS V.21, and the values of the variables and factors were checked for associations using logistic regression. Statistical significance was determined at P -value of <0.05. The results are presented in text, tables, charts, and graphs.
Results
A total of 279 pediatric patients responded to the analysis, with a 98.6% response rate. The majority of the participants (n = 251, 89.96%) did not follow the guidelines for preoperative fasting. The mean fasting time for clear liquids was 10 ± 4.03 (2–18 h) for breast milk 7.18 ± 2.26 (3.5–12 h), and for solid foods 13.5 ± 2.76 (8–19 h). The reasons for which the preoperative fasting delay was due to incorrect order were 35.1%, prior case procedures took longer times 34.1%, and changing sequence of schedule was 20.8%.
Conclusion
Most children had prolonged fasting. The staff's instructions and schedules were challenged to follow international fasting guidelines.
... American Society of Anesthesiologists defined preoperative fasting as a prescribed period before a procedure when patients are not allowed the oral intake of fluid or solids [1][2][3][4]. Children are required to fast before anesthesia to reduce the volume of the stomach content to reduce the risk of regurgitation and aspiration of gastric contents during the procedure [5]. Different guidelines recommend the minimum fasting period of 2 hours for clear liquids and 6 hours for solids [1,3,[6][7][8][9][10][11][12]. ...
Background. Preoperative fasting is important to reduce the risk of pulmonary aspiration during anesthesia. The influence of prolonged fasting time on glucose levels during anesthesia in children remains uncertain. Therefore, this study is aimed at assessing preoperative fasting time and its association with hypoglycemia during anesthesia in pediatric patients undergoing elective procedures at Tikur Anbessa Specialized Hospital, Addis Ababa, Ethiopia. The research hypothesis of the study is as follows: there is a prolonged preoperative fasting time, and it influences the glucose levels during anesthesia among pediatric patients undergoing elective procedures at Tikur Anbessa Specialized Hospital, Addis Ababa, Ethiopia. Methods. Institutional based cross-sectional study was conducted among 258 pediatric patients who had undergone elective procedures in a tertiary care center. A systematic sampling method was used to select study participants. The data were collected through face-to-face interviews and medical record reviews. Binary logistic regression was used to identify associated factors of hypoglycemia during anesthesia among pediatric patients undergoing elective procedures. All explanatory variables with a value of ≤0.25 from the bivariable logistic regression model were fitted into the multivariable logistic regression model to control the possible effect of confounders, and finally, the variables which had an independent association with hypoglycemia were identified based on adjusted odds ratio with 95% confidence interval, and a value less than 0.05 was significant. Results. The mean (standard deviation) fasting hours from breast milk, solid foods, and clear fluids were 7.75 (2.89), 13.25 (3.14), and 12.31 (3.22), respectively. The majority (89.9%, 57.9%, and 100%) of participants had fasted from solid, breast milk, and clear fluids for more than 8, 6, and 4 hours, respectively. More than one-fourth (26.2%) of participants were hypoglycemic immediately after induction. Residence, order of nothing per mouth, source of patient, and duration of fasting from solid foods had a significant association with hypoglycemia during anesthesia in children. Conclusion. Children undergoing elective procedures were exposed to unnecessarily long fasting times which were associated with hypoglycemia during anesthesia.
1. Introduction
American Society of Anesthesiologists defined preoperative fasting as a prescribed period before a procedure when patients are not allowed the oral intake of fluid or solids [1–4]. Children are required to fast before anesthesia to reduce the volume of the stomach content to reduce the risk of regurgitation and aspiration of gastric contents during the procedure [5]. Different guidelines recommend the minimum fasting period of 2 hours for clear liquids and 6 hours for solids [1, 3, 6–12]. The European Society of Anesthesiologists also suggested a more liberal preoperative fasting protocol for clear liquids (one hour before anesthesia) [13]. Despite the progressive development of guidelines, patients continue to undergo unnecessarily prolonged preoperative starvation to mitigate the risk of aspiration [6]. However, children who were denied oral fluids for more than 6 hours preoperatively did not benefit in terms of intraoperative gastric volume and pH as compared with children who were permitted unlimited fluids up to 2 h preoperatively [14].
Prolonged fasting leads to dehydration, biochemical imbalance, and hypoglycemia, especially in children, and has been discouraged in anesthetic and surgical practice [15–17]. Perioperative hypoglycemia would lead to patient morbidity and mortality, and it is a danger in pediatric practice resulting in anesthetic problems including, lethargy, irritability, metabolic acidosis, and seizures [18]. Prolonged fasting times have several negative implications and lead to poor anesthetic outcomes [19, 20]. Normally, there is a rise in the plasma glucose level in response to surgical stress in normal adults, but children do not respond with a hyperglycemic reaction to the same degree [21]. In Ethiopia, most of the patients fasted from food and fluid longer than the time recommended by the international guidelines. In our setup, the inability to measure glucose when deemed necessary due to inconsistent availability of glucometer makes glucose management more difficult during anesthesia. This is further complicated by a lack of data regarding the incidence of hypoglycemia during anesthesia with a tendency to give dextrose without blood glucose level measurement. The absence of clearly adopted national and institutional preoperative fasting protocols and poor implementation of international guidelines due to lack of knowledge and compliance among health care professionals makes it difficult to predict preoperative fasting times in our patients [3]. Therefore, this study was aimed at assessing the duration of preoperative fasting times and its association with hypoglycemia during anesthesia among pediatrics patients. The statistical hypothesis of the study is as follows: normal fasting times among pediatric patients undergoing elective procedures at Tikur Anbessa Specialized Hospital, Addis Ababa, Ethiopia, and long fasting times among pediatric patients undergoing elective procedures at Tikur Anbessa Specialized Hospital, Addis Ababa, Ethiopia.
2. Methods
2.1. Study Setting
The study was conducted at Tikur Anbessa Specialized Hospital which is found in Addis Ababa (the capital city of Ethiopia) in the Lideta subcity. According to the central statistical agency of Ethiopia (CSA), as of 2013, the town of Addis Ababa has a total population of 3,130,673, of which 1,478,890 are men and 1,624,783 women. It is the nation’s largest and highest referral hospital. This hospital sees approximately 370,000–400,000 patients a year, but the exact number is not known. It has 700 beds. The hospital is the largest tertiary care teaching center in the country where many subspecialty services are delivered including pediatric surgery. The hospital is planned and accommodated and facilitated with the outpatient department (OPD), which has seven X-ray, nine surgical, and two diagnostic laboratory rooms; internal medicine, gynecological and obstetrics, surgical, pediatrics, and emergency departments; and referral clinics (chest, renal, neurology, cardiology, dermatology, sexually transmitted diseases, gastrointestinal, infectious diseases, orthopedics, general surgical, gynecologic and obstetrics, diabetic, hematology, and medical intensive care units).
2.2. Study Design and Period
An institution-based cross-sectional study was employed from June to October 2019, at Tikur Anbessa Specialized Hospital (TASH) which is located in Addis Ababa, the capital city of Ethiopia.
2.3. Study Population
All pediatric patients aged less than 14 years old who have been scheduled for elective procedures were the study populations. All pediatric patients aged 0-14 years, who had undergone elective procedures (elective surgery, MRI, gastrointestinal endoscopy, bronchoscopy, bone marrow aspiration, and biopsy), were included. And patients with the known metabolic or endocrine disorders were excluded from the study.
2.4. Sample Size
The required sample size was determined by the single population proportion formula, considering the proportion of hypoglycemia among pediatric patients as computed using the formula with the input 95% confidence level () and 5% margin of error () and estimating a proportion () 50%,. However, the number of pediatric patients who were scheduled for elective procedures and sedation for the past three consecutive months was 600. So we have used a correction formula and the final sample size was 258.
2.5. Sampling Technique
A systematic sampling method was used to select study participants. All unique medical registration numbers of a child who came for elective procedures from June to October 2019 were selected from the elective surgery registration logbook and were sorted based on their unique medical registration number in an ascending order (1, 2, 3, 4, etc.) By using a systematic sampling technique, children’s charts were selected until the required sample size is obtained in every 2nd (where 600/258). The first study subject was the first one when it was selected by lottery method from the first 2 of children. Then, the selected children were contacted on the day of their schedule, and the data collectors extracted the required data from the selected charts and through face-to-face interviews.
2.6. Data Collection Tools and Procedures
Information about study variables was collected by three BSc nurses through face-to-face interviews of the caregivers and review of patient’s medical records using chart extraction form and filled to a structured questionnaire adapted from different works of literature. The questionnaire incorporated sociodemographic data of the patients and the caregivers, clinical data, and questions related to preoperative fasting durations of the patients as reported by the caregivers. A preoperative fasting (NPO) time is the duration between the time patients last took any form of an enteral meal including clear fluids and breast milk and the time of induction. Information about preoperative fasting times was collected through face-to-face interviews with the caregivers. The capillary blood glucose level at the fingertip was measured using a capillary glucometer (ON-Call Extra) immediately after induction of anesthesia (but before the procedure begins), at the end of the procedure, and at a random time for those procedures whose procedure time took more than one hour. Any glucose level less than 54 mg/dl was reported as hypoglycemia [22], and glucose mg/dl was considered as hyperglycemic [23], and we made sure that the first glucose measurement was done before the patient was given any form of IV dextrose. Sociodemographic information like age and sex of patients and caregivers as well as educational status, marital status, and the job of the caretakers was collected through face-to-face interviews with the caregivers. Other clinical variables like type of surgery and American Society of Anesthesiologists (ASA) class were collected through reviewing medical charts of the patients. Children were categorized as ASA class I if they were well built and had no limitation during walking or playing; ASA class II if they had advanced malignancy (example hematologic malignancy) and if they were grossly malnourished or had mild limitation of walking, playing, or other age-appropriate activities; and ASA class III if they had active heart or lung problems, if they were debilitated or bedridden, or if they were premature infants with postconception age less than 60 weeks.
2.7. Data Quality Management
Before collecting our data, the data extraction checklist was prepared in English and pretested to gather relevant data from the medical records. To ascertain the data quality, data collection was conducted by three BSc nurses. The training was given to the data collectors on how to fill the questionnaire, clarification of the whole study tools, variables, and research ethics. Continuous monitoring and supervision were done by the principal investigator every day for completeness and clarification of the data. Pretest was conducted on 5% of the sample size at TASH, and necessary corrections and modifications were done on the study tool.
2.8. Data Processing and Analysis
Data clean-up and cross-checking were done before analysis. Data was checked; recoded and completed questionnaires were given identification numbers and entered to SPSS version 25 for analysis. Binary logistic regression was used to identify associated factors of hypoglycemia just after induction among pediatric patients undergoing elective procedures at Tikur Anbessa Specialized Hospital. Variables with a value of ≤0.25 from the bivariable logistic regression model were fitted into the multivariable logistic regression model to control the possible effect of confounders, and finally, the variables which had an independent association with were identified based on AOR with 95% CI, and a value less than 0.05 was significant. Data were entered, cleaned, and coded into SPSS, V25 software, and for analysis. Simple descriptive statistics such as frequency mean and standard deviations were calculated. Then, to see the relationship of independent variables with the dependent variable, binary logistic regression was performed, and to see the effect of each independent variable on the dependent variable, multivariable logistic regression was calculated. As a result, crude and adjusted odds ratio with a 95% confidence interval was calculated. A value of less than or equal to 0.05 was considered significant.
