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ABSTRACT: The goal of this project was to identify key effective components of ADVANCE, a family-centred preoperative intervention programme, through the use of a dismantling approach. ADVANCE was previously demonstrated to be more effective than parental presence and just as effective as midazolam in reducing children's preoperative anxiety. The total programme, however, may be difficult to implement in hospitals across the country.
Subjects in this follow-up dismantling report were 96 children aged 2-10 who were part of the original study and who underwent anaesthesia and surgery. Baseline characteristics, parental adherence to the components of ADVANCE, and child and parent anxiety were assessed.
We found that greater parental adherence to the ADVANCE intervention was associated with lower child anxiety before surgery. The two components of ADVANCE that emerged as having a significant impact on children's anxiety were practising with the anaesthesia mask at home and parental planning and use of distraction in the preoperative holding area. In fact, not only did children experience significantly less preoperative anxiety when their parents were adherent to mask practise and use of distraction, their anxiety tended to remain stable and relatively low throughout the preoperative period.
Shaping and exposure (i.e. practise with the anaesthesia mask) and parental use of distraction in the surgical setting are two beneficial components that could be included in preoperative preparation programmes that will be designed in the future.
BJA British Journal of Anaesthesia 02/2011; 106(5):713-8. · 4.24 Impact Factor
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Anesthesia & Analgesia 12/2001; 93(5):1178-80, table of contents. · 3.29 Impact Factor
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Anesthesia & Analgesia 08/2001; 93(1):98-105. · 3.29 Impact Factor
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Z N Kain
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ABSTRACT: Up to 60% of all children undergoing anesthesia and surgery experience significant anxiety and distress during the perioperative period. Currently, both behavioral interventions such as parental presence during induction of anesthesia and pharmacological interventions such as sedative premedication are used to treat this clinical phenomenon. In this review, we examine the effectiveness of these interventions on clinically relevant perioperative outcomes.
Current Opinion in Anaesthesiology 07/2001; 14(3):331-7. · 2.21 Impact Factor
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ABSTRACT: We assessed the effectiveness of a behavioral intervention aimed at reducing the anxiety of children undergoing anesthesia and surgery. The intervention consisted of dimmed operating room (OR) lights (200 Lx) and soft background music (Bach's "Air on a G String," 50-60 dB). Only one person, the attending anesthesiologist, interacted with the child during the induction of anesthesia. Children undergoing anesthesia and surgery were randomly assigned either to a low sensory stimulation group (LSSG, n = 33) or to control group (n = 37). By using validated behavioral measures of anxiety (mYPAS) and compliance (ICC), children were evaluated at the preoperative holding area and during the induction of anesthesia. On postoperative Days 1, 2, 3, 7, and 14, the behavioral recovery of the children was assessed by using the Post Hospitalization Behavior Questionnaire. We found that the LSSG was significantly less anxious compared with the control group on entrance to the OR (P = 0.03) and on the introduction of the anesthesia mask (P = 0.003). Also, the compliance during the induction of anesthesia was significantly better in children assigned to the LSSG (P = 0.02). The incidence of postoperative behavioral changes, however, did not differ significantly between the two groups (P = ns). We conclude that children who are exposed to low-level sensory stimuli during the induction of anesthesia and who are exposed to background music exhibit lower levels of anxiety and increased compliance. IMPLICATIONS: Children are less anxious and show increased compliance during induction when exposed to a single care-provider in a dimmed, quiet operating room with background music.
Anesthesia & Analgesia 05/2001; 92(4):897-903. · 3.29 Impact Factor
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ABSTRACT: Every year, millions of patients receive sedatives for reduction of anxiety before surgery, but there is little objective data on the effect of this treatment on postoperative outcomes. To address this issue, the effects of benzodiazepine administration were evaluated in women undergoing abdominal surgery.
Patients were randomized to receive 1 mg of oral lorazepam the night before surgery and 5 mg of intramuscular midazolam on the morning of surgery (n = 34), or to receive a placebo the night before surgery and on the morning of surgery (n = 36). Postoperative pain (Visual Analogue Scale for pain, McGill Pain Questionnaire) and analgesic consumption (patient-controlled analgesia), and clinical recovery parameters such as time to discharge from hospital were evaluated after surgery.
