Christian C Apfel

University of Kentucky, Lexington, Kentucky, United States

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Publications (135)383.12 Total impact

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    ABSTRACT: Purpose The purpose of this study is to determine patient management strategies and outcomes for self-care of postdischarge nausea and vomiting (PDNV). Design Prospective, comparative, descriptive, and longitudinal study. Methods The sample consisted of 248 patients aged 18 years or older undergoing a procedure requiring general anesthesia. Patients recorded incidence and severity of nausea and vomiting, the impact of symptoms, and actions taken to alleviate symptoms for 7 days postdischarge. Findings The prevalence of PDNV was 56.9%. The methods used to relieve symptoms included antiemetic use by a minority and nonpharmacologic techniques of self-management by some. The effect of nausea on QOL, patient functioning, and patient satisfaction was significantly worse for those who experienced postdischarge nausea on all days. Conclusion Patients with PDNV use minor self-care strategies to manage symptoms. The presence of PDNV affects overall quality of life, patient functioning, and patient satisfaction.
    Journal of PeriAnesthesia Nursing. 08/2014; 29(4):275–284.
  • Christian C Apfel
    Pain 02/2014; · 5.64 Impact Factor
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    ABSTRACT: Intravenous (IV) acetaminophen has been shown to reduce postoperative pain and opioid consumption, which may lead to increased patient satisfaction. To determine the effect IV acetaminophen has on patient satisfaction, a pooled analysis from methodologically homogenous studies was conducted. We obtained patient-level data from five randomized, placebo-controlled studies in adults undergoing elective surgery in which patient satisfaction was measured using a 4-point categorical rating scale. The primary endpoint was "excellent" satisfaction and the secondary endpoint was "good" or "excellent" satisfaction at 24 hr after first study drug administration. Bivariate analyses were conducted using the chi-square test and Student's t-test and multivariable analyses were conducted using logistic regression analysis. Patients receiving IV acetaminophen were more than twice as likely as those who received placebo to report "excellent" patient satisfaction ratings (32.3% vs. 15.9%, respectively). Of all variables that remained statistically significant in the multivariable analysis (i.e., type of surgery, duration of anesthesia, last pain rating, and opioid consumption), IV acetaminophen had the strongest positive effect on "excellent" patient satisfaction with an odds ratio of 2.76 (95% CI 1.81-4.23). Results for "excellent" or "good" satisfaction were similar. When given as part of a perioperative analgesic regimen, IV acetaminophen was associated with significantly improved patient satisfaction.
    Journal for Healthcare Quality 01/2014;
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    ABSTRACT: The present guidelines are the most recent data on postoperative nausea and vomiting (PONV) and an update on the 2 previous sets of guidelines published in 2003 and 2007. These guidelines were compiled by a multidisciplinary international panel of individuals with interest and expertise in PONV under the auspices of the Society for Ambulatory Anesthesia. The panel members critically and systematically evaluated the current medical literature on PONV to provide an evidence-based reference tool for the management of adults and children who are undergoing surgery and are at increased risk for PONV. These guidelines identify patients at risk for PONV in adults and children; recommend approaches for reducing baseline risks for PONV; identify the most effective antiemetic single therapy and combination therapy regimens for PONV prophylaxis, including nonpharmacologic approaches; recommend strategies for treatment of PONV when it occurs; provide an algorithm for the management of individuals at increased risk for PONV as well as steps to ensure PONV prevention and treatment are implemented in the clinical setting.