3. Result
3.1. Sociodemographic Characteristics of Study Participants
There were 258 eligible respondents, and none of them refused to participate giving a response rate of 100%. The mean age of participants was () of which 43% are within the group of 5-14 years and the majority 171 (66.3%) of them were male. Most of the caregivers (69) (26.7%) had completed primary education, and 45 (17.4%) were unable to read and write; eighty-eight (34.1%) of the caregivers were merchants while 45 (17.4%) were housewives/jobless. Most of the caregivers (246) (95.3%) were married. Similarly, a considerable proportion of 184 (71.3%) came for the service outside of Addis Ababa (Table 1).
Variables
Category
Frequency ()
Percent (%)
Age of the patients in years
<1
48
18.6
1-4
99
38.4
5-14
111
43.0
Sex of the patient
Male
171
66.3
Female
87
33.7
Relation of the caregivers to the patient
Mother
162
62.8
Father
93
36.0
Brother
3
1.2
Age of the caregivers in years
<35
142
55
36-50
98
38
51-65
18
7
Educational status of the caregivers
Unable to read and write
45
17.4
Able to read and write
38
14.7
Primary education
69
26.7
Secondary education
64
24.8
College and above
42
16.3
Occupation
Housewife/jobless
75
29.1
Government employee
37
14.3
Nongovernment employee
34
13.2
Farmer
24
9.3
Merchant
88
34.1
Marital status of the caregivers
Married
232
89.9
Single
12
4.7
Divorced
14
5.4
Residence
Addis Ababa
74
28.7
Outside of Addis Ababa
184
71.3
... 6,8 On the other hand, recent guidelines from worldwide multiple anesthesiology societies suggest that overnight fasting should be approached with flexible durations and proper techniques. 9,10 Many complications can result from prolonged fasting and preoperative starvation as the duration of fasting usually lasts for more than 12 hours secondary to intraoperative surgical delays. 11 Among the reported effects, insulin resistance exaggerated immune response and acute phase reactions have been reported to induce serious damage to the body and multiple organs ( Figure 1). ...
Although recent reports discourage preoperative overnight fasting, many clinicians and surgeons still recommend 6-8 hours of overnight preoperative fasting before conducting elective surgeries. On the other hand, recent guidelines from worldwide multiple anesthesiology societies have suggested that overnight fasting should be approached with flexible durations and proper techniques. Many complications can result from prolonged fasting and preoperative starvation as the duration of fasting usually lasts for more than 12 hours secondary to intraoperative surgical delays. In this literature review, the aim was to discuss the current evidence from studies in the literature about the effect of preoperative starvation and the effect of carbohydrate (CHO) loading on the clinical outcomes of patients. We have noticed that gastric aspiration and respiratory damage can be prevented by preoperative fasting. However, this can lead to the development of other complications such as insulin resistance, a fierce immune response and exaggerated release of acute-phase reactants which might lead to severe organ damage and worsened patient’s prognosis. Accordingly, CHO loading should be carefully approached to properly intervene against these cases to enhance the prognosis of the prospective surgeries and the quality of care for patients.
... 1 The relevant societies in the United States and most European countries have led such approaches to adjust the preoperative fasting guidelines and suggested that clear fluids can be orally allowed until 2-3 hours preoperatively except when a procedure for evaluating gastric emptying was planned. 3 In general, strategies following restrictive fluid management approaches are encouraged during certain procedures as those involving patients with severe respiratory distress undergoing major surgical operations as they are thought to decrease the time spent on mechanical ventilation and frequency of any potential cardiopulmonary complications. 4,5 Malbrain et al. 6 conducted a meta-analysis to study the effect of frequency of fluid overhydration and resuscitation of critically ill patients. ...
This literature review aims to highlight the possible causes, complications, and management of this event from previously published studies discussing dehydration in critically-ill patients admitted to the emergency room (ER). In general, the administration of fluids has been used in the ER for critically-ill patients for many purposes. These include the optimization and adjustment of body fluids and electrolytes, increase renal protection against contrast, enhance uric acid, globins, caloric intake, and as an adjuvant to ameliorate the potentiality of certain medications or to dilute them. Many etiologies have been accused to cause dehydration in critically-ill patients. These include the fasting strategy that patients are obliged to whenever undergoing a surgical operation. Kidney, heart, and liver injuries have also been associated with patients’ dehydration. Old age and the presence of other co-morbidities diabetes insipidus and uncontrolled diabetes can also aggravate the condition. Mental affection is the main complication that patients with severe dehydration might complain about. Other complications might include aggravation of heart failure, and skin diseases, and deterioration of the kidney functions and other cellular processes that require adequate nourishment for their daily normal functions. Mortality is also a serious common complication, especially within elderly patients. Although the management of dehydration can be easily achieved by fluid administration, fluid overload can aggravate the underlying complications and develop others. Therefore, the main challenge here would be to frequently monitor patients during fluid administration and resuscitation to prevent this side effect.
... This points to likely differences in how each meal and the lipid phases, specifically, emptied from the stomach. Gastric emptying rate is influenced by meal composition and structure, with water and clear fluids generally emptying faster than solid fractions (55,56). In the case of an acid-unstable lipid emulsion, the aqueous phase empties faster than the destabilized upper lipid layer (28). ...
Background:
The influence of triacylglycerol (TAG) physical properties on satiety remains poorly understood.
Objectives:
The objective was to investigate if and how TAG digestion and absorption, modulated only by differences in TAG crystallinity, would differentially affect short-term satiety in healthy men.
Methods:
We tempered 500 mL 10% palm stearin oil-in-water emulsions such that the lipid droplets were either undercooled liquid (LE) or partially crystalline solid (SE). Fifteen healthy men (mean ± SD age: 27.5 ± 5.7 y; BMI: 24.1 ± 2.5 kg/m2; fasting TAG: 0.9 ± 0.3 mmol/L) consumed each beverage at two 6-h study visits separated by ≥6 d after an overnight fast, along with 1500 mg acetaminophen suspended in water. The participants characterized the emulsion sensory properties, completed satiety visual analog scale ratings, and had serial blood samples collected for 6-h analysis of plasma peptide YY (PYY), glucagon-like peptide-1 (GLP-1), ghrelin, leptin, glucose-dependent insulinotropic polypeptide (GIP), insulin, and acetaminophen (for assessing gastric emptying). Repeated-measures ANOVAs and 2-tailed paired t tests were used to analyze the changes from baseline and incremental area under the curve (iAUC) values, respectively.
Results:
With consumption of LE compared with SE, there was a 358% higher fullness (P = 0.015) and a 103% lower average appetite (P = 0.041) score, along with higher iAUC values for PYY (P = 0.011) and GLP-1 (P = 0.028) (103% and 66% higher, respectively), but not for ghrelin (P = 0.39), based on change from baseline values. Acetaminophen response trended toward significance (P = 0.08) and was 15% higher with LE. SE was rated as 44% thicker (P = 0.034) and 24% creamier (P = 0.05) than LE.
Conclusions:
The suppression of TAG digestion by the presence of partially crystalline lipid droplets blunted the appetite-suppressing effects of an oil-in-water emulsion.This trial was registered at clinicaltrials.gov as NCT03990246.
... There has been no increased incidence of adverse events. 25 There is no evidence to suggest that increasing fasting times in high-risk patients reduces aspiration risk, and current guidelines are standardised across all patients. However, in children the contraindications listed by the adopted consensus statement include: gastro-oesophageal reflux (either being treated or investigated), renal failure, some enteropathies, oesophageal strictures, achalasia, diabetes mellitus with gastroparesis, or surgical contraindications. ...
... The feelings of thirst, hunger, mouth dryness, nausea, vomit, and weakness were assessed using VAS scores 0 to 10 before anesthesia induction, after extubation, and after sending back to ward. [19] Score 0 means patients have no discomfort at all and score 10 presents patients have the most severe discomfort. Higher score means more severe discomfort. ...
Background:
Preoperative oral carbohydrate (POC) has been recommended as an important element of the enhanced recovery after surgery (ERAS) protocol, but its effect on patients undergoing endoscopic submucosal dissection (ESD) remains unclear. Our study aims to investigate the effects of POC for ESD surgery, with particular focus on perioperative well-being and gastric peristalsis.
Methods:
A prospective, randomized, and controlled study of patients undergoing ESD was conducted. Seventy-three patients were assigned to 2 groups: experiment (36 patients) and control (37 patients). The experiment group received oral carbohydrate solution 710 mL the night before and 355 mL 2 hours prior to operation. The control group fasted for 10 hours prior to operation. Gastric empty assessment, peristaltic score, and operation score were measured. In addition, visual analogue scale (VAS) scores for 6 parameters (thirst, hunger, mouth dryness, nausea, vomit, and weakness) of wellbeing were compared perioperatively. Preoperative basic conditions of patients, postoperative complications, and their clinical outcomes were also recorded.
Results:
Before anesthesia induction, gastric sonography score was higher in experiment group, while sucked fluid by gastroscopy was similar between 2 groups. And no patient had regurgitation. Moreover, gastric peristaltic score and operation score before operation were both lower in experiment group. Importantly, VAS scores for 3 parameters (thirst, hunger, and mouth dryness) were significantly lower in experiment patients. In addition, clinical outcomes including first time exhaust, first time for drinking water, the usage of hemostasis, postoperative complication, lengths of hospital stay, and in-hospital expense were not significantly different between 2 groups.
Conclusions:
Oral administration of carbohydrates preoperatively instead of fasting improves the feelings of thirst, hunger, and mouth dryness in patients following ESD surgery without enhancing risk of regurgitation. And, avoiding preoperative fasting with POC can decrease the degree of gastric peristalsis that may facilitate the successful completion of ESD surgery.
... Given the 10-30 minute half-time to empty clear fluids, 95% of the gastric fluid volume should empty the stomach within 40-120 minutes, which clearly exceeds the 1 hour fasting interval in some cases, particularly if the fluid contains sugars or other dissolved constituents. 2 Interestingly, the gastric fluid volume purportedly after 1 and 2 hours in one study 3 actually included no children who fasted for the designated interval; they fasted about 25% longer than assigned. 4 In a review of fasting guidelines in children, the authors asserted that the relationship between the fasting interval after clear fluids and residual gastric fluid volume is weak, 3 although a graphical display of the fasting data cited fit a very tight exponential decay curve (( Figure, r 2 =0.90). ...
I read with interest recent the APA‐ESPA‐ADARPEF joint consensus statement and the SPANZA endorsement to reduce the fasting interval after clear fluids in children to 1 hour. I am fully committed to re‐examining fasting guidelines in children periodically. However, abbreviating the fasting interval to the point where flexibility to change the order of the surgical list in the face of an unexpected delay or cancellation occur is eliminated, would preclude our ability to run an efficient operating room schedule.