Patient-controlled analgesia use showed a marginal main effect of treatment group (F(1,51) = 2.8; P = 0.047). Post boc analysis demonstrated that patient-controlled analgesia consumption was significantly lower in the treatment group only during the first 4 h of patient-controlled analgesia use after surgery (P = 0.027). There were no significant group differences at any later postoperative time points (P = not significant). There were no group differences in the cumulative Percocet (Pfizer, New York, NY) consumption in the postoperative period (P = not significant). Further, self-reported postoperative pain did not differ significantly between groups at any of the time points (P = not significant). There were also no group differences with regard to any postoperative clinical recovery parameters.
Benzodiazepines administered before surgery have minimal beneficial effects on the postoperative clinical course of women undergoing abdominal hysterectomy.
Anesthesiology 04/2001; 94(3):415-22. · 5.36 Impact Factor
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ABSTRACT: Acupuncture can be an effective treatment for chronic anxiety disorders. The purpose of this study was to assess the effectiveness of acupuncture in reducing anxiety in a volunteer population. If found effective, this modality could be introduced as a treatment of anxiety before surgery. Adult volunteers (n = 55), were randomized to three treatment groups: a) Shenmen group--bilateral auricular acupuncture at the "shenmen" point; b) Relaxation group-bilateral auricular acupuncture at a "relaxation" point; and c) Sham group-bilateral auricular acupuncture at a "sham" point. Press-acupuncture needles were inserted at the respective auricular areas for 48 h. State anxiety, blood pressure, heart rate, and electrodermal activity were assessed at 30 min, 24 h, and 48 h after insertion. Analyzing anxiety levels using repeated-measures analysis of variance has demonstrated a significant difference [F (2,51) =8.8, P = 0.001] between the three treatment groups. Post hoc analysis demonstrated that patients in the Relaxation group were significantly less anxious at 30 min (P = 0.007) and 24 h (P = 0.035) as compared with patients in both the Shenmen group and the Sham group, and less anxious at 48 h (P = 0.042) as compared with patients in Shenmen group. Repeated-measures analysis of variance performed for electrodermal activity, blood pressure, and heart rate demonstrated no group differences (P = ns). We conclude that auricular acupuncture at the "relaxation" point can decrease the anxiety level in a population of healthy volunteers.
Anesthesia & Analgesia 03/2001; 92(2):548-53. · 3.29 Impact Factor
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ABSTRACT: To determine whether psychological variables such as preoperative anxiety can serve as predictors for the postoperative pain response.
The study sample included women who underwent elective abdominal hysterectomy (n=53). Two weeks prior to surgery, characteristics such as trait anxiety, coping style, and perceived stress were evaluated. Throughout the perioperative period, state anxiety, pain, as well as analgesic consumption were assessed at multiple time points. The anesthetic and surgical management were carefully controlled for and postoperative pain management was standardized.
Path analysis demonstrated that there are both direct and indirect effects of preoperative state anxiety on postoperative pain. Preoperative state anxiety is a significant positive predictor of the immediate postoperative pain (beta=0.30), which, in turn, is a positive predictor of pain on the wards (beta=0.54). Pain on the ward, in turn, is predictive for pain at home (beta=0.30).
The results of this study indicate that preoperative anxiety may have a critical role in the chain-of-events that controls the postoperative pain response.
Journal of Psychosomatic Research 01/2001; 49(6):417-22. · 3.30 Impact Factor
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ABSTRACT: To examine the relationship between social adaptability, cognitive abilities, and other personality characteristics to perioperative anxiety.
Prospective cohort investigation.
60 children ASA physical status I and II, age 3 to 10 years.
Tertiary care children's hospital.
Temperament (EASI), cognitive abilities (KABC), and adaptive behavior (Vineland) were evaluated in a group of children undergoing surgery. Parental coping style (MBBS) and parental state (STAI-S) and trait (STAI-T) anxiety were assessed as well. On the day of surgery, anxiety of the child was measured at the preoperative holding area and during induction of anesthesia (m-YPAS).
