Association between perioperative non-steroidal anti-inflammatory drug use and cardiovascular complications after non-cardiac surgery in older adult patients

BACKGROUND

We investigated in older adult non-cardiac surgical patients whether receipt of perioperative non-steroidal anti-inflammatory drugs (NSAIDs) is associated with increased incidence of postoperative cardiovascular complications.

METHODS

We retrospectively extracted the information for patients with age ≥  65 years who had inpatient non-cardiac surgery with a duration of ≥  1 h from the American College of Surgeons-National Surgical Quality Improvement Program registry data acquired at the University of Washington Medical Center. We compared patients who received NSAIDs perioperatively to those who did not receive NSAIDs, on the two composite outcomes: (1) the incidence of postoperative cardiovascular complications within 30 days of the surgery, and (2) the incidence of combined postoperative gastrointestinal and renal complications, and length of postoperative hospital stay. We used separate multivariable logistic regression models to analyze the two composite outcomes and a Poisson regression model for the length of hospital stay.

RESULTS

The receipt of perioperative NSAIDs was not associated with postoperative cardiovascular complications (estimated odds ratio (OR), 1.78; 95% confidence interval (CI), 0.97 to 3.25; P =  0.06), combined renal and gastrointestinal complications (estimated OR, 1.30; 95% CI, 0.53 to 3.20; P =  0.57), and length of postoperative hospital stay in days (incidence rate ratio, 1.06; 95% CI, 0.93 to 1.21; P =  0.39).

CONCLUSIONS

In older adult non-cardiac surgical patients, receipt of perioperative NSAIDs was not associated with increased incidences of postoperative cardiovascular complications, and renal and gastrointestinal complications within 30 days after surgery, or length of postoperative hospital stay.

Association Between Postoperative Methocarbamol and Postoperative Pain Opioid Dose Requirements: A Retrospective Cohort Study

OBJECTIVES

We tested the hypothesis that patients who received methocarbamol postoperatively experience less severe pain and require smaller doses of opioids than those who did not receive methocarbamol.

MATERIALS AND METHODS

This is a retrospective cohort study of patients undergoing surgery involving the musculoskeletal system. Of 9089 patients, 704 received methocarbamol during 48 hours postoperatively, while 8385 did not receive methocarbamol. The patients who received methocarbamol postoperatively and the patients who did not receive methocarbamol were compared on the time-weighted average (TWA) pain score and opioid dose requirements in morphine milligram equivalents (MME) during the first 48 hours postoperatively, using propensity score-weighted regression models to adjusting for preoperative and intraoperative covariates.

RESULTS

Postoperative 48-hour TWA pain scores were 5.5±1.7 (mean±SD), and 4.3±2.1 for methocarbamol and non-methocarbamol patients. Postoperative 48-hour opioid dose requirements in MME were 276 [170-347] (median [interquartile range (IQR)]) mg, and 190 [60-248] mg for methocarbamol and non-methocarbamol patients. In propensity score-weighted regression models, receiving methocarbamol postoperatively was associated with 0.97-point higher postoperative TWA pain score (95% CI, 0.83-1.11; P <0.001), and 93.6-MME higher postoperative opioid dose requirements (95% CI, 79.9 to 107.4; P <0.001), compared with not receiving methocarbamol postoperatively.

DISCUSSION

Postoperative methocarbamol was associated with significantly higher acute postoperative pain burden and opioid dose requirements. Although the results of the study are influenced by residual confounding, they suggest a limited-if any-benefit of methocarbamol as an adjunct of postoperative pain management.

Prediction of postoperative respiratory depression and respiratory complications in patients on preoperative methadone

PURPOSE

We developed prediction models for postoperative respiratory depression and respiratory complications for 958 patients who were on methadone preoperatively.

METHODS

The primary outcome was postoperative respiratory depression as defined by respiratory rate < 10/min, oxygen saturation (SpO₂) < 90%, or requirement of naloxone for 48 h postoperatively. Secondary outcome was the composite of postoperative respiratory complications. Prediction models for postoperative respiratory depression and respiratory complications were constructed using multivariate logistic regression with preoperative and intraoperative characteristics as the predictors.

RESULTS

For the multivariate logistic regression model for postoperative respiratory depression, surgery duration (P = 0.005), body mass index (BMI) (P = 0.008), surgery involving digestive system (P = 0.031), and American Society of Anesthesiologists (ASA) physical status ≥ 4 (P = 0.038) were statistically significant predictors. The area under the receiver operating characteristic curve (AUROC) of the model was 0.581 (0.558-0.601) [median (95% confidence interval (CI))] with fivefold cross-validation. For the model for postoperative respiratory complications, surgery duration (P = 0.001), history of hypertension (P = 0.028), surgery involving musculoskeletal system (P < 0.001), surgery involving integumental system (P = 0.034), surgery categorized to miscellaneous therapeutic procedures (P = 0.028), combined general and regional anesthesia (P = 0.033), ASA physical status 3 (P < 0.001), and ASA physical status ≥ 4 (P < 0.001) were statistically significant predictors, and AUROC of the model was 0.726 (0.712-0.737).