This article is protected by copyright. All rights reserved.
... Mortality from regurgitation and aspiration of gastric contents under anaesthesia, had since been documented [1] with several developments eventually leading to the prescription of pre-operative fasting guidelines [2][3]. Despite a fairly good knowledge of these fasting guidelines by medical practitioners, the preoperative fasting period is frequently extended far beyond the limits owing to the overnight fast that precedes a normal scheduled operation list, busy theatre sessions and logistic constraints, with concerns about the likely development of hypoglycaemia, especially in children in whom scanty glycogen store is often cited. ...
Background: The fatal risk of pulmonary aspiration of gastric contents during anaesthesia had since been recognized and consequently preoperative fasting guideline is usually prescribed to prevent this. Concern about development of hypoglycaemia during prolonged fasting has often been expressed, especially in children. AIM: This study is intended to determine the fasting blood glucose in preoperative patients of different age groups who were fasted for varying duration of time, and determine whether indeed hypoglycaemia occurs during inadvertently prolonged fasting which we often encounter in our practice setting. Methodology: A prospective cohort study of fasting blood glucose (FBG) of patients presenting for elective surgery in the principal investigator’s operating rooms at the National Orthopaedic Hospital, Enugu, Nigeria was carried out. Blood glucose meter was used for estimation of glucose in capillary whole blood of the patients and the obtained data were analysed using SPSS version 16.0 statistical software. Comparison of mean values was done using the Chi-square test with statistical significance put at P < 0.05. Results: Out of one hundred and thirty three patients studied with mean age of 30.2 ± 19.60 years (range: 1-72 years), and mean duration of fasting 12.73 ± 2.01 hours, (range: 8-16 hours), the mean fasting blood glucose was found to be 91.49 ± 13.36mg/dl (range: 58 - 124mg/dl). No relationship was found between age and FBG (Pearson’s correlation coefficient, r = 0.025). Likewise duration of fasting did not relate with FBG (Pearson’s correlation coefficient, r = 0.088). One patient (0.8%) had hypoglycaemia, with blood glucose of 58mg/dl. Conclusion: Hypoglycaemia as a consequence of pre-operative fasting is rare, even in non-infants fasted for considerably long hours. Neither patient’s age, gender, nor duration of fasting had any significant influence on the fasting blood glucose of the patients.Keywords: Hypoglycaemia; pre-operative fasting; whole blood; Plasma.
... In a study by Bisinoti et al., the stomach was determined not to be empty by gastric measurements of 26.4% of patients [29]. It has been suggested that there could be patient incompatibility or known or unknown gastric motility impairment because of increased gastric content in elective patients [30]. ...
Background
Pulmonary aspiration of the gastric contents is a serious perioperative complication. The aim of this study was to evaluate the efficacy of portable ultrasonography in the preoperative evaluation of the gastric contents of patients. The secondary aim was to examine the relationship between gastric antrum cross-sectional area and age and body mass index (BMI).
Material/Methods
This single-center, prospective, cross-sectional study included 120 patients who underwent surgery. Measurements the gastric antral cross-sectional areas and quantitative and qualitative measurements of the stomach were taken by ultrasonography guidance in all patients.
Results
With the patient in a supine position, the mean gastric antrum cross-sectional area was found to be 3.4±2.43 cm² (range, 0.79–17.3 cm²). As the number of hours of fasting increased, the gastric antral cross-sectional area statistically significantly decreased (P<0.05). Increased age and BMI values were determined to increase the gastric antrum cross-sectional area in a linear correlation; r=0.209, P<0.05 and r=0.252, P=0.05, respectively. It was determined that 20.8% of the patients exceeded the high-risk stomach antral cutoff cross-sectional area that was defined as 340 mm² in patients fasting for at least 8 hours.
Conclusions
It was determined that bedside ultrasonography is a useful, non-invasive tool in the determination of gastric content and volume. A significant proportion of surgical patients may not present with an empty stomach despite the recommended fasting protocols.
This review discusses the evolution of preoperative fasting guidelines and examines the incidence of pulmonary aspiration of gastric contents and suggested treatments.
Nine guidelines developed by professional societies and published in peer-reviewed journals since 1994 were identified. The recommendations on preoperative fasting for various categories have undergone only small adaptations in the following three decades in pediatric anesthesia.
We found twelve published studies of the incidence of pulmonary aspiration, which ranges from 0.6 to 12 in 10,000 anesthetics in children. However, this variation reflects differences in the definition of aspiration as well as differences in study design. The main risk factors identified are emergency surgery, ASA physical status, and patient age. Several additional risk factors have been suggested, including non-compliance to fasting guidelines.
The duration of clear fluid fasting is not associated with an increased risk of pulmonary aspiration and may be reflected in future guideline updates in pediatric anesthesia.
Background
Preoperative fasting for six hours and accepting clear fluids till two hours of surgery is followed as a regular practice. Carbohydrate-rich fluids antagonize catabolism and are claimed to be tolerated better. This study aims to compare the effect of carbohydrate-rich drinks on gastric volume and blood sugar control in diabetic and non-diabetic patients undergoing elective surgery with plain water.
Methods
Two hundred forty patients aged 40 to 65 undergoing elective surgery under regional anesthesia were randomized into diabetic control, diabetic study, non-diabetic control, and non-diabetic study. Control groups were given 400 ml of plain water, while the study group received 50 grams of dextrose dissolved in 400 ml of water two hours prior to surgery. Gastric volume was evaluated using USG, and thirst and discomfort were assessed using the Likert scale. Perioperatively, blood sugar values were monitored and kept under control using insulin.
Results
Mean gastric volume (ml) in diabetic control (35.3±12.95 ml), diabetic study (31.2±11.75 ml), non-diabetic control (29±11.42 ml), and non-diabetic study (30.4±9.12 ml) showed no statistically significant difference (p>0.05). Capillary blood glucose (CBG) values two hours post fluid intake showed a significant increase in CBG levels in the diabetic study (183.2±28.67 mg/dl) compared to the diabetic control group (138.66±15.81 mg/dl). The values returned to baseline within six hours. Thirst and discomfort were significantly lower in the study group of diabetic and non-diabetic populations.
Conclusion
We conclude that carbohydrate loading does not affect gastric volume in diabetics and non-diabetics. However, the sugar values do increase which may warrant hourly checking and administration of insulin in diabetics.
Background:
Critically ill patients frequently accrue substantial nutritional deficits due to multiple episodes of prolonged fasting prior to procedures. Existing literature suggests that for most patients receiving tube feeding the aspiration risk is low. Yet, national and international guidelines do not address fasting times for tube feeding, promoting uncertainty regarding optimal pre-procedural fasting practice. We aimed to characterize current institutional fasting practices in the United States for patients with and without a secure airway, with variable types of enteral access, for representative surgical procedures.
Methods:
The survey was distributed to a purposive sample of academic institutions in the United States. Reponses were reported as restrictive (six to eight hours pre-procedurally) or permissive (less than six hours or continued intra-procedurally) feeding policies. Differences between level 1 trauma centers and others, and between burn centers and others, were evaluated.
Results:
The response rate was 40.3% (56 of 139 institutions). Responses revealed a wide variability with respect to current practices, with more permissive policies reported in patients with secure airways. In patients with a secure airway, Level 1 trauma centers were significantly more likely to have permissive fasting policies for patients undergoing an extremity incision & drainage for each type of feeding tube surveyed.
Conclusions:
Current hospital policies for pre-procedural fasting in patients receiving tube feeds are conflicting and are frequently more permissive than guidelines for healthy patients receiving oral nutrition. Prospective research is needed to establish the safety and clinical effects of various fasting practices in tube-fed patients. This article is protected by copyright. All rights reserved.
Background
Diabetes mellitus may increase the risk of adverse perioperative outcomes and prolong hospital stay. An enhanced recovery program (ERP) reduces surgical stress and its metabolic consequences, so attenuating the impact of preoperative risk factors. We tested the hypothesis that diabetes would have only a minor impact on outcome after colorectal surgery with an ERP.
Methods
The data for patients scheduled for colorectal surgery between 2015 and 2021, were analyzed (n = 769). All the patients were managed with the same protocol. Demographic data, preoperative risk factors, postoperative complications, and length of stay were compared between patients with and without diabetes.
Results
In all, 124 patients (16.1%) had diabetes, of whom 30 (24.1%) required insulin. The following preoperative risk factors for postoperative complications were significantly more frequent in the patients with diabetes: age > 70 years, ASA score ≥ III, renal failure, cardiac disease, BMI > 30 kg/m², anemia, and cancer as indication for surgery. Despite more risk factors, patients with diabetes did not experience more overall postoperative complications than controls (OR (95%IC): 0.9 [0.6–1.5], p = 0.85). Length of hospital stay was not significantly longer in patients with diabetes than in those without (4 [2–7] vs. 3 [2–7] days; p = 0.45).
Conclusions
Despite more risk factors, patients with diabetes did not experience more complications or longer length of stay after colorectal surgery with an ERP. The multimodal, multidisciplinary approach of ERP to reducing surgical stress may thus help mitigate the reported deleterious effects of diabetes.
Résumé
Contexte
Le diabète sucré peut augmenter le risque de complications périopératoires et prolonger le séjour à l’hôpital. Un programme de réhabilitation améliorée après chirurgie (RAC) réduit le stress chirurgical et ses conséquences métaboliques, atténuant ainsi l’impact des facteurs de risque préopératoires. Nous avons testé l’hypothèse selon laquelle le diabète n’aurait qu’un impact mineur sur les suites opératoires après une chirurgie colorectale lors d’un programme de RAC.
Méthodes
Les données des patients programmés pour une chirurgie colorectale entre 2015 et 2021 ont été analysées (n = 769). Tous les patients ont été pris en charge avec le même protocole de RAC. Les données démographiques, les facteurs de risque préopératoires, les complications postopératoires et la durée du séjour ont été comparés entre les patients avec et sans diabète.
Résultats
Au total, 124 patients (16,1 %) étaient diabétiques, dont 30 (24,1 %) étaient traités par insuline. Les facteurs de risque préopératoires suivants pour les complications postopératoires étaient significativement plus fréquents chez les patients diabétiques : âge > 70 ans, score ASA ≥ III, insuffisance rénale, cardiopathie, IMC > 30 kg/m², anémie et cancer comme indication de la chirurgie. Malgré un plus grand nombre de facteurs de risque, les patients diabétiques n’ont pas souffert de plus de complications postopératoires globales que les patients non diabétiques (OR [IC95 %] : 0,9 [0,6–1,5], p = 0,85). La durée de l’hospitalisation n’était pas significativement plus longue chez les patients diabétiques que chez les autres (4 [2–7] jours contre 3 [2–7] ; p = 0,45).