Univariate correlational analysis demonstrated that young age (r = -0.27), poor social adaptability (Vineland) (r = -0.38), shy and inhibited personality (EASI; temperament) (r = -0.33), higher intelligence (KABC) (r = 0.29), increased parental anxiety (r = 0.44), and parental high-monitoring coping style (r = -0.25) are all associated with higher levels of perioperative anxiety. Stepwise multivariate regression analysis has demonstrated that controlling for the variables above, parental anxiety (p = 0.004), child's social adaptive capabilities (p = 0.04), and child's temperament (sociability) (p = 0.04) are independent predictors for increased perioperative anxiety (R(2) = 0.38, F = 5.5, p = 0.003).
Anesthesiologists need to pay close attention to the families of pediatric surgical children who are socially maladjusted, shy and inhibited, and have anxious parents.
Journal of Clinical Anesthesia 12/2000; 12(7):549-54. · 1.21 Impact Factor
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ABSTRACT: The minimum time interval between administration of oral midazolam and separation of children from their parents that ensures good anterograde amnesia has not been previously determined. This is of particular importance in a busy operating room setting where schedule delays secondary to midazolam administration may not be tolerated.
Children (n = 113) undergoing general anesthesia and surgery completed preoperative baseline memory testing using a validated series of picture cards and were randomly assigned to one of three midazolam groups or a control group. Exactly, 5, 10, or 20 min after receiving oral midazolam (0.5 mg/kg) or 15 min after receiving placebo, children were administered a second memory test that used pictures. Anxiety of children was assessed during induction of anesthesia with use of a validated anxiety measurement tool. Postoperatively, recall and recognition for picture cards seen during baseline testing and postintervention testing were assessed.
Postoperatively, recall and recognition of pictures presented to patients after drug administration (anterograde amnesia) showed significant group differences (P = 0.0001), with recall impaired in the 10- (P = 0.004) and 20-min groups (P = 0.0001). Similarly, recognition memory was impaired in the 5- (P = 0.0008), 10- (P = 0.0001) and 20-min (P = 0.0001) groups. Significant anxiolytic effects of midazolam were observed as early as 15 +/- 4 min after midazolam administration (P = 0.02).
Midazolam administered orally produces significant anterograde amnesia when given as early as 10 min before a surgical procedure.
Anesthesiology 10/2000; 93(3):676-84. · 5.36 Impact Factor
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ABSTRACT: Previously, effects of preoperative sedatives were assessed mainly with respect to preoperative outcomes such as anxiety and compliance. The purpose of this investigation was to evaluate the effects of preoperative sedatives on postoperative psychological and clinical recovery.
Patients undergoing general anesthesia and outpatient surgery were enrolled in a double-blind, randomized, placebo-controlled trial. Subjects (n = 55) were randomly assigned to receive either 5 mg intramuscular midazolam (n = 26) or a placebo injection (n = 29) at least 30 min before surgery. The anesthetic technique was controlled. Postoperative anxiety, pain, analgesic consumption, clinical recovery parameters, and global health (SF-36) were evaluated up to 1 month after surgery.
Surgery length did not differ significantly between the treatment and placebo groups (118 +/- 45 min vs 129 +/- 53 min; P = NS). Throughout the first postoperative week, subjects in the treatment group reported a greater reduction in postoperative pain compared with subjects in the placebo group (F1,50= 3.5; P = 0.035). Moreover, at 1 week, ibuprofen use was reported by less subjects in the treatment group than in the placebo group (0% vs 17.2%; P = 0.026). Subjects in the treatment group also reported a greater reduction in postoperative anxiety throughout the follow-up period (F1,53 = 9.2; P = 0.04). However, global health indexes (SF-36) did not detect any significant differences between the two experimental groups (multivariate F1,45 = 0.44; P = 0.51).
Subjects treated with midazolam preoperatively self-report improved postoperative psychological and pain recovery. However, the clinical significance of these findings is unclear at the present time.
Anesthesiology 08/2000; 93(1):141-7. · 5.36 Impact Factor
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ABSTRACT: Although some anesthesiologists use oral sedatives or parental presence during induction of anesthesia (PPIA) to treat preoperative anxiety in children, others may use these interventions simultaneously (e.g., sedatives and PPIA). The purpose of this investigation was to determine whether this approach has advantages over treating children with sedatives alone.