CONCLUSIONS

Multivariate logistic regression models including preoperative, and intraoperative characteristics as the predictors performed poorly to predict postoperative respiratory depression, and moderately for postoperative respiratory complications. Neither model is accurate enough to be subject to clinical use.

Postoperative respiratory depression in patients on sublingual buprenorphine: a retrospective cohort study for comparison between postoperative continuation and discontinuation of buprenorphine

Background

We tested the hypothesis that patients who continued buprenorphine postoperatively experience postoperative respiratory depression less frequently than those who discontinued buprenorphine.

Methods

This is a retrospective cohort study of patients who were on buprenorphine preoperatively. The primary outcome was postoperative respiratory depression as defined by respiratory rate < 10/minute, oxygen saturation (SpO₂) < 90%, or requirement of naloxone for 48 h postoperatively. The secondary outcome was the composite of postoperative respiratory complications. The associations between postoperative buprenorphine continuation and respiratory depression and respiratory complications were estimated using separate multivariable logistic regression models, including demographic, intraoperative characteristics, and preoperative buprenorphine dose as covariates.

Results

Postoperative buprenorphine continuation was not associated with postoperative respiratory depression (adjusted odds ratio (OR), 1.11, 95% confidence interval (CI), 0.61 to 1.99, P=0.72). In subanalysis stratified by the preoperative buprenorphine dose, buprenorphine continuation was not associated with postoperative respiratory depression either when preoperative buprenorphine dose was high (≥16 mg daily) or low (<16 mg daily). Postoperative buprenorphine continuation was associated with lower incidence of postoperative respiratory complications (adjusted OR, 0.43, 95% CI, 0.21 to 0.86, P=0.02).

Conclusions

Continuing buprenorphine was not associated with respiratory depression, but it was associated with a lower incidence of respiratory complications.

Supplementary Information

The online version contains supplementary material available at 10.1186/s40981-022-00535-2.

Patient Blood Management programs for post-partum hemorrhage

Patient blood management (PBM) strategies aim to maintain hemoglobin concentration, optimize hemostasis, and minimize blood loss to improve patient outcomes. Because postpartum hemorrhage (PPH) is a leading cause of maternal mortality and blood product utilization, PBM principles can be applied in its therapeutic approach. First, pre-operative identification of risk factors for PPH and identification of peri-delivery anemia should be conducted. Iron supplementation should be used to optimize hemoglobin concentration before delivery; it can also be used to treat anemia in the postpartum period after severe PPH. Both acute normovolemic hemodilution and intraoperative cell salvage can be effective techniques to reduce allogeneic blood transfusion during or after surgical procedures. Furthermore, these strategies appear to be safe when used in the pregnant population.

Spinal anesthesia for cesarean section in a woman with an intrathecal baclofen pump

BACKGROUND

Intrathecal baclofen pumps are commonly used for the management of lower extremity spasticity in the setting of spinal cord injury. There have been no reports of the performance of spinal anesthesia in patients with a pre-existing intrathecal baclofen pump.

CASE PRESENTATION

A 29-year-old parturient presented for cesarean section. She had a history of spinal cord injury due to fractures of the thoracic vertebrae with lower extremity spasticity, which had been treated with an intrathecal baclofen pump inserted through lumbar (L) 3-L4 intervertebral space. Preoperative lumbosacral ultrasound was performed to identify the L4-5 interspace, and spinal anesthesia was performed through that space with a 25-gauge 3.5-inch-long Whitacre spinal needle. Thoracic (T) 4 dermatomal level anesthesia was achieved, and the patient underwent the cesarean section without requiring additional intravenous analgesic adjuncts.

CONCLUSIONS

Spinal anesthesia can be successfully performed in patients with intrathecal baclofen pumps. Existing intrathecal catheters can be located with preoperative imaging, and ultrasound can be used to determine the vertebral levels below the intrathecal catheter through which spinal anesthesia can be performed safely.

In-Hospital Opioid Consumption After the Previous Cesarean Delivery Weakly Predicts Opioid Consumption After Index Delivery: A Retrospective Cohort Study

BACKGROUND

To predict opioid consumption and pain intensity after the index cesarean delivery, we tested a hypothesis that opioid consumption after the previous cesarean delivery of the same patient can predict the opioid consumption after the index cesarean delivery. We further tested a secondary hypothesis that the pain scores after the previous cesarean delivery can predict the pain scores after the index cesarean delivery.