    Anesthesia and analgesia 01/2014; 118(1):85-113. · 3.08 Impact Factor
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    ABSTRACT: Tissue oxygenation is a strong predictor of surgical site infection (SSI). Mild intraoperative hypercapnia increases peripheral, gastrointestinal, and splanchnic tissue oxygenation and perfusion. Hypercapnia also has anti-inflammatory effects. However, it is unknown whether hypercapnia reduces SSI risk. We tested the hypothesis that mild intraoperative hypercapnia reduces the risk of SSI in patients having colon resection surgery. METHODS: With institutional review board approval and subject consent, patients having elective colon resection (e.g. hemicolectomy and low-anterior resection) expected to last >2 h were randomly assigned to intraoperative normocapnia (PE'CO2 ≈ 35 mm Hg; n=623) or hypercapnia ( PE'CO2 ≈ 50 mm Hg; n=592). Investigators blinded to group assignment evaluated perioperative SSI (Center for Disease Control criteria) for 30 postoperative days. SSI rates were compared. RESULTS: Patient and surgical characteristics were comparable among the groups. The SSI rate for normocapnia was 13.3%, and for hypercapnia, it was 11.2% (P=0.29). The Executive Committee stopped the trial after the first a priori determined statistical assessment point because of much smaller actual effect compared with the projected. However, because the actual difference found in the SSI rates (15-16%) were within the 95% confidence intervals (CIs) of the projected relative difference of 33% (95% CI -43 to +24%), our results cannot be considered as 'no difference', and cannot exclude a Type II error. Time to first bowel movement was half-a-day shorter in the hypercapnia group. CONCLUSIONS: Mild hypercapnia appears to have little or-possibly-no ability to prevent SSI after colon resection. Other strategies for reducing SSI risk should thus take priority.
    BJA British Journal of Anaesthesia 11/2013; · 4.24 Impact Factor
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    ABSTRACT: 1) To quantify the incidence and severity of postdischarge nausea and vomiting (PDNV) for 7 days in adults undergoing outpatient surgeries with general anesthesia; 2) to evaluate whether a risk model previously developed for the first two postoperative days may be used to predict the patient's risk of PDNV for 7 days; and 3) to verify whether the same risk factors are applicable in the 3 t- 7 day period. Prospective two-site study of 248 patients. Multicenter study. 248 adult (>18 years) surgical outpatients undergoing ambulatory surgical procedures with general anesthesia between 2007 and 2008. The incidence and severity of PDNV and a simplified risk score for PDNV was assessed prospectively from discharge up to seven 7 postoperative days. The overall incidence of nausea was 56.9% and of emesis was 19.4%. The incidence of PDNV was highest on the day of surgery (DOS), with PDNV of 44.8% and decreased over time to 6.0% on day 7. Using the simplified risk score for PDNV the area under the receiver operating characteristic (ROC) curve was 0.766 (0.707, 0.825). A previous history of postoperative nausea and vomiting (PONV; OR 3.51, CI 1.70 - 7.27), operating room (OR) time (OR 2.19, 95% CI 1.34 - 3.60), use of ondansetron in the Postanesthesia Care Unit (PACU; OR 6.39, CI 1.65-24.79), and pain during days 3-7 (OR 1.67, CI 1.30 - 2.14) were the strongest predictors of PDNV on days 3-7. PDNV affects a significant number of patients after ambulatory surgery, and our simplified PDNV score may be applied adequately to a 7-day population. Pain appears to be a factor in late PDNV. It is possible that the presence of PDNV during days 3-7 has different origins than the PDNV that resolved over the first 48 hours.
    Journal of clinical anesthesia 08/2013; · 1.32 Impact Factor
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    Article: In reply.
    Anesthesiology 05/2013; 118(5):1229-30. · 5.16 Impact Factor
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    ABSTRACT: Real-time measurement of propofol in the breath may be used for routine clinical monitoring. However, this requires unequivocal identification of the expiratory phase of the respiratory propofol signal as only expiratory propofol reflects propofol blood concentrations. Determination of CO2 breath concentrations is the current gold standard for the identification of expiratory gas but usually requires additional equipment. Human breath also contains isoprene, a volatile organic compound with low inspiratory breath concentration and an expiratory concentration plateau. We investigated whether breath isoprene could be used similarly to CO2 to identify the expiratory fraction of the propofol breath signal. We investigated real-time breath data obtained from 40 study subjects during routine anesthesia. Propofol, isoprene, and CO2 breath concentrations were determined by a combined ion molecule reaction/electron impact mass spectrometry system. The expiratory propofol signal was identified according to breath CO2 and isoprene concentrations and presented as median of intervals of 30 s duration. Bland-Altman analysis was applied to detect differences (bias) in the expiratory propofol signal extracted by the two identification methods. We investigated propofol signals in a total of 3,590 observation intervals of 30 s duration in the 40 study subjects. In 51.4 % of the intervals (1,844/3,590) both methods extracted the same results for expiratory propofol signal. Overall bias between the two data extraction methods was -0.12 ppb. The lower and the upper limits of the 95 % CI were -0.69 and 0.45 ppb. Determination of isoprene breath concentrations allows the identification of the expiratory propofol signal during real-time breath monitoring.