The child's and the parental anxiety throughout the perioperative period was the primary endpoint of the study. Parental satisfaction was the secondary endpoint. Subjects (n = 103) were assigned randomly to one of two groups: a sedative group (0.5 mg/kg oral midazolam) or a sedative and PPIA group. Using standardized measures of anxiety and satisfaction, the effects of the interventions on the children and parents were assessed. Statistical analysis (varimax rotation) of the satisfaction questionnaire items resulted in two factors that described satisfaction of the separation process and satisfaction of the overall care provided.
Anxiety in the holding area, at entrance to the operating room, and at introduction of the anesthesia mask did not differ significantly between the two groups (F[2,192] = 1.26, P = 0.28). Parental anxiety after separation, however, was significantly lower in the sedative and PPIA group (F[2,93] = 4.46, P = 0.037). Parental satisfaction with the overall care provided (-0.28 +/- 1.2 vs. 0.43 +/- 0.26, P = 0.046) and with the separation process (-0.30 +/- 1.2 vs. 0.47 +/- 0.20, P = 0.03) was significantly higher among the sedative and PPIA group compared with the sedative group.
PPIA in addition to 0.5 mg/kg oral midazolam has no additive effects in terms of reducing a child's anxiety. Parents who accompanied their children to the operating room, however, were less anxious and more satisfied.
Anesthesiology 05/2000; 92(4):939-46. · 5.36 Impact Factor
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ABSTRACT: We performed a cross-sectional study to explore a potential association between preoperative anxiety and postoperative nausea and vomiting (PONV). The study enrolled 51 unpremedicated children 5-16 yr old undergoing outpatient surgery and standardized general anesthesia. Anxiety of children was assessed in the preoperative holding area and during the induction of anesthesia. The incidence of nausea and vomiting was documented in the postanesthesia care unit (PACU) and 24 h postoperatively (POD#1). In addition to univariate analysis, we used multivariate logistic regression models, wherein the dependent variable was the presence or absence of PONV and the independent variables included potential confounders such as age, sex, and perioperative opioid consumption. Univariate analysis showed that children who experienced nausea (32 +/- 5 vs 31 +/- 4, P = ns) or vomiting (32 +/- 4 vs 32 +/- 5, P = ns) in the PACU did not differ significantly in their anxiety before surgery. A multivariate model, in which the dependent variable was the presence or absence of vomiting at POD#1 and the independent variables included preoperative anxiety, age, sex, and opioid consumption, indicated that preoperative anxiety does not predict the occurrence of nausea and vomiting (P = ns). We conclude that children's anxiety in the preoperative holding area has no predictive value for the occurrence of PONV in the PACU or POD#1. IMPLICATIONS: This study was performed to explore a possible association between children's anxiety before surgery and postoperative nausea and vomiting. We found that controlling for confounding variables, anxiety in the preoperative holding area has no predictive value for the occurrence of postoperative nausea and vomiting.
Anesthesia & Analgesia 04/2000; 90(3):571-5. · 3.29 Impact Factor
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Z N Kain
Acta anaesthesiologica Belgica 02/2000; 51(4):217-26.
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ABSTRACT: The purpose of this study was to determine whether larger doses of anesthetics are required in the anxious patient to establish and maintain a clinically sufficient hypnotic component of the anesthetic state. Fifty-seven women undergoing bilateral laparoscopic tubal ligation with a propofol-based anesthetic regimen were enrolled in this cross-sectional study. Trait (baseline) and state (situational) anxiety were assessed in all patients immediately before surgery, and the propofol doses required for the induction and maintenance of anesthesia were recorded. A bispectral index monitor was used to assure that the hypnotic component of the anesthetic state was the same in all patients. We found that patients with high trait anxiety required more propofol for both the induction (2.1+/-0.4 vs 1.8+/-0.3 mg/kg; P = 0.01) and maintenance of anesthesia (170+/-70 vs 110+/-20 microg x kg(-1) x min(-1); P = 0.02), compared with patients with low trait anxiety. State anxiety, however, was not found to affect the propofol doses required for the induction or maintenance of anesthesia. Multiple regression models confirmed that Trait anxiety is an independent predictor for intraoperative propofol requirements (P = 0.02). We conclude that increased baseline (i.e., trait) anxiety is associated with increased intraoperative anesthetic requirements. Thus, we suggest that the initial dose of anesthetic administered by an anesthesiologist should be modified based on the anxiety level exhibited by the patient. IMPLICATIONS: The goal of this study was to assess the relationship between preoperative anxiety and intraoperative anesthetic requirements. We found that high baseline anxiety predicts increased intraoperative anesthetic requirements. We suggest that anesthesiologists should modify the initial induction dose based on the anxiety level exhibited by the patient.