Conclusions
Malgré un plus grand nombre de facteurs de risque, les patients diabétiques ne présentaient pas plus de complications ni une durée de séjour plus longue après une chirurgie colorectale lors d’un programme de RAC. L’approche multimodale et multidisciplinaire de la RAC pour réduire le stress chirurgical pourrait donc contribuer à atténuer les effets délétères du diabète.
Purpose
This study aimed to investigate the effect of preoperative oral carbohydrates (POC) on patients undergoing gynecological laparoscopic surgery with different fasting times.
Design
A randomized control study.
Methods
Two hundred patients were randomly divided into F group (first operation without carbohydrates intake), S group (second operation without carbohydrates intake), Fpo group (first operation with POC intake), and Spo group (second operation with POC intake). The visual analog scale (VAS) of thirst and hunger, perioperative buffer excess (BE), electrolyte and glucose levels, as well as insulin resistance (IR) were compared. Time to first flatus, hospital stay, and eating time were also recorded.
Findings
POC reduces the aggravation of thirst and hunger discomfort during the perioperative period. Abnormal perioperative BE and lactate levels were found in patients of F and S groups, while those in the Fpo and Spo groups almost returned to normal. Patients in all groups had preoperative hypokalemia, and those in the Fpo and Spo groups recovered quickly to normal intraoperatively. IR in patients in the Fpo and Spo groups retured to preoperative levels after surgery while, those in the F and S groups persisted until 48 hour postoperatively. No significant differences in postoperative nausea and vomiting, time to first flatus, time of first eating, and postoperative hospital stay were found among the four groups.
Conclusion
POC accelerates postoperative recovery in patients undergoing gynecological laparoscopy with different fasting times.
Simple Summary
Gastro-oesophageal reflux (GOR) is an anaesthetic complication that causes oesophageal inflammation and stricture in animals. The aim of this systematic review is to systematically identify the effect of preoperative fasting duration and drugs (anaesthetic and nonanaesthetic agents) on GOR in dogs and cats during anaesthesia. Seven studies were included in the meta-analysis. Many factors seem to affect the development of GOR in dogs and cats. However, there is a limited number of studies investigating these factors, and as the level of evidence is low-to-medium, no reliable conclusions can be extracted.
Abstract
In animals, gastro-oesophageal reflux (GOR) may occur during anaesthesia, and it can lead to severe consequences such as oesophagitis and oesophageal stricture. This systematic review investigates the effect of fasting duration and anaesthetic and nonanaesthetic drugs on GOR in dogs and cats during general anaesthesia. Fifteen clinical studies met the inclusion criteria in this systematic review. In thirteen studies the population was dogs, while in two studies the population was cats. In the meta-analysis, seven studies were included. Four studies on the effect of fasting duration on GOR in dogs were included in the meta-analysis. In total, 191 dogs had a fasting duration less than 5 h, while 311 dogs had a fasting duration more than 5 h. The heterogeneity of the studies was high and statistically significant (p = 0.0002, I² = 85%), but the overall effect was statistically nonsignificant (p = 0.82, odds ratio = 0.81, 95% CI 0.15, 4.26), in favour of the low fasting duration (<5 h). Concerning the effect of antacids on GOR, three studies were included in the meta-analysis. The heterogeneity of the studies was low and nonsignificant (p = 0.13, I² = 52%) and the overall effect was statistically nonsignificant (p = 0.24). The low number of studies and the diverse factors affecting the incidence of reflux prevented us from reaching valuable conclusions on the risk factors for GOR.
This study aimed to investigate the effect of three different preoperative fasting regimens on the incidence of gastro-oesophageal reflux (GOR) in dogs under general anaesthesia. Ninety dogs undergoing non-abdominal and non-thoracic elective surgery were included in the study and equally allocated to three groups. Dogs received canned food providing half the daily resting energy requirements (RER) 3 h prior to premedication (group 3H), a quarter of the daily RER 3 h before premedication (group 3Q), and half the daily RER 12 h before premedication (group 12H). The animals were premedicated with acepromazine and pethidine, anaesthesia was induced with propofol and maintained with isoflurane vaporised in oxygen. Oesophageal pH was monitored throughout anaesthesia. Demographic and surgery-related parameters were not different among groups. The incidence of GOR was 11/30 in group 3H (36.7%), 9/30 in group 3Q (30.0%) and 5/30 in group 12H (16.7%), which was not statistically different (p = 0.262). Reduction of the amount of the preoperative meal from half to a quarter of the daily RER did not reduce the incidence of GOR but resulted in a lower oesophageal pH (p = 0.003). The results of this study suggest that the administration of a meal 3 h before anaesthesia does not have any beneficial effect in the reduction of GOR incidence in dogs compared to the administration of a meal 12 h before anaesthesia.
Objective: This study was conducted to investigate the effect of preoperative fasting period on postoperative agitation, nause and vomiting in children with tonsillectomy. Material and Methods: Children (n:123) who have had tonsillectomy between June and December 2017 and their families have taken place in the study. The data were collected by the researchers with a questionnaire. The data were analyzed using the SPSS 18 package program and with descriptive, Mann Whitney U test, Spearman Correlation test. Results: The mean duration of preoperative fasting was 11.03±1.17 hours, the duration of thirst was 10.17±1.00 hours. The mean behavior scores of the children were 1.28±0.27 points, the mean vomiting score of the children was 0.01±0.07 points, 56.9% of the children in the postoperative unit were not experiencing nausea. Between duration of preoperative fasting with agitation and vomiting status in postoperative unit was found to statistically no relationship. According to preoperative fasting time of children, a statistically significant difference was found when children were diagnosed as having or not having symptoms of nausea. Conclusıon: It was found that the children had longer duration of preoperative fasting than the guidelines suggested in the guidelines. It was observed that pre-operative fasting time did not affect postoperative agitation and vomiting, but it affected nausea. Practice Implications: Surgical nurses should emphasize the importance of fasting period to families before surgery and inform families on this issue.
Résumé
L’échographie antrale permet d’apprécier la vidange gastrique mais également d’analyser l’impact de la durée de jeûne sur le risque de présenter un estomac plein avant une anesthésie générale. Les données récentes issues des études portant sur l’échographie de l’antre gastrique pourraient contribuer, à l’avenir, à une libéralisation des règles de jeûne préopératoire concernant, par exemple, la consommation de liquides clairs, de solutions de carbohydrates, d’une tasse de café ou de thé au lait ou de chewing-gum, chez l’enfant et l’adulte en dehors de la grossesse, mais également chez la femme enceinte à terme en dehors du travail. Ces données pourraient également contribuer à autoriser la consommation d’un petit déjeuner léger jusqu’à quatre heures avant l’induction d’une anesthésie générale pour une chirurgie programmée en dehors du contexte obstétrical. Alors que les études issues de l’échographie gastrique peuvent confirmer le caractère sécuritaire de la consommation de liquides clairs ou de solutions de carbohydrates chez la parturiente, elles semblent décourager la consommation d’aliments solides au cours du travail obstétrical. Des études complémentaires utilisant l’échographie antrale seront nécessaires afin d’évaluer l’impact de la libéralisation des règles de jeûne sur le risque de présenter un estomac plein avant une anesthésie générale, avant l’intégration d’une telle libéralisation dans de futures recommandations.
Major abdominal surgery encompasses a broad range of operations with a wide variety of procedures that fall under this category. The perioperative management after a low-risk procedure such as a herniorrhaphy is going to be different from the management following a high-risk procedure such as a pancreaticoduodenectomy. The majority of patients undergoing major abdominal surgery often present with cancer and other medical comorbidities and are put at an elevated risk of a large number of medical and surgical perioperative complications. There are a significant number of factors that make up the risk profile of patients undergoing major abdominal surgery. This elevated risk results from the problem of a significant surgical stress response in older patients with minimal functional or physiological reserve. In this chapter, we will explore several areas of perioperative management uniquely associated with major abdominal surgery. We will address prevention of pulmonary complications, fluid management strategies, nutrition, and surgical site infections. The prevention and treatment of delirium, deep venous thrombosis, and urinary tract infections are important in the management of patients following major abdominal surgery and are covered in depth in the other chapters in this textbook.
The ACERTO project is a multimodal perioperative care protocol. Implemented in 2005, the project in the last 15 years has disseminated the idea of a modern perioperative care protocol, based on evidence and with interdisciplinary team work. Dozens of published studies, using the protocol, have shown benefits such as reduced hospital stay, postoperative complications and hospital costs. Disseminated in Brazil, the project is supported by the Brazilian College of Surgeons and the Brazilian Society of Parenteral and Enteral Nutrition, among others. This article compiles publications by the authors who belong to the CNPq research group “Acerto em Nutrição e Cirurgia”, refers to the experience of other national authors in various surgical specialties, and finally outlines the evolution of the ACERTO project in the timeline.
Pengelolaan pasien emergensi memiliki tantangan tersendiri bagi anestesiologis. Resiko terjadinya aspirasi isi lambung sangat besar pada pasien emergensi. Angka kejadian aspirasi isi lambung pada pasien emergensi berkisar antara 0,7-4% yang dapat berakibat kematian. Disfungsi gastrointestinal sering terjadi pada pasien dengan cedera otak traumatika. Lebih dari 50% pasien dengan cedera kepala berat tidak mentoleransi enteral feeding. Intoleransi ini manifest dengan adanya muntah, distensi abdominal, pelambatan pengosongan lambung, refluks oesofageal dan penurunan peristaltik intestinal, yang menunjukkan bahwa disfungsi gastrointestinal adalah fenomena yang umum setelah cedera otak traumatika. Puasa merupakan pencegahan yang efektif untuk mengurangi terjadinya resiko aspirasi isi lambung, namun pada kasus emergensi sulit untuk dilaksanakan. Berbagai upaya yang dapat dilakukan pada pasien emergensi untuk mengurangi angka kejadian aspirasi adalah: a) pemberian obat-obatan tertentu sebelum dilakukannya anestesi: histamine 2-reseptor antagonis (ranitidine, cimetidine), proton pump inhibitor (omeprazole), antacid (sodium citrate, magnesium trisilicate) dan antiemetic (ondansentrone), b) posisi kepala yang lebih tinggi dari tubuh 30-45o, c) rapid sequence induction dengan sellick maneuver, d) pemasangan pipa naso atau orogastric dan aspirasi isi lambung. Rapid sequence induction tidak memberi kesempatan untuk mencegah kenaikan tekanan darah saat laringoskopi dan intubasi, padahal untuk pasien dengan kelainan serebral termasuk cedera otak traumatika, harus dihindari lonjakan tekanan darah yang akan meningkatkan tekanan intrakranial. Aspirasi isi lambung merupakan komplikasi anestesi yang mungkin terjadi pada periode perioperatif khususnya pada pasien emergensi. Pengelolaan yang adekuat mampu untuk mengurangi terjadinya resiko aspirasi.