    International Journal of Clinical Monitoring and Computing 03/2013;
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    ABSTRACT: Opioids are a key risk factor for postoperative nausea and vomiting (PONV). As intravenous (i.v.) acetaminophen reduces postoperative pain and opioid requirements, one would expect i.v. acetaminophen to be associated with a lower incidence of opioid-induced side effects, including PONV. We conducted a systematic search using Medline and Cochrane databases supplemented with hand search of abstract proceedings to identify randomized-controlled trials of i.v. acetaminophen. Inclusion criteria were (a) randomized for i.v. acetaminophen vs a placebo control, (b) general anesthesia, and (c) reported or obtainable PONV outcomes. Primary outcome was postoperative nausea and secondary outcome was postoperative vomiting. We included 30 studies with 2364 patients (1223 in the acetaminophen group, 1141 in the placebo group). The relative risk (95% confidence interval) was 0.73 (0.60-0.88) for nausea and 0.63 (0.45-0.88) for vomiting. Data showed significant heterogeneity for both nausea (P=0.02, I(2)=38%) and vomiting (P=0.006, I(2)=47%), but were homogeneous when studies were grouped according to timing of first administration: i.v. acetaminophen reduced nausea when given prophylactically either before surgery, 0.54 (0.40-0.74), or before arrival in the postanesthesia care unit, 0.67 (0.55-0.83); but not when given after the onset of pain, 1.12 (0.85-1.48). When i.v. acetaminophen was given prophylactically, the reduction of nausea correlated with the reduction of pain (odds ratio 0.66, 0.47-0.93), but not with reduction in postoperative opioids (odds ratio 0.89, 0.64-1.22). Prophylactically administered i.v. acetaminophen reduced PONV, mainly mediated through superior pain control.
    Pain 01/2013; · 5.64 Impact Factor
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    ABSTRACT: Human breath contains an abundance of volatile organic compounds (VOCs). Analysis of breath VOC may be used for diagnosis of various diseases or for on-line monitoring in anesthesia and intensive care. However, VOC concentrations largely depend on the breath sampling method and have a large inter-individual variability. For the development of breath tests, the influence of breath sampling methods and study subject characteristics on VOC concentrations has to be known. Therefore, we investigated the VOC isoprene in 62 study subjects during anesthesia and 16 spontaneously breathing healthy volunteers to determine (a) the influence of artificial and spontaneous ventilation and (b) the influence of study subject characteristics on breath isoprene concentrations. We used ion molecule reaction mass spectrometry for high-resolution breath-by-breath analysis of isoprene. We found that persons during anesthesia had significantly increased inspiratory and end-expiratory isoprene breath concentrations. Measured isoprene concentrations (median [first quartile-third quartile]) were in the anesthesia group: 54 [40-79] ppb (inspiratory) and 224 [171-309] ppb (end-expiratory), volunteer group: 14 [11-17] ppb (inspiratory) and 174 [124-202] ppb (end-expiratory). Higher end-tidal CO(2) concentrations in ventilated subjects were associated with higher expiratory isoprene levels. Furthermore, inspiratory and end-expiratory isoprene concentrations were correlated during anesthesia (r = 0.603, p < 0.001). Multivariate analysis showed that men had significantly higher end-expiratory isoprene concentrations than women. Rebreathing of isoprene from the anesthesia machine possibly accounts for the observed increase in isoprene in the anesthesia group.
    Journal of Breath Research 11/2012; 6(4):046004. · 2.57 Impact Factor
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    ABSTRACT: /st> In assessing a patient's risk for postoperative nausea and vomiting (PONV), it is important to know which risk factors are independent predictors, and which factors are not relevant for predicting PONV. /st> We conducted a systematic review of prospective studies (n>500 patients) that applied multivariate logistic regression analyses to identify independent predictors of PONV. Odds ratios (ORs) of individual studies were pooled to calculate a more accurate overall point estimate for each predictor. /st> We identified 22 studies (n=95 154). Female gender was the strongest patient-specific predictor (OR 2.57, 95% confidence interval 2.32-2.84), followed by the history of PONV/motion sickness (2.09, 1.90-2.29), non-smoking status (1.82, 1.68-1.98), history of motion sickness (1.77, 1.55-2.04), and age (0.88 per decade, 0.84-0.92). The use of volatile anaesthetics was the strongest anaesthesia-related predictor (1.82, 1.56-2.13), followed by the duration of anaesthesia (1.46 h(-1), 1.30-1.63), postoperative opioid use (1.39, 1.20-1.60), and nitrous oxide (1.45, 1.06-1.98). Evidence for the effect of type of surgery is conflicting as reference groups differed widely and funnel plots suggested significant publication bias. Evidence for other potential risk factors was insufficient (e.g. preoperative fasting) or negative (e.g. menstrual cycle). /st> The most reliable independent predictors of PONV were female gender, history of PONV or motion sickness, non-smoker, younger age, duration of anaesthesia with volatile anaesthetics, and postoperative opioids. There is no or insufficient evidence for a number of commonly held factors, such as preoperative fasting, menstrual cycle, and surgery type, and using these factors may be counterproductive in assessing a patient's risk for PONV.