METHODS

This is a retrospective cohort study of 470 women who underwent both previous and index cesarean deliveries at a single institution from January 2011 to June 2019. To predict the opioid consumption (primary outcome) and average pain scores (on 11-point numeric rating scale) after their index cesarean delivery, we used a linear regression model incorporating only the opioid consumption and average pain scores after the previous cesarean delivery, respectively (unadjusted models). Demographic and obstetric variables were then added as predictors (adjusted models). The bootstrap was used to compare these models with respect to proportion of variance of the outcome accounted for (R2).

RESULTS

Unadjusted models were weakly predictive of opioid consumption (R2 = 0.268; 95% confidence interval [CI], 0.146-0.368) and average pain scores (R2 = 0.176; 95% CI, 0.057-0.250). An adjusted model for opioid consumption was weakly predictive (R2 = 0.363; 95% CI, 0.208-0.478), but an adjusted model for average pain scores was not predictive of the outcomes (R2 = 0.070; 95% CI, -0.143 to 0.219). Adjusted models failed to explain variances of opioid consumption and average pain scores significantly better than unadjusted models (P = .099 and P = .141, respectively).

CONCLUSIONS

Opioid consumption and pain scores after women's previous cesarean delivery only explain 27% of variance of opioid consumption and 18% of variance of their pain after their index cesarean delivery. Therefore, previous cesarean delivery analgesic metrics are not robust enough to be used as clinically applicable predictors for index delivery.

Case Report: Radiographic Identification of Intrapleural Misplacement of Epidural Catheter in an Intubated Post-Lung Transplant Patient

Intrapleural misplacement of epidural catheter is a rare complication of thoracic epidural placement, which can be difficult to detect in intubated patients with unreliable pain reports and hemodynamic response to the test dose. We describe a case of intrapleural misplacement of thoracic epidural in a 50-year-old man status-post bilateral lung transplant and highlight the use of radiographic techniques to identify the misplacement.

Postoperative Pain and Opioid Dose Requirements in Patients on Sublingual Buprenorphine: A Retrospective Cohort Study for Comparison Between Postoperative Continuation and Discontinuation of Buprenorphine

OBJECTIVE

To test the hypothesis that patients who continued buprenorphine postoperatively experience less severe pain and require a smaller dose of opioids than those who discontinued buprenorphine.

MATERIALS AND METHODS

This is a retrospective cohort study of surgical patients who were on buprenorphine preoperatively. Using our previous study's data as pilot data, we selected the covariates to be included in 2 regression models with postoperative time-weighted average pain score and opioid dose requirements in morphine milligram equivalents during 48 hours after surgery as the outcomes. Both contained preoperative daily buprenorphine dose, whether buprenorphine was continued postoperatively, and the preoperative daily dose-by-postoperative continuation interaction as predictors. Precision variables were identified by exhaustive search of perioperative parameters with the exposure variables (preoperative daily dose, postoperative continuation, and their interaction) included in the regression model. The model selected by using the pilot data was estimated again using the new data extracted for this study to make inference about the effect of the 2 exposures (postoperative buprenorphine continuation and preoperative daily buprenorphine dose) and their interaction on the outcomes.

RESULTS

Continuing buprenorphine was associated with a 1.3-point lower time-weighted average pain score than discontinuing (95% confidence interval, 0.39-2.21; P=0.005) but was not associated with a difference in opioid dose requirements (P=0.48).

DISCUSSION

Continuing buprenorphine was associated with lower postoperative pain levels than discontinuing. Our results were primarily driven by patients on lower buprenorphine dose as only 22% of patients were on daily doses of 24 mg or above.

Intraoperative panic attack in patients undergoing awake craniotomy: a retrospective analysis of risk factors

PURPOSE

Intraoperative anxiety is the most common psychological response of the patient during awake craniotomy. Psychological stress can trigger patient decline, resulting in failed awake craniotomy and significantly poor outcomes. This study aimed to identify the risk factors for panic attack (PA) during awake craniotomies.

METHODS

With the local ethics committee approval, we conducted a manual chart review of the medical record of patients who underwent consecutive awake craniotomies between November 1999 and October 2016 at Tokyo Women's Medical University. A total of 405 patients were identified and assigned to 2 groups based on the Diagnostic and Statistical Manual of Mental Disorders-V criteria: those that met the PA criteria (Group PA) and those that did not (Group non-PA). Patient characteristics and the incidence of the PA specifier were collected. The features of the two groups were statistically compared, and risk factors for PA occurrence were determined by regression analysis.