Strategy to Prevent Gastric Content Aspiration in Emergency Traumatic Brain Injury Surgery
Management of an emergency patients has a particular challenge for an anesthesiologist. The risk of pulmonary aspiration from gastric content is very high in emergency cases. The incidence of gastric aspiration in emergency cases is approximately 0.7-4% which could lead to death. Gastrointestinal dysfunction frequently occurs in patients with traumatic brain injury (TBI). More than 50% patients with severe head injuries could not tolerate enteral feedings. This intolerance is manifested by vomiting, abdominal distention, delayed gastric emptying, esophageal reflux and decreased intestinal peristalsis, indicating that gastrointestinal dysfunction is a common phenomenon following TBI. Fasting is an effective manouver to reduce the incidence of gastric aspiration, but in emergency cases is rather difficult to establish that manouver. Several manouvers to reduce aspiration incidence are: a) to administer drugs prior to induction: histamine 2-reseptor antagonist (ranitidine, cimetidine), proton pump inhibitor (omeprazole), antacid (sodium citrate, magnesium trisilicate) and antiemetic (ondansentrone), b) head up position of 30-45o, c) rapid sequence induction with sellick manouver, d) insert naso or orogastric tube and aspirate gastric content. By using rapid sequence induction there would be not enough time to avoid the increase in blood pressure during laryngoscopy-intubation, whereas for patient with cerebral disorder including traumatic brain injury, increased blood pressure should be avoided because this will lead to increase intracranial pressure. Gastric content aspiration is one of anesthesia complication during perioperative periode especially in emergency cases. Adequate managment can reduce the incidency of aspiration.
Résumé
L’inhalation bronchique du contenu gastrique a été identifiée comme l’une des principales causes de mortalité et de morbidité liées à l’anesthésie dans les pays développés. L’utilisation de l’échographie antrale en temps réel est susceptible d’apporter une aide à l’anesthésiste pour l’évaluation du risque d’inhalation bronchique, dans le but de choisir la stratégie anesthésique la plus appropriée. L’évaluation échographique préopératoire du contenu gastrique pourrait être proposée chez tous les patients devant bénéficier d’une procédure chirurgicale en urgence. Les patients n’ayant pas respecté les règles de jeûne ou pour lesquels la durée de jeûne préopératoire est douteuse, ainsi que les patients présentant des conditions préopératoires susceptibles de ralentir la vidange gastrique (diabète, administration préopératoire d’opioïdes et insuffisance rénale chronique), pourraient également bénéficier d’une évaluation échographique du contenu gastrique avant une procédure chirurgicale programmée. Enfin, l’échographie antrale pourrait avoir un intérêt en cas de procédure obstétricale à la fin de la grossesse ou en postpartum immédiat. L’évaluation échographique du contenu gastrique peut donc avoir un intérêt pour l’orientation et l’individualisation de la stratégie anesthésique. Toutefois, l’impact potentiel de l’intégration de l’échographie antrale dans des algorithmes de décision clinique en pratique quotidienne sur l’incidence de l’inhalation bronchique et la morbi-mortalité périanesthésique reste à évaluer.
The present study aimed to investigate the effect of nursing guidelines on minimizing incidence rate of complications among cardiac catheterization patients. Data were collected from the cardiac catheterization unit at Assiut University Hospital. The study was conducted on 60 adult patients, having the following criteria; age between 20-65 years who were randomly assigned into two equal groups (study and control group) 30 patients for each group. The study group received the nursing guidelines, while the control group received routine hospital care. Data were collected through the following tools; Structure interviewing questionnaire, cardiac nursing guidelines based on individualized patient needs assessment and follow up sheet used for assessing complications. Results of this study; the majority of the studied sample were male, married, and more than half of them their age has ranged from (50 to 60 years), less than half of the studied sample were overweight and the incidence of local, respiratory and gastrointestinal complications was much more higher in the control group than in the study group. Conclusion; a highly statistical significant difference was found between both the study and the control group regarding incidence of local complications, pneumonia, gastrointestinal complications, while there was no statistical significant differences regarding circulatory and urinary complications. The study recommended that; a nursing guidelines booklet must be available to be applied for patients undergoing cardiac catheterization to decrease incidence rate of post cardiac catheterization complications.
A four‐month‐old, male dog underwent surgical repair of femoral and pelvic fracture. The dog was premedicated with acepromazine combined with morphine; anaesthesia was induced with propofol to effect and maintained with isoflurane in 100 per cent oxygen. One hour after induction the dog regurgitated and gastric contents emerged through the nares. At the end of the surgery rhinoscopy and oesophagoscopy were performed. The oesophageal mucosa was apparently normal, while posterior and retrograde rhinoscopy revealed diffused hyperaemia and oedema of the nasal cavity and nasopharyngeal mucosa; food particles and moderate amount of mucous exudates were also seen. Copious lavage was performed, and administration of antibiotics, metoclopramide, cimetidine and sucralfate was initiated. Nasal mucosa was re‐evaluated four days later. No abnormalities were detected in both nasal cavities and nasopharynx. The development of rhinitis following regurgitation during anaesthesia should be considered as a possible complication.
Image-guided renal biopsies have an increasing role in clinical practice. Renal mass and renal parenchymal biopsy indications, techniques, and other clinical considerations are reviewed in this article. Image-guided renal mass ablation shows significant promise and increasing clinical usefulness as more studies demonstrate its safety and efficacy. Renal mass ablation indications, techniques, and other considerations are also reviewed.
SUMMARY We have compared the effect of allowing free clear fluids until the time of oral premedication with conventional preoperative
fasting. In a prospective, randomized trial, the residual volume and pH of gastric contents after induction of anaesthesia
were measured in 100 elective surgical patients allocated randomly to a group in whom the intake of free clear fluids up to
the time of premedication was measured (mean 388 ml in 6 h before surgery) or a control group who were fasted for 6 h. Preoperative
drinking did not affect either mean (so) residual gastric volume (22 (21) ml in the study group vs 19 (16) ml in the control
group) or pH (study group 2.64 (1.57) vs control group 2.26 (1.45)). The study group experienced less preoperative thirst.
Problems with aspiration or regurgitation were not encountered. We believe that allowing elective surgical patients to drink
clear fluids until 2 h before anaesthesia may enhance patient comfort without compromising safety. (Br. J. Anaesth. 1993;
70: 6–9)
The acute effects of cigarette smoking on gastric emptying are controversial, whereas its effects on the intragastric distribution of solids and liquids are not established.
Dual isotope gastric scintigraphy was performed in 15 habitual smokers (studied twice, either sham smoking or actively smoking) and in 15 age- and sex-matched nonsmokers.
Acute smoking was associated with an increased prevalence of episodes of retrograde intragastric movement of solids (3 of 15 sham subjects vs. 12 of 15 actively smoking subjects; P < 0.01) and of liquids (0 of 15 vs. 7 of 15; P < 0.01) from distal to proximal stomach. Fundal half-emptying time (T1/2) for liquids was also prolonged by smoking (43 +/- 19 minutes sham vs. 125 +/- 216 minutes active; P < 0.05). Acute smoking delayed solid lag time (13 +/- 6 minutes sham vs. 32 +/- 18 active; P < 0.05) and liquid T1/2 (46 +/- 21 vs. 90 +/- 50 minutes; P < 0.05). In the nonsmokers, such episodes of proximal intragastric redistribution did not occur, and intragastric and overall emptying parameters did not differ significantly from those of habitual sham smokers.
Acute cigarette smoking produces excessive antrofundal redistribution of both solid and liquid contents and delays solid and liquid gastric emptying.
While intake of clear fluids 2–3 h before surgery is considered safe as it does not influence gastric content, it is not known if the same applies to a light breakfast meal. We therefore studied gastric emptying of a light breakfast in healthy, female volunteers without evidence of gastrointestinal motility disorders. The test meal consisted of one slice of buttered toast with jam, one cup of coffee without milk or sugar and one glass of pulp-free orange juice taken together with a paracetamol mixture. Using gastric ultrasonography, the stomach was identified without problems in all subjects, and gastric emptying curves using changes in gastric antral area and serum-paracetamol were obtained. Emptying of the fluid phase started immediately after intake of the meal. All subjects had solid particles in the stomach 120 min after the meal, 3 patients were considered empty after 180 min, 6 after 210 min and all after 240 min. The gastric antral area returned to fasting value significantly faster than the disappearance of solid particles; median 150 min versus 210 min; P=0.01. Our results show that in healthy subjects the stomach cannot be considered empty for solid particles the first 4 h after a light breakfast meal. To secure some safety limits, we suggest a 6-h mandatory preoperative fast after a light breakfast.
Acid aspiration in an important cause of anaesthetic mortality. 430 patients referred for gastric analysis were reviewed. According to observations made at endoscopy, patients were divided into 4 groups--no abnormality, oesophagitis/gastritis, gastric ulcers and duodenal ulcers. The volume of gastric juice varied from 0 to 400 ml, and the pH from 0-8 to 8. The percentage of patients with overnight fasting gastric volume over 25 ml and a pH of less than 2-5 was disturbingly high in all groups: controls 38-5%, oesophagitis/gastritis 51-2%, gastric ulcers 40-0%, duodenal ulcers 73-3%. This last figure is significantly greater than the group with no detectable abnormality. These results indicated that the stomach of a fasting patient often contains sufficient volume of acid gastric juice to place the subject at risk from acid aspiration during anaesthesia. Antacid therapy in all these patients seems imperative and consideration should also be given to preoperative gastric aspiration before induction of general anaesthesia.
Preoperative anxiety may increase gastric fluid acidity and volume. To pursue this possibility we evaluated the relationship between peroral premedication, preoperative anxiety, and gastric content in 246 consecutive patients presenting for elective gynecologic surgery. All patients fasted overnight and received either flunitrazepam 1 mg, oxazepam 25 mg, or placebo with 20 mL of water on the morning of surgery in a randomized, double-blind fashion. The patients assessed relief of anxiety using a four-graded scale (excellent, good, fair, poor). Both flunitrazepam and oxazepam decreased anxiety (P less than 0.01) compared with placebo. However, no correlations between type of premedication or level of anxiety and gastric contents were found. The proportion of patients with gastric fluid volume greater than 25 mL and pH less than 2.5 was not significantly different in any of the groups studied. These results suggest that neither peroral benzodiazepine premedication nor preoperative anxiety have a clinically important impact on gastric content in patients presenting for elective gynecologic surgery.
Gastro-oesophageal reflux during a 40-minute reflux provocation test was assessed by lower oesophageal pH monitoring in 25 pregnant women at term, and again on about the second day after delivery. At term 17 women refluxed a total of 29 times; after delivery five women refluxed once each. There was a significant decrease in gastro-oesophageal reflux by the second day after delivery (p less than 0.05). Gastro-oesophageal reflux is, however, only one of the factors that predisposes to acid aspiration pneumonitis.
Current knowledge of the physiology of gastric emptying implicates a reservoir function for the gastric fundus, grinding and propulsive functions for the antrum, and the concept of the pylorus and duodenum as resistances to gastroduodenal flow. Although these areas differ markedly in their behavior, their contractile activities are coordinated in such a way that the delivery of nutrients to the small intestine occurs in an orderly and controlled manner. In this article we describe the functions of the gastric fundus, antrum, pylorus, and duodenum and how the contractile activities of these regions regulate gastric emptying, according to the composition of the meal and the physiologic and emotional state of the person. In addition we discuss the nature and possible mechanisms of the motor disturbances associated with abnormally slow gastric emptying.