    BJA British Journal of Anaesthesia 10/2012; 109(5):742-53. · 4.24 Impact Factor
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    ABSTRACT: Poorly controlled acute pain during the postoperative setting after abdominal surgery can be detrimental to the patient. Current pain management practices for the postoperative abdominal surgery patient rely heavily on opioids, which are associated with many unwanted side effects. Recently, interest surrounding regional anesthesia has been growing owing to its demonstrated efficacy and safety outcomes. More specifically, the transversus abdominis plane (TAP) block procedure has attracted attention owing to its ability to successfully block peripheral pain signaling in the abdomen, its ease of use, few complications, and its greater acceptability. A majority of the studies published has demonstrated the successful reduction in pain in many abdominal surgical procedures using local anesthetics during the TAP block. However, the short duration of the pain block causes the patient to still rely on other analgesics throughout the additional postoperative days. Preliminary studies using continuous infusion catheters placed in the TAP has been one of the ways to prolong the nerve block in the abdomen; however, technical and operational issues currently limit the widespread adoption of this method. In this review, current studies will be presented and summarized to update the field on the potential benefits of the TAP block procedure, in addition to providing insight into the future direction of the drugs that could be used for TAP block.
    Pain Practice 09/2012; · 2.61 Impact Factor
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    ABSTRACT: BACKGROUND:: Anincreasing number of elderly patients are treated for aneurysmal subarachnoid hemorrhage. Given that elderly age is associated with both poor outcome and an increased risk of hydrocephalus, we sought to investigate the interaction between age and hydrocephalus in outcome prediction. METHODS:: We enrolled 933 consecutive patients treated for subarachnoid hemorrhage between 2002 and 2010 and followed them for 1 yr after intensive care unit discharge. We first performed stepwise analyses to determine the relationship among neurologic events, elderly age (60 or more yr old), and 1-yr poor outcome (defined as Rankin 4-6). Within the most parsimonious model, we then tested for interaction between admission hydrocephalus and elderly age. Finally, we tested the association between age as a stratified variable and 1-yr poor outcome for each subgroup of patients with neurologic events. RESULTS:: 24.1% (n = 225) of subarachnoid hemorrhage patients were 60 yr old or more and 19.3% (n = 180) had 1-yr poor outcomes. In the most parsimonious model (area under the receiver operating characteristic curve, 0.84; 95% CI: 0.82 to 0.88; P < 0.001), elderly age and admission hydrocephalus were two independent predictors for 1-yr outcome (P < 0.001 and P = 0.004, respectively). Including the significant interaction between age and hydrocephalus (P = 0.04) improved the model's outcome prediction (P = 0.03), but elderly age was no longer a significant predictor. Finally, stratified age was associated with 1-yr poor outcome for hydrocephalus patients (P = 0.007), but not for patients without hydrocephalus (P = 0.87). CONCLUSION:: In this observational study, elderly age and admission hydrocephalus predicted poor outcome, but elderly age without hydrocephalus did not. An external validation, however, will be needed to generalize this finding.