RESULTS

Sixteen of 405 patients met the diagnostic criteria of PA. Patients' characteristics were not statistically different between the groups. Multivariate logistic regression showed that intraoperative anxiety (p = 0.0002) and age younger than 39 years (as opposed to age >  = 39 years; p = 0.0328) were significantly associated with the occurrence of PA during awake craniotomy.

CONCLUSIONS

For patients undergoing awake craniotomy, intraoperative anxiety and age younger than 39 years were considered risk factors of PA. As PA often necessitates conversion to general anesthesia, intensive perioperative psychological support and pain management are required to achieve patient satisfaction and the surgical goal of awake craniotomy.

Association Between Preoperative Statin Use and Respiratory Complications After Noncardiac Surgery: A Retrospective Cohort Analysis

BACKGROUND

Statins possess pleiotropic effects, which potentially benefit noncardiovascular conditions. Previous work suggests that statins reduce inflammation and prevent acute respiratory distress syndrome and infections. However, there is a paucity of data regarding potential benefits of statins on respiratory and infectious complications, particularly after noncardiac surgery. We therefore evaluated respiratory and other complications in noncardiac surgery patients taking or not taking statins preoperatively.

METHODS

We obtained data from the Cleveland Clinic Perioperative Health Documentation System and evaluated medical records of 92,139 inpatients who had noncardiac surgery. Among these, 31,719 patients took statins preoperatively. Statin patients were compared to nonstatin patients on incidence of intraoperative use of albuterol and postoperative respiratory complications for primary analysis. Infectious complications, cardiovascular complications, in-hospital mortality, and duration of hospitalization were compared for secondary analyses, using inverse probability of treatment weighting to control for potential confounding.

RESULTS

Statin use was associated with lower odds of intraoperative albuterol treatment (odds ratio [OR] = 0.89; 97.5% confidence interval [CI], 0.82-0.97; P = .001; number needed to treat [NNT] = 216). Postoperative respiratory complications were also less common (OR = 0.82; 98.75% CI, 0.78-0.87; P < .001). Secondarily, statin use was associated with lower odds of infections, cardiovascular complications, in-hospital mortality, and shorter duration of hospitalization. The interaction between statin use and sex was significant (with significance criteria P < .10) for all primary and secondary outcomes except intraoperative use of albuterol.

CONCLUSIONS

Preoperative statin use in noncardiac surgical patients was associated with slightly reduced odds of postoperative respiratory, infectious, and cardiovascular complications. However, the NNTs were high. Thus, despite the fact that statins appeared to be associated with lower odds of various complications, especially cardiovascular complications, our results do not support using statins specifically to reduce noncardiovascular complications after noncardiac surgery.

Factors associated with persistent pain after childbirth: a narrative review

A systematic literature search was performed to identify studies that reported risk factors for persistent pain after childbirth. Many studies have sought to identify risk factors for post-delivery pain in different populations, using different methodologies and different outcome variables. Studies of several different but interrelated post-partum pain syndromes have been conducted. Factors strongly and specifically associated with persistent incisional scar pain after Caesarean delivery include a coexisting persistent pain problem in another part of the body and severe acute postoperative pain. For persistent vaginal and perineal pain, operative vaginal delivery and the magnitude of perineal trauma have been consistently linked. History of pregnancy-related and pre-pregnancy back pain and heavier body weight are robust risk factors for persistent back pain after pregnancy. Unfortunately, limitations, particularly small samples and lack of a priori sample size calculation designed to detect specific effect sizes for risk of persistent pain outcomes, preclude definitive conclusions about many other predictors and the strength of outcome associations. In future studies, assessments of specific phenotypes using a rigorous analysis with appropriate predetermined sample sizes and validated instruments are needed to allow elucidation of stronger and reliable associations. Interventional studies targeting the most robustly associated, modifiable risk factors, such as acute post-partum pain, may lead to solutions for the prevention and treatment of these common problems that impact a large population.

Deciphering the influence of paraimmunobiotic bifidobacteria on the innate antiviral immune response of bovine intestinal epitheliocytes by transcriptomic analysis