One hundred and twenty healthy, elective surgical inpatients were randomly assigned to one of four groups. Between two and three hours before the scheduled time of surgery all patients ingested a marker dye, phenol red, 50 mg in 10 ml water, with placebo tablet alone (Groups 1 and 2), placebo tablet with 150 ml oral fluid (Group 3), or oral ranitidine 150 mg with oral fluid 150 ml (Group 4). Patients in Group 1 received oral diazepam or no premedication, while those in Groups 2, 3, and 4 received IM narcotic and atropine one hour preoperatively. Following induction of anaesthesia the residual gastric fluid was aspirated through a Salem sump tube and its volume, pH, and phenol red content measured. Mean volumes were Group 1: 24 ml; Group 2: 13 ml; Group 3: 17 ml; Group 4: 14 ml. Mean pH values were Group 1: 2.99; Group 2: 3.03; Group 3: 3.44; Group 4: 5.28. The amount of phenol red in the samples indicated at least 90 per cent gastric emptying had occurred in 90 per cent of patients. We conclude that, in healthy patients, 150 ml oral fluid is almost completely emptied from the stomach within two hours of ingestion, even when followed one hour later by narcotic-atropine premedication.
In order to estimate the incidence and significance of aspiration during anaesthesia, a study of cases in which this complication had occurred was made at the Karolinska Hospital. With the aid of the anaesthetic recordkeeping system of the Department of Anaesthesia and the computer-based register of diagnoses of in-patients at the hospital, all cases in which aspiration was recorded were retrieved. Eighty-three cases of aspiration were retrieved from the file of anaesthetic records and four from the in-patient register. This constitutes an incidence of 4.7 aspirations in 10 000 anaesthetics, or 1 in 2131. The patients most often affected were children and the elderly. In 83% of the cases there were one or more preoperative factors indicating an increased risk for aspiration, such as emergency operation (38 cases, 43%), upper abdominal or emergency abdominal surgery (14 cases, 16%), a history indicating delayed gastric emptying (e.g. peptic ulcer/gastritis, pregnancy, obesity, unusual stress or pain, elevated intracranial pressure, 54 cases, 61%). In 29 cases (33%) there was a history indicating an increased risk of regurgitation, e.g. nasogastric tube, oesophageal disease or pregnancy. In 15 cases of elective surgery, no history of increased risk for aspiration could be found. In 67% of those cases the aspiration was preceded by difficulties involving the airways or intubation. The incidence of aspiration was more than sixfold higher during the night than during regular daytime working hours. In 41 cases (47%) the aspiration led to aspiration pneumonitis confirmed by x-ray. Fifteen patients (17%) needed mechanical ventilation, and four died.(ABSTRACT TRUNCATED AT 250 WORDS)
The effect of a gastric tube on the competence of the lower esophageal sphincter was studied in 7 patients who underwent gastric resection. In 6 patients the maximal gastric volume until occurrence of regurgitation was lower in the presence of a gastric tube compared with the measurement without a tube. This shows the necessity to remove a gastric tube prior to induction of anaesthesia.
The gastric emptying characteristics of physiological saline (0.9% NaCl) and glucose solutions of three different concentrations (0.05, 0.125, 0.25 g/ml) were examined in order to identify distinctions in the control of the stomach's activity. Saline emptied rapidly and exponentially. Glucose assumed, soon after filling the stomach, a slow and calorie-constant emptying pattern such that 2.13 kcal of glucose were delivered per minute to the duodenum for all three concentrations of glucose. When, by means of a catheter passed beyond the pylorus, glucose was infused into the duodenum in amounts varying from 26.5 to 120 kcal, an inhibition on the gastric emptying of physiological saline of 0.46 min/kcal of intraduodenal glucose was demonstrated. Since 2.13 kcal/min and 0.46 min/kcal are reciprocals, it appeared that in emptying saline, the gastroduodenal system acts as an "open-loop" system passing liquids from the stomach at a rate primarily determined by the volume of gastric contents. With glucose, however, a "closed-loop" system is established that assumes a steady-state balance between the delivery of glucose to the duodenum and the inhibition of this delivery evoked from the duodenum by the glucose that enters it.
Children admitted for emergency operations because of trauma run a high risk of chemical aspiration pneumonitis syndrome. Fifty-eight children admitted for closed reduction of fractures and suturing of wounds were studied in a double-blind manner in order to see if metoclopramide could be of value in decreasing the risk of aspiration during anaesthesia. Metoclopramide given before anaesthesia proved to enhance gastric evacuation and could thus be of value in these situations. In addition, the study showed that the time from last oral intake until start of anaesthesia is of less importance then the type of trauma in prolonging the gastric emptying time and thus increasing the risk of vomiting and aspiration of vomitus into the lungs during anaesthesia.
Twelve randomised studies of preoperative intake of clear fluids and gastric content were reviewed and presented together with a separate study performed by the authors. A common deficiency in design was the omission of detailed information concerning randomisation procedures, distribution of data, and choice of statistical methods. Only one reviewed study included power calculations and only 3 reported 95% C.I. (Confidence Intervals). Deficiencies in design and data collection rendered the conclusion of two studies invalid. Incorrect use of statistical tests in some of the remaining studies may have resulted in non-significant differences becoming statistically significant. This, however, did not change the main conclusion of a meta-analysis that intake of clear fluids up to 2 hours before general anaesthesia was safe as fluid intake either decreased or had no effect on gastric fluid volume.
To study the effects on gastric content and subjective well being of chewing gum in the immediate preoperative period, 60 female nonsmokers were randomized to use regular, sugar-free chewing gum preoperatively or to continue the overnight fast. In a similar fashion 44 habitual smokers were randomized to use nicotine gum 2 mg or not. Nonsmokers using chewing gum had significantly larger gastric fluid volumes than controls (mean 30 +/- 19 mL vs 20 +/- 15 mL; 95% confidence interval (CI) for difference 1-19 mL; P = 0.03), with no difference in gastric fluid acidity. In smokers, neither gastric fluid volume nor acidity differed significantly between those who were or were not chewing gum. Although the use of nicotine gum in smokers was associated with a reduction in dryness of the mouth, thirst, and irritability, nonsmokers chewing regular gum did not report significant improvements in patient well being. In habitual smokers unable to abstain from nicotine, the use of nicotine gum on the morning of surgery may be beneficial. Although it is difficult to prove a direct influence on the incidence of pulmonary aspiration of increased gastric contents, the fact that regular, sugar-free chewing gum increased gastric fluid volumes probably means that it should not be used on the morning of surgery.
Disturbed antroduodenal motility plays an important role in the pathophysiology of functional dyspepsia (FD). Such motility disturbances can be investigated by transcutaneous ultrasound. When it is measured in a standardized section, patients with FD have on an average significantly larger antral area than healthy controls.
In this study we investigated the relationship between the antral area measured by ultrasound and the amount of fasting gastric content quantitated by aspiration through the gastroscope in 30 patients. In five healthy controls we measured the increment of the antral area after ingestion of graded volumes of water. All recordings were made in interdigestive phase I.
Measurements of the antral area were highly reproducible, with small variations within an hour and from day to day. There was a highly significant correlation between ultrasonographically measured antral area and amount of fasting gastric juice and between increment of antral area and amounts of ingested water.
The ultrasonographically measured antral area during fasting is highly reproducible. Enlarged fasting antral area reflects increased volume of gastric juice.
Gastric emptying was studied indirectly by paracetamol absorption in 20 patients at 87–12 weeks' gestation and also in 20
non-pregnant controls. Subjects received paracetamol 1.5 g in a tablet with 50 ml of water and remained semi-recumbent for
2 h while venous blood samples were obtained at 15-min intervals. The maximum concentration of paracetamol was significantly
lower and the time to maximum concentration significantly greater in pregnant patients. In addition, the areas under the time-concentration
curves at 60 and 120 min were significantly smaller in the pregnant group. These changes are indicative of a delay in gastric
emptying at 8–12 weeks' gestation.
Pulmonary aspiration of gastric contents during the perioperative period may be associated with postoperative mortality or pulmonary morbidity. Recent determination of the incidence of perioperative pulmonary aspiration and evaluation of factors related to clinical outcomes is lacking.
We retrospectively reviewed the perioperative courses of 172,334 consecutive patients 18 yr of age or older who underwent 215,488 general anesthetics for procedures performed in all surgical specialties from July 1985 to June 1991. Pulmonary aspiration was defined as either the presence of bilious secretions or particulate matter in the tracheobronchial tree or, in patients who did not have their tracheobronchial airways directly examined after regurgitation, the presence of an infiltrate on postoperative chest roentgenogram that was not identified by preoperative roentgenogram or physical examination.
Pulmonary aspiration occurred in 67 patients (1:3,216 anesthetics). Fifteen aspirations occurred in 13,427 (1:895) anesthetics of patients undergoing emergency surgery, and 52 occurred in 202,061 (1:3,886) anesthetics of patients undergoing elective surgery (P < .001). Of the 66 patients who survived their surgery, 42 (64%) did not develop a cough or wheeze, a decrease in arterial hemoglobin oxygen saturation while breathing room air > 10% less than the preoperative value, or radiographic abnormalities within 2 h of aspiration. These 42 patients had no respiratory sequelae. Of the 24 patients who had one or more of these findings, 13 required mechanical ventilatory support for more than 6 h. Three of the six patients whose lungs required mechanical ventilation for more than 24 h died from pulmonary insufficiency (overall mortality = 1:71,829 anesthetics).
This study suggests that patients with clinically apparent aspiration who do not develop symptoms within 2 h are unlikely to have respiratory sequelae.
In a controlled study, gastric emptying was measured during the three trimesters of pregnancy and after delivery, using an indirect paracetamol absorption technique. The peak plasma paracetamol concentration, time to reach the peak, and the area under the plasma paracetamol concentration-time curve, were determined. As compared to nonpregnant controls, there were no significant differences in the gastric emptying times of women in the three trimesters of pregnancy and of mothers from 18 h after delivery onwards. Gastric emptying was significantly delayed in mothers within 2 h after delivery (p < 0.01); median (range) values of peak paracetamol concentration, time to reach the peak and the area under the paracetamol concentration-time curve for this group were 12.5 (0.2-30.5) mg.l-1, 120 (30-120) min and 3.8 (0.1-16.6) mg.l-1 x h respectively, and 20.8 (8.6-64.5) mg.l-1, 40 (10-120) min and 13.5 (5.5-28.8) mg.l-1 x h respectively, for the nonpregnant control group (p < 0.01). Repeated measurements of gastric emptying in these women on the second postpartum day showed no significant delay.
Overnight fasting is routine before elective surgery. This may not be the optimal way to prepare for surgical stress, however, because intravenous carbohydrate supplementation instead of fasting has recently been shown to reduce postoperative insulin resistance. In the current study, gastric emptying of a carbohydrate-rich drink was investigated before elective surgery and in a control situation.