    Anesthesiology 07/2012; · 5.16 Impact Factor
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    ABSTRACT: About one in four patients suffers from postoperative nausea and vomiting. Fortunately, risk scores have been developed to better manage this outcome in hospitalized patients, but there is currently no risk score for postdischarge nausea and vomiting (PDNV) in ambulatory surgical patients. We conducted a prospective multicenter study of 2,170 adults undergoing general anesthesia at ambulatory surgery centers in the United States from 2007 to 2008. PDNV was assessed from discharge until the end of the second postoperative day. Logistic regression analysis was applied to a development dataset and the area under the receiver operating characteristic curve was calculated in a validation dataset. The overall incidence of PDNV was 37%. Logistic regression analysis of the development dataset (n=1,913) identified five independent predictors (odds ratio; 95% CI): female gender (1.54; 1.22 to 1.94), age less than 50 yr (2.17; 1.75 to 2.69), history of nausea and/or vomiting after previous anesthesia (1.50; 1.19 to 1.88), opioid administration in the postanesthesia care unit (1.93; 1.53 to 2.43), and nausea in the postanesthesia care unit (3.14; 2.44-4.04). In the validation dataset (n=257), zero, one, two, three, four, and five of these factors were associated with a PDNV incidence of 7%, 20%, 28%, 53%, 60%, and 89%, respectively, and an area under the receiver operating characteristic curve of 0.72 (0.69 to 0.73). PDNV affects a substantial number of patients after ambulatory surgery. We developed and validated a simplified risk score to identify patients who would benefit from long-acting prophylactic antiemetics at discharge from the ambulatory care center.
    Anesthesiology 07/2012; 117(3):475-86. · 5.16 Impact Factor
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    ABSTRACT: Hypovolaemia after overnight fasting is believed to exacerbate postoperative nausea and vomiting (PONV). However, data on the efficacy of supplemental i.v. crystalloids for PONV prophylaxis are conflicting. We performed a literature search using CENTRAL, MEDLINE, EMBASE, CINAHL, and Web of Science. We included prospective randomized controlled trials that reported PONV event rates in patients receiving supplemental i.v. crystalloids or a conservative fluid regimen after elective surgery under general anaesthesia. Studies were evaluated with regard to random sequence generation, allocation concealment, blinding of participants, personnel, and outcome assessment, incomplete outcome data, and selective reporting. We identified 15 trials (n=787 crystalloids; n=783 conservative fluids). Compared with conservative fluids, i.v. crystalloids reduced the risk of early postoperative nausea (PON) (relative risk 0.73, 95% confidence interval 0.59-0.89; P=0.003), late PON (0.41, 0.22-0.76; P=0.004), and overall PON (0.66, 0.46-0.95; P=0.02). I.V. crystalloids did not reduce the risk of early postoperative vomiting (POV) (0.66, 0.37-1.16; P=0.16) or late POV (0.52, 0.25-1.11; P=0.09), but did reduce overall POV (0.48, 0.29-0.79; P=0.004). I.V. crystalloids did not reduce the risk of early PONV (0.74, 0.49-1.12; P=0.16), but did reduce the risk of late PONV (0.27, 0.13-0.54; P<0.001) and overall PONV (0.59, 0.42-0.84; P=0.003). I.V. crystalloids reduced the need for antiemetic rescue treatment (0.56, 0.45-0.68; P<0.001). In summary, supplemental i.v. crystalloids were associated with a lower incidence of several PONV outcomes. However, a number of PONV outcomes failed to reach statistical significance, perhaps due to the lack of power. Thus, studies sufficiently powered for the less frequent outcomes (e.g. POV) are required.
    BJA British Journal of Anaesthesia 06/2012; 108(6):893-902. · 4.24 Impact Factor
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    ABSTRACT: Buspirone, a partial 5HT(1A) agonist and D(2) and D(3) antagonist, has shown promising antiemetic efficacy when given parenterally in animal models, but its efficacy for the prevention of postoperative nausea and vomiting (PONV) is unknown. To study the efficacy and dose-responsiveness of intravenous buspirone for the prevention of PONV. A randomised, double-blind, placebo-controlled study was performed in adults at moderate to high PONV risk undergoing surgery with a general anaesthetic. Patients were randomised to receive an intravenous dose of buspirone (0.3, 1.0, 2.0, 3.0 mg) or placebo at the end of surgery. The primary endpoint was the cumulative 24-h PONV incidence (i.e. any nausea and/or vomiting). Vomiting included retching. Nausea was defined as a score of ≥4 on an 11-point verbal rating scale running from zero (no nausea) to ten (the worst nausea imaginable). A total of 257 patients received the study drug and fulfilled the criteria for inclusion in the primary efficacy and safety analyses. With placebo, the mean 24-h PONV incidence was 49.0 % (90 % confidence interval [CI] 37.5-60.5 %). With buspirone, that incidence ranged from a mean of 40.8 % (29.3-52.4 %) in the 1 mg arm to 58.0 % (46.5-69.5 %) in the 0.3 mg arm (P > 0.05 for all comparisons). There was no difference between placebo and buspirone at any dose for any other efficacy endpoint, nor in the number or severity of adverse events or any other safety measures. We were unable to show that intravenous single-dose buspirone, at the tested dose-range, was effective at preventing PONV in surgical adult patients. The present study emphasises the difficulty in extrapolating from animal models of emesis to clinical efficacy in PONV.