Previously, we reported that the non-viable immunomodulatory Bifidobacterium infantis MCC12 and Bifidobacterium breve MCC1274 strains (paraimmunobiotic bifidobacteria) were able to increase the protection against rotavirus infection in bovine intestinal epithelial (BIE) cells. In order to gain insight into the influence of paraimmunobiotic bifidobacteria on the innate antiviral immune response of BIE cells, their effect on the transcriptomic response triggered by Toll-like receptor 3 (TLR3) activation was investigated. By using microarray technology and qPCR analysis, we obtained a global overview of the immune genes involved in the innate antiviral immune response in BIE cells. Activation of TLR3 by poly(I:C) in BIE cells significantly increased the expression of interferon (IFN)-α and IFN-β, several interferon-stimulated genes, cytokines, and chemokines. It was also observed that both paraimmunobiotic bifidobacteria differently modulated immune genes expression in poly(I:C)-challenged BIE cells. Most notable changes were found in genes involved in antiviral defence (IFN-β, MX1, OAS1X, MDA5, TLR3, STAT2, STAT3), cytokines (interleukin (IL)-6), and chemokines (CCL2, CXCL2, CXCL6) that were significantly increased in bifidobacteria-treated BIE cells. B. infantis MCC12 and B. breve MCC1274 showed quantitative and qualitative differences in their capacities to modulate the innate antiviral immune response in BIE cells. B. breve MCC1274 was more efficient than the MCC12 strain to improve the production of type I IFNs and antiviral factors, an effect that could be related to its higher ability to protect against rotavirus replication in BIE cells. Interestingly, B. infantis MCC12 showed a remarkable anti-inflammatory effect. The MCC12 strain was more efficient to reduce the expression of inflammatory cytokines and chemokines (IL-16, IL-20, CX3CL1) when compared with B. breve MCC1274. These results provided valuable information for the deeper understanding of the antiviral immune response of intestinal epithelial cells as well as the host-paraimmunobiotic interaction in the bovine host.

Ultrasound Quantification of Anterior Soft Tissue Thickness Fails to Predict Difficult Laryngoscopy in Obese Patients

Morbid obesity is associated with difficult laryngoscopy and intubation. In the general population, bedside indices for predicting difficult intubation (i.e. Mallampati classification, thyromental distance, sternomental distance, mouth-opening and Wilson risk score) have poor-to-moderate sensitivity (20-62%) and moderate-to-fair specificity (82-97%). In the obese population, although the risk of difficult intubation after a positive Mallampati test is 34%, it is still not sufficient to be used as a single predictive test. An abundance of pretracheal soft tissue anterior to the vocal cords, as quantified by ultrasound, was a better predictor of difficult laryngoscopy than body mass index (BMI) in Israeli patients. Obesity is a growing problem in the United States: therefore we sought to confirm this finding in the obese population in the United States. We used ultrasound to quantify the neck soft tissue, from the skin to the anterior aspect of the trachea at the vocal cords, in 64 obese patients (BMI >35). We assessed thyromental distance, mouth-opening, jaw movement, limited neck mobility, modified Mallampati score, abnormal upper teeth, neck circumference, confirmed obstructive sleep apnoea, BMI, age, race and gender as predictors. Twenty patients were classified as difficult laryngoscopy; they were older (47±9 vs 42±1 years; P=0.048; mean±SD) and had less soft pretracheal tissue (20.4±3.0 vs 22.3±3.8 mm; P=0.049) than did easy laryngoscopy patients. Multivariate regression indicated that none of the factors was an independent predictor of difficult laryngoscopy. We conclude that the thickness of pretracheal soft tissue at the level of the vocal cords is not a good predictor of difficult laryngoscopy in obese patients in the United States.

Prediction of outliers in pain, analgesia requirement, and recovery of function after childbirth: a prospective observational cohort study

BACKGROUND

Prediction models to identify parturients who experience protracted pain, prolonged opioid use, and delayed self-assessed functional recovery are currently inadequate.

METHODS

For this study, 213 nulliparous women who planned vaginal delivery were enrolled and assessed daily until they completed three outcomes: (1) pain resolution; (2) opioid cessation; and (3) self-assessed functional recovery to predelivery level. The primary composite endpoint, 'pain and opioid-free functional recovery' was the time required to reach all three endpoints. The subjects were divided into two categories (the worst (longest time) 20% and remaining 80%) for reaching the primary composite endpoint, and each individual component. Prediction models for prolonged recovery were constructed using multivariate logistic regression with demographic, obstetric, psychological, and health-related quality of life characteristics as candidate predictors.

RESULTS

Labour induction (vs spontaneous labour onset) predicted the worst 20% for the primary composite endpoint in the final multivariate model. Labour induction and higher postpartum day 1 numerical rating score for pain were predictors for being in the worst 20% for both functional recovery and pain burden. Labour type, delivery type, Patient-Reported Outcomes Measurement Information System (PROMIS) anxiety score, RAND 36 Item Health Survey 1.0 (SF-36) physical health composite score, and postpartum breastfeeding success were predictive of delayed opioid cessation.

CONCLUSIONS

Labour induction and elevated numerical rating score for pain are predictive of poor recovery after childbirth. Further research is necessary to determine whether modification would benefit mothers at risk for poor recovery.