Anesthesia & Analgesia 01/2000; 89(6):1346-51. · 3.29 Impact Factor
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ABSTRACT: To examine whether the establishment of dedicated pediatric operating rooms (ORs) staffed exclusively by pediatric anesthesiologists has had a significant impact on anesthetic efficiency during surgery.
Before and after design.
General and pediatric operating rooms at Yale-New Haven Hospital.
Using Operating Room Information System data (1991 to 1997), we examined whether the anesthesia-controlled time, the time it takes for induction and emergence of anesthesia of a selected surgical procedure (tonsillectomy and adenoidectomy), was affected by the change of practice from general to pediatric ORs. The average length of anesthesia induction decreased by 30% (p = 0.0007). Similarly, the average length of emergence from anesthesia decreased by 42% (p = 0.01) and anesthesia-controlled time decreased by 31% (p = 0.0008). Of particular importance is the decrease by 75% in the anesthesia-controlled time range (maximum-minimum).
The establishment of dedicated pediatric ORs resulted in significantly shorter anesthesia induction and emergence times. Furthermore, the decreased variability of anesthesia-controlled time may allow for better scheduling of surgical cases and for better surgeon and patient satisfaction.
Journal of Clinical Anesthesia 12/1999; 11(7):540-4. · 1.21 Impact Factor
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ABSTRACT: The human response to surgical stress is characterized by massive release of neuroendocrine hormones, provoking catabolism, thermogenesis, and hyperglycemia. Considering the possible adverse outcomes of excessive stress hormones, understanding various components of the stress response may improve management of postoperative morbidity. Leptin, initially described as an adipocyte-derived signaling factor, may also play an important role in regulating the hypothalamo-pituitary-adrenocortical axis. In phase I, plasma leptin and cortisol were measured in women before, during, and after total abdominal hysterectomy. The anesthetic technique was strictly controlled, balanced anesthesia. In phase II, plasma leptin and cortisol levels were measured in cardiac surgery patients. These subjects were anesthetized with a high dose opioid technique that blunts the intraoperative surgical stress response. In phase I, mean leptin levels did not change over the week before surgery, had a maximal decrease to 49% of baseline 2 h after surgery, and increased to just above baseline 24 h postoperatively. Cortisol was 176% of the baseline just before surgery, peaked at 2 h after surgery (383%), and remained elevated 24 h (200%) and 48 h (165%) after surgery. During the first 2 h of surgery, the decrease in leptin parallels the increase in cortisol. In phase II, high dose fentanyl limited both the cortisol increase and the leptin decrease; thus, the ratio of cortisol increase to leptin decrease was similar for the cardiac patients and the hysterectomy patients. These data indicate that leptin has a role in the surgically induced acute stress response in humans. Early in surgery the decrease in leptin parallels the increase in cortisol. This suggests a possible relationship between the neurobiology of these two systems, which could have important implications for regulation of the neuroendocrine response to surgical stress.
Journal of Clinical Endocrinology & Metabolism 08/1999; 84(7):2438-42. · 6.50 Impact Factor
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ABSTRACT: To evaluate whether isopropyl alcohol vapor is an effective treatment for postoperative nausea and vomiting.
Double-blind, randomized, controlled study.
Pediatric surgery center.
91 ASA physical status I and II children age 6-16 years, scheduled to undergo general anesthesia and elective outpatient surgery.
Subjects were randomized to inhale isopropyl alcohol or saline. The intervention was repeated up to three times. If postoperative nausea or vomiting persisted after three sequences, intravenous ondansetron was administered as rescue therapy.