    European Journal of Clinical Pharmacology 05/2012; 68(11):1465-72. · 2.74 Impact Factor
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    ABSTRACT: Although partially controlled with antiemetic drugs, postoperative nausea and vomiting (PONV) continues to be a problem for many patients. Clinical research suggests that opioid analgesics and volatile anesthetics are the main triggers of PONV. The aim of this study was to develop an animal model for post-anesthesia vomiting for future studies to further determine mechanisms and preclinical drug efficacy. Ferrets (N=34) were initially used because they have served as a gold standard for emesis research. Ferrets were tested with several doses of morphine, inhaled isoflurane, and a positive control injection of cisplatin (a chemotherapy agent) to induce emesis. Musk shrews (a small animal model; N=36) were also tested for emesis with isoflurane exposure. A control injection of cisplatin produced emesis in ferrets (ip, 129.8±22.0 retches; 13.7±2.3 vomits; mean±SEM). Morphine also produced a dose-response on emesis in ferrets, with maximal responses at 0.9 mg/kg (sc, 29.6±12.6 retches; 1.8±0.9, vomits). Isoflurane exposure (2-4% for 10 min to 6h exposure) failed to induce vomiting, was not associated with an increased frequency in emesis when combined with a low dose of morphine (0.1 mg/kg, sc), and failed to produce consistent effects on food and water intake. In contrast to ferrets, musk shrews were very sensitive to isoflurane-induced emesis (0.5 to 3%, 10 min exposure; up to 11.8±2.4 emetic episodes). Overall, these results indicate that ferrets will not be useful for delineating mechanisms responsible for isoflurane-induced emesis; however, musk shrews may prove to be a model for vomiting after inhalation of volatile agents.
    Physiology & Behavior 04/2012; 106(4):562-8. · 3.16 Impact Factor
  • C C Apfel, S Jukar-Rao
    BJA British Journal of Anaesthesia 03/2012; 108(3):371-3. · 4.24 Impact Factor
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    ABSTRACT: Propofol in exhaled breath can be detected and monitored in real time by ion molecule reaction mass spectrometry (IMR-MS). In addition, propofol concentration in exhaled breath is tightly correlated with propofol concentration in plasma. Therefore, real-time monitoring of expiratory propofol could be useful for titrating intravenous anesthesia, but only if concentration changes in plasma can be determined in exhaled breath without significant delay. To evaluate the utility of IMR-MS during non-steady-state conditions, we measured the time course of both expiratory propofol concentration and the processed electroencephalography (EEG) as a surrogate outcome for propofol effect after an IV bolus induction of propofol. Twenty-one patients scheduled for routine surgery were observed after a bolus of 2.5 mg kg(-1) propofol for induction of anesthesia. Expiratory propofol was measured using IMR-MS and the cerebral propofol effect was estimated using the bispectral index (BIS). Primary endpoints were time to detection of expiratory propofol and time to onset of propofol's effect on BIS, and the secondary endpoint was time to peak effect (highest expiratory propofol or lowest BIS). Expiratory propofol and changes in BIS were first detected at 43 ± 21 and 49 ± 11 s after bolus injection, respectively (P = 0.29). Peak propofol concentrations (9.2 ± 2.4 parts-per-billion) and lowest BIS values (23 ± 4) were reached after 208 ± 57 and 219 ± 62 s, respectively (P = 0.57). Expiratory propofol concentrations measured by IMR-MS have similar times to detection and peak concentrations compared with propofol effect as measured by the processed EEG (BIS). This suggests that expiratory propofol concentrations may be useful for titrating intravenous anesthesia.