Lactobacillus fermentum UCO-979C beneficially modulates the innate immune response triggered by Helicobacter pylori infection in vitro

Helicobacter pylori infection is associated with important gastric pathologies. An aggressive proinflammatory immune response is generated in the gastric tissue infected with H. pylori, resulting in gastritis and a series of morphological changes that increase the susceptibility to cancer development. Probiotics could present an alternative solution to prevent or decrease H. pylori infection. Among them, the use of immunomodulatory lactic acid bacteria represents a promising option to reduce the severity of chronic inflammatory-mediated tissue damage and to improve protective immunity against H. pylori. We previously isolated Lactobacillus fermentum UCO-979C from human gastric tissue and demonstrated its capacity to reduce adhesion of H. pylori to human gastric epithelial cells (AGS cells). In this work, the ability of L. fermentum UCO-979C to modulate immune response in AGS cells and PMA phorbol 12-myristate 13-acetate (PMA)-differentiated THP-1 (human monocytic leukaemia) macrophages in response to H. pylori infection was evaluated. We demonstrated that the UCO-979C strain is able to differentially modulate the cytokine response of gastric epithelial cells and macrophages after H. pylori infection. Of note, L. fermentum UCO-979C was able to significantly reduce the production of inflammatory cytokines and chemokines in AGS and THP-1 cells as well as increase the levels of immunoregulatory cytokines, indicating a remarkable anti-inflammatory effect. These findings strongly support the probiotic potential of L. fermentum UCO-979C and provide evidence of its beneficial effects against the inflammatory damage induced by H. pylori infection. Although our findings should be proven in appropriate experiments in vivo, in both H. pylori infection animal models and human trials, the results of the present work provide a scientific rationale for the use of L. fermentum UCO-979C to prevent or reduce H. pylori-induced gastric inflammation in humans.

Dissecting the structural basis for the intracellular delivery of OSW-1 by fluorescent probes

The structural basis for the intracellular delivery of OSW-1 is investigated using fluorescent derivatives of OSW-1 and its closely related congeners. Despite the large differences in activity, all the fluorescent probes are found to translocate across the plasma membrane to the ER and Golgi apparatus. This observation suggests that the glycosylated cholestane moiety plays an important role in the cell internalization and intracellular localization property of OSW-1.

Steroid administration after anaesthetic induction with etomidate does not reduce in-hospital mortality or cardiovascular morbidity after non-cardiac surgery

BACKGROUND

We tested the primary hypothesis that corticosteroid administration after etomidate exposure reduces a composite of in-hospital mortality and cardiovascular morbidity after non-cardiac surgery.

METHODS

We evaluated ASA physical status III and IV patients who had non-cardiac surgery with general anaesthesia at the Cleveland Clinic. Amongst 4275 patients in whom anaesthesia was induced with etomidate, 804 were also given steroid intraoperatively, mostly dexamethasone at a median dose of 6 mg. We successfully matched 582 steroid patients with 1023 non-steroid patients. The matched groups were compared on composite of in-hospital mortality and cardiovascular morbidity using a generalized-estimating-equation model. Secondly, the matched groups were compared on length of hospital stay using a Cox proportional hazard model, and were descriptively compared on intraoperative blood pressures using a standardized difference.

RESULTS

There was no significant association between intraoperative steroid administration after anaesthetic induction with etomidate and the composite of in-hospital mortality or cardiovascular morbidity; the estimated common odds ratio across the two components of the composite was 0.86 [95% confidence interval (CI): 0.64, 1.16] for steroid vs non-steroid, P=0.33. The duration of postoperative hospitalisation was significantly shorter amongst steroid patients [median (Q1, Q3): 6 (3, 10) days] than non-steroid patients [7 (4, 11) days], with an estimated hazard ratio of 0.89 (0.80, 0.98) for steroid vs non-steroid, P=0.01. Intraoperative blood pressures were similar in steroid and non-steroid patients.

CONCLUSIONS

Steroid administration after induction of anaesthesia with etomidate did not reduce mortality or cardiovascular morbidity.

Recovery after Nulliparous Birth: A Detailed Analysis of Pain Analgesia and Recovery of Function

BACKGROUND

The majority of parturients in the United States first return for evaluation by their obstetric practitioner 6 weeks after delivery. As such, there is little granular data on the pain experience, analgesic requirements, and functional recovery during the postpartum period. This prospective observational study was performed to evaluate these factors to provide expectations for patients.

METHODS

A total of 213 nulliparous women were enrolled and assessed daily until they completed 3 outcomes: (1) pain resolution; (2) opioid cessation; and (3) self-assessed functional recovery from delivery. The primary endpoint, pain- and opioid-free functional recovery, was the time required to reach all three of the endpoints. Pain burden was assessed as the area under the curve created by plotting the daily numerical pain rating scale against the days required to attain pain resolution. Times to attain study endpoints after cesarean delivery and vaginal delivery were compared using survival analysis.