Improvement in nausea was assessed using a visual analog scale, and improvement in vomiting was assessed using categorical analysis. After three treatment sequences, 65% of the children in the treatment group and 26% of the children in the control group had a significant reduction in the severity of either nausea or vomiting (p = 0.03). However, 54% of subjects in the treatment group and 80% of subjects in the control group had recurrent nausea or vomiting within 20 to 60 minutes.
Under the conditions of this study, repetitive inhaled isopropyl alcohol only achieved a transient antiemetic effect in children with established postoperative nausea or vomiting following general anesthesia and surgery.
Journal of Clinical Anesthesia 06/1999; 11(3):231-4. · 1.21 Impact Factor
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ABSTRACT: To examine the effect of perfusion on accuracy of two pulse oximeters in children and to determine thresholds of perfusion below which these pulse oximeters become inaccurate or cease to function.
Prospective, observational clinical study.
Operating room of a large university hospital.
19 children 10 years of age or less, who were scheduled for general anesthesia with placement of an intraarterial catheter.
A radial artery catheter, laser Doppler probe, skin temperature sensor, and band probes of two oximeters, Ohmeda 3700 (Boulder, CO) and Nellcor N200 (Hayward, CA), were attached to the same hand. Baseline pulse oximeter and Doppler readings were obtained with simultaneous hemoximetry (AVL Model 912 CO-Oxylite, Roswell, GA), skin and esophageal temperatures, total hemoglobin, and transduced arterial pressure. Readings of all parameters (n = 94) were obtained during periods of low perfusion or by occluding the upper arm to 70% to 100% of systolic pressure.
Bias (SpO2-SaO2) of each oximeter is compared to each perfusion variable (age, weight, core and skin temperature, hemoglobin concentration, pulse pressure, and percent flow by laser Doppler) to determine effect on accuracy. Data were analyzed using backward multivariate linear regression, Pearson correlation coefficients, and independent paired t-test. p < 0.05 was considered significant. Less than 2% bias is seen with either oximeter (Nellcor 1.55 +/- 2.33, Ohmeda 0.78 +/- 2.25). Independent predictors of bias for each machine include weight (r = -0.376; p < 0.001) and pulse pressure (r = 0.250; p = 0.021) for the Nellcor, and weight (r = -0.390; p < 0.001), percent flow by Doppler (r = 0.220; p = 0.035), and core temperature (r = 0.307; p = 0.003) for the Ohmeda. However, using predetermined thresholds for each variable, only skin temperature below 30 degrees C is identified as a significant predictor of oximeter inaccuracy.
At the parameters explored in this study, the selected seven perfusion variables (age, weight, core and skin temperature, hemoglobin concentration, pulse pressure, and percent flow by laser Doppler) have little effect on accuracy of pulse oximetry in children.
Journal of Clinical Anesthesia 06/1999; 11(4):317-22. · 1.21 Impact Factor
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ABSTRACT: Although multiple studies document the effect of sedative premedication on preoperative anxiety in children, there is a paucity of data regarding its effect on postoperative behavioral outcomes.
After screening for recent stressful life events, children undergoing anesthesia and surgery were assigned randomly to receive either 0.5 mg/kg midazolam in 15 mg/kg acetaminophen orally (n = 43) or 15 mg/kg acetaminophen orally (n = 43). Using validated measures of anxiety, children were evaluated before and after administration of the intervention and during induction of anesthesia. On postoperative days 1, 2, 3, 7, and 14, the behavioral recovery of the children was assessed using the Post Hospitalization Behavior Questionnaire.
The intervention group demonstrated significantly lower anxiety levels compared with the placebo group on separation to the operating room and during induction of anesthesia (F[1,77] = 3.95, P = 0.041). Using a multivariate logistic regression model, the authors found that the presence or absence of postoperative behavioral changes was dependent on the group assignment (R = 0.18, P = 0.0001) and days after operation (R = -0.20, P = 0.0001). Post hoc analysis demonstrated that during postoperative days 1-7, a significantly smaller number of children in the midazolam group manifested negative behavioral changes. At week 2 postoperatively, however, there were no significant differences between the midazolam and placebo groups.
Children who are premedicated with midazolam before surgery have fewer negative behavioral changes during the first postoperative week.
Anesthesiology 04/1999; 90(3):758-65. · 5.36 Impact Factor