    Analytical and Bioanalytical Chemistry 02/2012; 403(2):555-61. · 3.66 Impact Factor
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    ABSTRACT: It is clear that patients with a severe traumatic brain injury (TBI) develop secondary, potentially lethal neurological deterioration. However, it is difficult to predict which patients with mild-to-moderate TBI (MM-TBI), even after intensive care unit (ICU) admission, will experience poor outcome at 6 months. Standard computed tomography (CT) imaging scans provide information that can be used to estimate specific gravity (eSG). We have previously demonstrated that higher eSG measurements in the standard CT reading were associated with poor outcomes after severe TBI. The aim of this study was to determine whether eSG of the intracranial content predicts 6-month outcome in MM-TBI. We analyzed admission clinical and CT scan data (including eSG) of 66 patients with MM-TBI subsequently admitted to our neurosurgical ICU. Primary outcome was defined as a Glasgow Outcome Scale score of 1 to 3 after 6 months. Discriminating power (area under the receiver operating characteristic curve [ROC-AUC], 95% confidence interval) of eSG to predict 6-month poor outcome was calculated. The correlation of eSG with the main ICU characteristics was then compared. Univariate and stepwise multivariate analyses showed an independent association between eSG and 6-month poor outcome (P = 0.001). ROC-AUC of eSG for the prediction of 6-month outcomes was 0.87 (confidence interval: 0.77-0.96). Admission eSG values were correlated with the main ICU characteristics, specifically 14-day mortality (P = 0.004), length of mechanical ventilation (P = 0.01), length of ICU stay (P = 0.045), and ICU procedures such as intracranial pressure monitoring (P < 0.001). In this MM-TBI cohort admitted to the ICU, eSG of routine CT scans was correlated with mortality, ICU severity, and predicted 6-month poor outcome. An external validation with studies that include the spectrum of TBI severities is warranted to confirm our results.
    Anesthesia and analgesia 02/2012; 114(5):1026-33. · 3.08 Impact Factor

Publication Stats

4k Citations
383.12 Total Impact Points


  • 2013
    • University of Kentucky
      • College of Nursing
      Lexington, Kentucky, United States
  • 2012–2013
    • Ludwig-Maximilian-University of Munich
      • Department of Anesthesiology
      München, Bavaria, Germany
    • Hôpital La Pitié Salpêtrière (Groupe Hospitalier "La Pitié Salpêtrière - Charles Foix")
      Lutetia Parisorum, Île-de-France, France
    • University Hospital München
      München, Bavaria, Germany
  • 2007–2013
    • University of California, San Francisco
      • Department of Anesthesia and Perioperative Care
      San Francisco, California, United States
    • Georgia Health Sciences University
      Augusta, Georgia, United States
    • Universität Mannheim
      Mannheim, Baden-Württemberg, Germany
  • 2010
    • Universitätsklinikum Dresden
      • Klinik und Poliklinik für Anästhesiologie und Intensivtherapie
      Dresden, Saxony, Germany
  • 2009
    • University of Texas MD Anderson Cancer Center
      Houston, Texas, United States
  • 2005–2009
    • Helsinki University Central Hospital
      Helsinki, Southern Finland Province, Finland
    • Universitätsklinikum Schleswig - Holstein
      • Klinik für Anästhesiologie und Operative Intensivmedizin (Kiel)
      Kiel, Schleswig-Holstein, Germany
  • 1998–2009
    • University of Wuerzburg
      • Department of Anaesthesia and Critical Care
      Würzburg, Bavaria, Germany
  • 2008
    • Kansas City VA Medical Center
      Kansas City, Missouri, United States
    • Tokyo Women's Medical University
      • Department of Anesthesiology
      Edo, Tōkyō, Japan
    • Trakya University
      • Department of Anaesthesiology
      Adrianoupolis, Edirne, Turkey
  • 2007–2008
    • CSU Mentor
      Long Beach, California, United States
  • 2004–2008
    • University of Louisville
      • Department of Anesthesiology
      Louisville, Kentucky, United States
    • Universität des Saarlandes
      • Klinik für Anästhesiologie, Intensivmedizin und Schmerztherapie
      Saarbrücken, Saarland, Germany
    • Institut Claudius Regaud
      Tolosa de Llenguadoc, Midi-Pyrénées, France
  • 2003
    • Heart & Vascular Outcomes Research Institute
      Beverly, Massachusetts, United States