RESULTS

After vaginal delivery, days required for pain and opioid-free functional recovery (median [interquartile range (IQR)]) were 19 [11 to 26], for opioid cessation 0 [0 to 2], termination of all analgesic (including nonsteroidal antiinflammatories and acetaminophen) 11 [5 to 17], and pain resolution 14 [7 to 24]. Achievement of these endpoints after cesarean delivery required 27 [19 to 40], 9 [5 to 12], 16 [11 to 24], and 21 [14 to 27] days, respectively.

CONCLUSIONS

There is clinically significant variability between healthy nulliparous parturients in the pain experience, opioid use, and functional recovery after childbirth following vaginal and cesarean delivery. Recovery to predelivery function is similar after vaginal and cesarean delivery, and approximately half of the variance was explained by pain burden.

Synthesis of a fluorescent photoaffinity probe of OSW-1 by site-selective acylation of an inactive congener and biological evaluation

A novel fluorescent photoaffinity probe of OSW-1 was prepared in two steps from a naturally occurring inactive congener by a sequential site-selective acylation strategy using Me₂SnCl₂. It displayed highly potent anticancer activity and a similar intracellular localization property to that of a fluorescently-tagged OSW-1, thereby demonstrating its potential utility in live cell studies.

Correction: Synthesis of a fluorescent photoaffinity probe of OSW-1 by site-selective acylation of an inactive congener and biological evaluation

Correction for ‘Synthesis of a fluorescent photoaffinity probe of OSW-1 by site-selective acylation of an inactive congener and biological evaluation’ by K. Sakurai et al., Chem. Commun., 2017, DOI: 10.1039/c6cc08955k.

AIDS, HIV and STD among Japanese and Japanese-Americans in San Francisco, California, USA

In affluent countries, some people may go abroad specifically for HIV testing or care for greater anonymity, better treatment, and less discrimination. A secondary analysis of data from the San Francisco Department of Public Health was conducted to characterize trends in AIDS incidence, AIDS care, sexually transmitted disease (STD) incidence, and HIV counselling and testing among Japanese in San Francisco. A total of 96 AIDS cases were diagnosed among ethnic Japanese, of whom 32 were born in Japan. From 1985 to 2000, 144 gonorrhoea and chlamydia cases were identified among Japanese. Of 368 self-identified Japanese seeking HIV counselling from 1995 to 1997, three (0.9%) were HIV-positive. The HIV/AIDS and STD epidemics among Japanese in San Francisco temporally parallels, but lags behind in magnitude, the epidemics for San Francisco's population as a whole. Some persons from Japan actively seek HIV/STD services while abroad. Our study points to several areas needing further research and improvements.

Anesthetic induction with etomidate, rather than propofol, is associated with increased 30-day mortality and cardiovascular morbidity after noncardiac surgery

BACKGROUND

Because etomidate impairs adrenal function and blunts the cortisol release associated with surgical stimulus, we hypothesized that patients induced with etomidate suffer greater mortality and morbidity than comparable patients induced with propofol.

METHODS

We evaluated the electronic records of 31,148 ASA physical status III and IV patients who had noncardiac surgery at the Cleveland Clinic. Among these, anesthesia was induced with etomidate and maintained with volatile anesthetics in 2616 patients whereas 28,532 were given propofol for induction and maintained with volatile anesthetics. Two thousand one hundred forty-four patients given etomidate were propensity matched with 5233 patients given propofol and the groups compared on 30-day postoperative mortality, length of hospital stay, cardiovascular and infectious morbidities, vasopressor requirement, and intraoperative hemodynamics.

RESULTS

Patients given etomidate had 2.5 (98% confidence interval [CI], 1.9-3.4) times the odds of dying than those given propofol. Etomidate patients also had significantly greater odds of having cardiovascular morbidity (odds ratio [OR] [98% CI]: 1.5 [1.2-2.0]), and significantly longer hospital stay (hazard ratio [95% CI]: 0.82 [0.78-0.87]). However, infectious morbidity (OR [98% CI]: 1.0 [0.8-1.2]) and intraoperative vasopressor use (OR [95% CI] 0.92: [0.82-1.0]) did not differ between the agents.

CONCLUSION

Etomidate was associated with a substantially increased risk for 30-day mortality, cardiovascular morbidity, and prolonged hospital stay. Our conclusions, especially on 30-day mortality, are robust to a strong unmeasured binary confounding variable. Although our study showed only an association between etomidate use and worse patients' outcomes but not causal relationship, clinicians should use etomidate judiciously, considering that improved hemodynamic stability at induction may be accompanied by substantially worse longer-term outcomes.