Twelve patients scheduled for elective surgery were randomly given 400 mL of either a carbohydrate-rich drink (285 mOsm/kg, 12.0% carbohydrates, n = 6) or water 4 hours before being anesthetized. Gastric emptying was measured (gamma camera, 99Tcm). Each patient repeated the protocol postoperatively as a control. All values were presented as the mean +/- SEM by means of a nonparametric statistical evaluation.
Despite the increased anxiety experienced by patients before surgery (p < 0.005), gastric emptying did not differ between the experimental and control situations. Initially, water emptied more rapidly than carbohydrate. However, after 90 minutes, the stomach was emptied regardless of the solution administered (3.2 +/- 1.1% [mean +/- SEM] remaining in the stomach in the carbohydrate group versus 2.3 +/- 1.2% remaining in the stomach in the water group).
Preoperative anxiety does not prolong gastric emptying. The stomach had been emptied 90 minutes after ingestion of both the carbohydrate-rick drink and water, thereby indicating the possibility of allowing an intake of iso-osmolar carbohydrate-rich fluids before surgery.
Obstetric patients are considered to be at increased risk of anaesthesia-related Aspiration Pneumonitis. Less is known about the incidence and morbidity of this complication in younger women undergoing gynaecological surgery. We performed a 4-year audit of perioperative Aspiration Pneumonitis, defined as bronchospasm, hypoxia, cough and dyspnea, together with radiographic or auscultatory abnormalities, following a witnessed episode of gastric content entering the trachea or an intraoperative episode making pulmonary aspiration likely, in two larger Norwegian hospitals. Eleven cases were identified; 4 in Caesarean Section (C-section) patients, 5 in gynaecological (GYN) outpatients and 2 in GYN inpatients, with incidences of 0.11%, 0.04% and 0.01% respectively (P = 0.03). Risk factors were present in all patients. No patient died, but the short-time morbidity in the form of prolonged ICU stay and hospitalisation was significant. At discharge all patients noted symptoms of dyspnea, cough, and tightness of the chest; symptoms explainable by bronchial hyperreactivity. Five patients felt these symptoms did not disappear within 3 months and were followed up for a median of 2 years (range 4 months to 4 years). All were smokers and had multiple confounding causes, which made it hard to link their prolonged complaints directly to the pulmonary aspiration incident. All experienced improvement of symptoms during the follow-up period. Compared to gynaecological patients of similar age, C-section patients still have an increased risk of suffering Aspiration Pneumonitis. Prevention can be further improved in both groups. A cause-relationship between the incidence and respiratory complaints lasting longer than 3 months could not be established, and a structured follow-up may be helpful to avoid later medicolegal claims.
Abstention from food and drink prior to anaesthesia remains a cornerstone in safe practice. Despite the lack of scientific support, previous guidelines, similar for fluids and solids, have for more than three decades more often than not recommended "nil by mouth" ("nothing-per-os"; "NPO" in the US) after midnight or a fixed duration of time. Based on an increased number of studies of relevance to the duration of preoperative fasting, reviews on this subject concerning both adults (1) and children (2) and a large number of editorials (3-7), have recently been published. Since there may be a discrepancy between conclusions based on scientific studies and the current routine practice-this presentation is intended to survey the current recommendations in different countries and how they relate to publications on the subject. Opinions are mainly derived from officers of associations linked to The World Federation for Anaesthesiologists (WFSA) and from current literature.
The aim of this study was to determine the incidence and severity of pulmonary aspiration of gastric contents during anaesthesia, to determine the short- and long-term morbidity, and to evaluate present routines for preoperative gastric emptying. During the study period, preoperative gastric emptying was done only when intestinal obstruction was suspected.
We routinely record prospectively all problems during and after anaesthesia by means of a database. All data for the 5 years from 1989 to 1993, a total of 85594 anaesthetic procedures, were analyzed. The hospital charts were also reviewed for those patients where aspiration to the lungs had occurred.
Pulmonary aspiration of gastric contents was detected in 25 cases; all occurred in patients receiving general anaesthesia. The incidence was 4.1 times higher in emergency procedures than in electives. There were no aspirations in 30199 patients receiving regional anaesthesia. The complication occurred in all phases of anaesthesia, but clinical morbidity was low in most cases. Three cases showed serious morbidity immediately after the event, but recovered. Two cases showed serious long-term morbidity, but also recovered completely. No patients died. No cases, except possibly one, might have been prevented by stricter routines for preoperative gastric emptying.
We found a low incidence of pulmonary aspiration. When it occurs, it carries a low risk for serious morbidity. Emergency cases for general anaesthesia are most at risk. Regional anaesthesia is considered safe. There is no evidence that preoperative gastric emptying should be routinely done in emergency cases, except in patients with suspected ileus/ subileus.
This article reviews the application of magnetic resonance imaging (MRI) to study the gastrointestinal (GI) tract. A summary of the current MRI techniques is included, emphasizing the choice of pulsing sequences, imaging plane, surface coils and intravenous and oral contrast agents for each of the different segments of the GI tract. The multiple available oral contrast agents are reviewed, including the role of both positive and negative. Finally, the major clinical applications of MRI in the GI tract are discussed by major disease categories (congenital abnormalities, inflammatory disease and benign and malignant neoplasms). The latter is further subdivided by GI tract segments such as esophagus, stomach, small bowel and colon.
Liberalisation of preoperative fasting rules has been discussed and recommended in the anaesthesia literature in recent years. In Norway, a national consensus on this issue was reached in 1993. The aim of the present study was to investigate whether a national consensus on fasting recommendations led to a change in fasting policies in Norwegian anaesthesia departments.
A questionnaire on preoperative fasting routines was sent to all Norwegian anaesthesia departments in 1993 and repeated in 1996.
Written local guidelines for preoperative fasting were present in 85% of the institutions in both surveys. Of the hospitals, 69% had changed their local guidelines after the national consensus. In 1996 more hospitals allowed less than 6 h fasting for clear liquids in children (93% versus 71% in 1993; P < 0.005). A similar tendency was noted in adults (79% versus 63% in 1993; P = 0.1). In contradiction to the national guidelines, 31% of the departments reported that they allowed less than 6 h fasting after a light breakfast in the morning of surgery in 1996. The corresponding number for 1993 was 21% (ns).
The new, consensus-based national fasting guidelines have been associated with a change towards more liberal fasting policies in Norwegian departments of anaesthesia. However, as not all local changes were supported by the national consensus, other sources of information were used when local policies were decided.
Two-hundred and forty incidents of vomiting/regurgitation and aspiration were reported to the Anaesthetic Incident Monitoring Study database consisting of 5000 reports. Of these, 133 cases of aspiration were recorded. Passive regurgitation occurred three times more commonly than active vomiting. Aspiration was reported twice as often in elective compared with emergency surgery, with 56% of incidents taking place during induction of anaesthesia. Anti-aspiration prophylaxis was prescribed in 14% of patients who subsequently aspirated; however, the majority of cases had at least one predisposing factor for regurgitation, vomiting or aspiration evident peri-operatively. While a major immediate physiological disturbance was common, long-term morbidity was not. Death ensued in five cases, all of whom had significant co-morbidities. Factors reported as contributing to the incident included error of judgement and fault of technique, while clinical experience and anaesthetic assistance tended to minimise the incident. Aspiration remains an important anaesthetic-related morbidity. The application of simple guidelines may have prevented the incident in 60% of all cases of aspiration. Ensuring airway security may be as important as chemoprophylaxis in its prevention.
The aim of this study was to determine whether permitting women in labour to eat a light diet would: (i) alter their metabolic profile, (ii) influence the outcome of labour, and (iii) increase residual gastric volume and consequent risk of pulmonary aspiration. Women were randomised to receive either a light diet (eating group, n = 48) or water only (starved group, n = 46) during labour. The light diet prevented the rise in plasma beta-hydroxybutyrate (p = 2.3 x 10(-5)) and nonesterified fatty acids (p = 9.3 x 10(-7)) seen in the starved group. Plasma glucose (p = 0.003) and insulin (p = 0.017) rose in the eating group but there was no difference in plasma lactate (p = 0.167) between the groups. There were no differences between the groups with respect to duration of first or second stage of labour, oxytocin requirements, mode of delivery, Apgar scores or umbilical artery and venous blood samples. Relative gastric volumes estimated by ultrasound measurement of gastric antral cross-sectional area were larger (p = 0.001) in the eating group. This was supported by the observation that those from this group who vomited, vomited significantly larger volumes than those in the starved group (p = 0.001). We conclude that eating in labour prevents the development of ketosis but significantly increases residual gastric volume.
The effect of nicotine on gastric emptying remains controversial. Gastric emptying is delayed in chronic smokers after smoking high-dose nicotine cigarettes, but it is unchanged after chewing nicotine gums. No information is available on the effect of transdermal nicotine patches on the gastric emptying of solid and liquid contents in healthy nonsmokers. Our objective was to prospectively evaluate the effect of the nicotine patch on gastric emptying of liquid and solid contents in healthy nonsmokers. Ten healthy nonsmoking volunteers underwent a baseline dual-isotope gastric scintigraphy with [111In]-diethylenetriaminepantaacetic acid (DTPA) and [99mTc]sulfur colloid isotopes to evaluate prospectively the gastric emptying of liquid and solid contents, respectively. The gastric scintigraphy was repeated after placing a transdermal nicotine patch (Habitrol) for 12 hr designed to deliver 14 mg of nicotine per day. Plasma nicotine level was measured prior to baseline gastric scintigraphy and after 12 hr placing the nicotine patch. Plasma nicotine was absent in all subjects at baseline and but was significantly elevated after 12 hr of nicotine patch (P < 0.009). The mean half-emptying times (T1/2) for the gastric emptying of liquids before and after nicotine patch placement were 31.2+/-23.3 and 25.6+/-8.4 min, respectively (P = 0.498). The mean T1/2s for the gastric emptying of solids before and after nicotine patch placement were 70.1+/-34.0 and 59.7+/-31.4 min, respectively (P = 0.202). There was no correlation between the plasma nicotine level and gastric emptying of liquid and solid contents (correlation coefficient = -0.23 and -0.01, respectively). In conclusion, acute transdermal delivery of nicotine does not affect the gastric emptying of solid and liquid contents in healthy nonsmoking subjects.
Regardless of the type and dose of beverage involved, alcohol facilitates the development of gastroesophageal reflux disease by reducing the pressure of the lower esophageal sphincter and esophageal motility. Fermented and nondistilled alcoholic beverages increase gastrin levels and acid secretion. Succinic and maleic acid contained in certain alcoholic drinks also stimulate acid secretion. Low alcohol doses accelerate gastric emptying, whereas high doses delay emptying and slow bowel motility. Alcohol facilitates the development of superficial gastritis and chronic atrophic gastritis--though it has not been shown to cause peptic ulcer. Alcoholic beverages, fundamentally wine, have important bactericidal effects upon Helicobacter pylori and enteropathogenic bacteria. The main alcohol-related intestinal alterations are diarrhea and malabsorption, with recovery after restoring a normal diet. Alcohol facilitates the development of oropharyngeal, esophageal, gastric, and colon cancer. Initial research suggests that wine may be comparatively less carcinogenic.
Postoperative insulin resistance is a well-characterized metabolic state that has been shown to correlate with the length of postoperative stay in hospital. Preoperative intravenous or oral carbohydrate treatment has been shown to attenuate the development of postoperative insulin resistance measured 1 day after surgery. To study the effects of preoperative oral carbohydrate treatment on postoperative changes in insulin resistance and substrate utilization, in the absence of postoperative confounding factors, 15 patients were double-blindly treated with either a carbohydrate-rich beverage (12.5%) (n = 8) or placebo (n = 7) before undergoing total hip replacement surgery. Insulin sensitivity, endogenous glucose release, and substrate oxidation rates were measured before and immediately after surgery. Whole body insulin sensitivity decreased by 18% in the treatment group vs. 43% in the placebo group (P < 0.05, Student's t-test for unpaired data). In both groups, the major mechanism of insulin resistance was an inhibition of insulin-induced nonoxidative glucose disposal after surgery. The better preservation of insulin sensitivity in the treatment group was attributable to a less reduced glucose disposal in peripheral tissues and increased glucose oxidation rates.
Members of the British Ophthalmic Anaesthesia Society were surveyed using a postal questionnaire. The response rate was 72.3%. Respondents were asked about starvation before regional anaesthesia for cataract surgery, the use of sedation in these patients, monitoring and if oxygen supplementation was given. The results show that most patients are not starved before this type of regional anaesthesia, and that the majority of patients receive no supplementary sedation or intravenous analgesia. Over 70% of patients received oxygen supplementation.
Unlabelled:
We studied the effects of different preoperative oral fluid protocols on preoperative discomfort, residual gastric fluid volumes, and gastric acidity. Two-hundred-fifty-two elective abdominal surgery patients (ASA physical status I-II) were randomized to preparation with a 12.5% carbohydrate drink (CHO), placebo (flavored water), or overnight fasting. The CHO and Placebo groups were double-blinded and were given 800 mL to drink on the evening before and 400 mL on the morning of surgery. Visual analog scales were used to score 11 different discomfort variables. CHO did not increase gastric fluid volumes or affect acidity, and there were no adverse events. The visual analog scale scores in a control situation were not different between groups. During the waiting period before surgery, the CHO-treated group was less hungry and less anxious than both the other groups (P < or = 0.05). CHO reduced thirst as effectively as placebo (P < 0.0001 versus Fasted). Trend analysis showed consistently decreasing thirst, hunger, anxiety, malaise, and unfitness in the CHO group (P < 0.05). The Placebo group experienced decreasing unfitness and malaise, whereas nausea, tiredness, and inability to concentrate increased (P < 0.05). In the Fasted group, hunger, thirst, tiredness, weakness, and inability to concentrate increased (P < 0.05). In conclusion, CHO significantly reduces preoperative discomfort without adversely affecting gastric contents.
Implications:
Discomfort during the period of waiting before elective surgery can be reduced if patients are prepared with a carbohydrate-rich drink, compared with preoperative oral intake of water or overnight fasting. Visual analog scales can provide useful information about preoperative discomfort in elective surgery patients.
The assessment of pre-procedure fasting and control of sedation depth are prominent elements of widely disseminated procedural sedation guidelines and of the Joint Commission on Accreditation of Healthcare Organizations' standards. Both exist primarily to minimize the risk of pulmonary aspiration of gastric contents. This paper critically examines the literature on pre-procedure fasting and controlling sedation depth in association with pulmonary aspiration, and interprets this evidence in the context of modern emergency medicine practice. The article reviews the pathophysiology of aspiration and changing concepts regarding aspiration risk over the last decade. After reviewing studies on aspiration risk during general anesthesia, the paper reviews the risk of aspiration during labor and delivery as a more appropriate comparison group for aspiration risk during emergency department procedural sedation and analgesia (ED PSA). It is noted that aspiration during ED PSA has not been reported in the medical literature and that aspiration during general anesthesia and labor and delivery is uncommon. The literature provides no compelling evidence to support specific fasting periods for either liquids or solids prior to PSA, and existing guidelines for elective patients are of necessity arbitrary and based upon consensus opinion. The article discusses the implications in the areas of training and preparedness, monitoring, and research for the emergency physician practicing PSA.
The outcome of recent studies has led to redefinition of concepts relating to the prevalence, pathogenesis and clinical significance of disordered gastric emptying in patients with diabetes mellitus. The use of scintigraphic techniques has established that gastric emptying is abnormally slow in approx. 30-50% of outpatients with long-standing Type 1 or Type 2 diabetes, although the magnitude of this delay is modest in many cases. Upper gastrointestinal symptoms occur frequently and affect quality of life adversely in patients with diabetes, although the relationship between symptoms and the rate of gastric emptying is weak. Acute changes in blood glucose concentration affect both gastric motor function and upper gastrointestinal symptoms. Gastric emptying is slower during hyperglycaemia when compared with euglycaemia and accelerated during hypoglycaemia. The blood glucose concentration may influence the response to prokinetic drugs. Conversely, the rate of gastric emptying is a major determinant of post-prandial glycaemic excursions in healthy subjects, as well as in Type 1 and Type 2 patients. A number of therapies currently in development are designed to improve post-prandial glycaemic control by modulating the rate of delivery of nutrients to the small intestine.
To avoid pulmonary aspiration, fasting after midnight has become standard in elective surgery, but recent studies have found no scientific support for this practice. Several anaesthesia societies now recommend a 2-h preoperative fast for clear fluids and a 6-h fast for solids in most elective patients. The literature supporting such fasting recommendations was reviewed.
The recommendations are safe and improve well-being before operation, mainly by reducing thirst. A carbohydrate-rich beverage given before anaesthesia and surgery alters metabolism from the overnight fasted to the fed state. This reduces the catabolic response (insulin resistance) after operation, which may have implications for postoperative recovery.
Most patients having elective operations can be allowed a free intake of clear fluids up to 2 h before anaesthesia. Preoperative carbohydrates reduce postoperative insulin resistance.
Delayed gastric emptying occurs frequently in patients with upper gastrointestinal symptoms associated with functional or organic diseases.
To evaluate whether: (i) the prevalence of delayed gastric emptying is influenced by the presence of organic disease; (ii) demographic or clinical factors predict modestly or markedly (gastroparesis) delayed emptying.
A total of 327 consecutive out-patients with upper gastrointestinal symptoms.
Routine diagnostic work-up and evaluation of demographic factors, gastrointestinal symptom evaluation and scintigraphic gastric emptying of solids were performed.
Organic diseases were detected in 227/327 (65%) patients: 33% had delayed emptying and 20% gastroparesis. Female gender (OR: 2.1; 95% C.I.: 1.3-3.4). overweight (0.5; 0.3-0.9), relevant postprandial fullness (1.8; 1.1-3.2) and relevant epigastric bloating (1.8; 1.1-2.9), but not the presence of organic diseases, were associated with delayed emptying. Female gender (3.9; 1.3-11.9) and relevant postprandial fullness (4.1; 1.7-10.2) were associated with gastroparesis.
(i) There is a high prevalence of delayed gastric emptying and gastroparesis in out-patients with upper gastrointestinal symptoms, which is not influenced by the presence of organic disease; (ii) female gender, low body weight, relevant fullness and bloating are associated with delayed emptying; female gender and relevant postprandial fullness predict gastroparesis.
Over the last years several clinical studies have modified the guidelines for preoperative fasting to reduce the risk of pulmonary aspiration. In most western countries the following guidelines are accepted: for clear liquids 2 hours, breast feeding 4 hours, small meals and breast milk substitutes 6 hours, heavy meals 8 hours. Since preoperative smoking is acknowledged as a risk factor, it should be ceased in most clinics 6 hours before induction of anaesthesia, as well. Smoking, however, does not increase the risk of pulmonary aspiration, as is often maintained, but increases the risk of postoperative pulmonary complications. To reduce the risk of perioperative pulmonary complications, cessation of smoking is necessary 8 weeks before operation. Stopping smoking only a few days before operation and anaesthesia even tends to increase the risk of pulmonary complications. Regarding cardiac complications, cessation of smoking 12 hours before anaesthesia is sufficient to reduce the incidence of cardiac ischaemia.
To determine whether, in obese [body mass index (BMI) > 30 kg.m(2)] patients, oral intake of 300 mL clear liquid two hours before elective surgery affects the volume and pH of gastric contents at induction of anesthesia.
A single-blind, randomized study of 126 adult patients, age > or = 18 yr, ASA physical status I or II, BMI > 30 kg.m(2) who were scheduled for elective surgery under general anesthesia. Patients were excluded if they had diabetes mellitus, symptoms of gastroesophageal reflux, or had taken medication within 24 hr that affects gastric secretion, gastric fluid pH or gastric emptying. All patients fasted from midnight and were randomly assigned to fasting or fluid group. Two hours before their scheduled time of surgery, all patients drank 10 mL of water containing phenol red 50 mg. Those in the fluid group followed with 300 mL clear liquid of their choice. Immediately following induction of general anesthesia and tracheal intubation, gastric contents were aspirated through a multiorifice Salem sump tube. The fluid volume, pH and phenol red concentration were recorded.
Median (range) values in fasting vs fluid groups were: gastric fluid volume 26 (3-107) mL vs 30 (3-187) mL, pH 1.78 (1.31-7.08) vs 1.77 (1.27-7.34) and phenol red retrieval 0.1 (0-30)% vs 0.2 (0-15)%. Differences between groups were not statistically significant.
Obese patients without comorbid conditions should follow the same fasting guidelines as non-obese patients and be allowed to drink clear liquid until two hours before elective surgery, inasmuch as obesity per se is not considered a risk factor for pulmonary aspiration.
In Germany the predominant standard of preoperative care for elective surgery is fasting after midnight, with the aim of reducing the risk of pulmonary aspiration. However, for the past several years the scientific evidence supporting such a practice has been challenged. Experimental and clinical studies prove a reliable gastric emptying within 2 h suggesting that, particularly for limited intake of clear fluids up to 2 h preoperatively, there would be no increased risk for the patient. In addition, the general incidence of pulmonary aspiration during general anaesthesia (before induction, during surgery and during recovery) is extremely low, has a good prognosis and is more a consequence of insufficient airway protection and/or inadequate anaesthetic depth rather than due to the patient's fasting state. Therefore, primarily to decrease perioperative discomfort for patients, several national anaesthesia societies have changed their guidelines for preoperative fasting. They recommend a more liberal policy regarding per os intake of both liquid and solid food, with consideration of certain conditions and contraindications. The following article reviews the literature and gives an overview of the scientific background on which the national guidelines are based. The intention of this review is to propose recommendations for preoperative fasting regarding clear fluids for Germany as well.