Low vitamin D concentration is not associated with increased mortality and morbidity after cardiac surgery

Objective

To determine the effect of vitamin D on postoperative outcomes in cardiac surgical patients.

Design

Retrospective study.

Setting

Single institution-teaching hospital.

Participants

Adult cardiac surgical patients with perioperative 25-hydroxyvitamin D measurements.

Interventions

None. We gathered information from the Cardiac Anesthesiology Registry that was obtained at the time of the patients’ visit/hospitalization.

Measurements and Main Results

We used data of 18,064 patients from the Cardiac Anesthesiology Registry; 426 patients with 25-hydroxyvitamin D measurements met our inclusion criteria. Association with Vitamin D concentration and composite of 11 cardiac morbidities was done by multivariate (i.e., multiple outcomes per subject) analysis. For other outcomes separate multivariable logistic regressions and adjusting for the potential confounders was used. The observed median vitamin D concentration was 19 [Q1-Q3∶12, 30] ng/mL. Vitamin D concentration was not associated with our primary composite of serious cardiac morbidities (odds ratio [OR], 0.96; 95% CI, 0.86–1.07). Vitamin D concentration was also not associated with any of the secondary outcomes: neurologic morbidity (P = 0.27), surgical (P = 0.26) or systemic infections (P = 0.58), 30-day mortality (P = 0.55), or length of initial intensive care unit (ICU) stay (P = 0.04).

Conclusions

Our analysis suggests that perioperative vitamin D concentration is not associated with clinically important outcomes, likely because the outcomes are overwhelmingly determined by other baseline and surgical factors.

IFPA Meeting 2012 Workshop Report II: epigenetics and imprinting in the placenta, growth factors and villous trophoblast differentiation, role of the placenta in regulating fetal exposure to xenobiotics during pregnancy, infection and the placenta

Workshops are an important part of the IFPA annual meeting as they allow for discussion of specialized topics. At IFPA meeting 2012 there were twelve themed workshops, four of which are summarized in this report. These workshops related to various aspects of placental biology: 1) epigenetics and imprinting in the placenta; 2) growth factors and villous trophoblast differentiation; 3) role of the placenta in regulating fetal exposure to xenobiotics during pregnancy; 4) infection and the placenta.

Airway scope for tracheal intubation in the lateral position

BACKGROUND

Tracheal intubation in the lateral position is difficult because the laryngeal view is compromised during direct laryngoscopy. The Airway Scope facilitates intubation even when laryngeal views are poor with direct laryngoscopy, as they often are in the lateral position. We thus compared the efficacy of the Airway Scope in supine patients with those in the left- and right-lateral positions.

METHODS

Anesthetized adults were randomly assigned to supine, left-lateral, or right-lateral position (n = 43 for each group). Laryngeal views were obtained in the designated position with a Macintosh laryngoscope, and patients' tracheas were subsequently intubated with the Airway Scope. Specifically, we tested the hypothesis that the time required for intubation in the left- and right-lateral positions is not increased by >10 seconds compared with tracheal intubation in the supine position.

RESULTS

Overall intubation success was 100% in the 2 lateral positions, and 98% in the supine position. Intubation times were similar in the left-lateral (24 [5] seconds, mean [SD]), right-lateral (24 [6] seconds), and supine (22 [7] seconds) positions. The numbers of required intubation attempts were similar in the 2 lateral positions and in the supine and left-lateral positions. However, more intubation attempts were required in the supine position than in the right-lateral position (P = 0.004). The incidences of airway complications were similar in each position; no hypoxia, dental injury, or esophageal intubation was observed. Modified Cormack-Lehane and the percentage of glottic opening scores obtained with the Macintosh laryngoscope did not differ between the 2 lateral positions, but the modified Cormack-Lehane and percentage of glottic opening scores were superior in the supine position (all P < 0.001) compared with either of the lateral positions.

CONCLUSIONS

Despite worse laryngoscopic views in either lateral position than when patients were supine, intubation with the Airway Scope offered high success rates. Furthermore, intubation time using the Airway Scope in either lateral position was not longer by >10 seconds than in the supine position. The Airway Scope thus seems to be a useful tool when tracheal intubation is required in a laterally positioned patient.

Predominant effects of midazolam for conscious sedation: benefits beyond the early postoperative period

PURPOSE

Conscious sedation with intravenous sedative-hypnotic drugs has the advantage of relaxing patients before invasive procedures. Preoperative anxiety has been suggested to correlate with postoperative comfortableness. In this study, we chose midazolam and droperidol as well-established intravenous sedative-hypnotic drugs. We evaluated the preoperative anxiolytic effect on postoperative memories and emotions up to the first postoperative morning.

METHODS

In a prospective, double blind study, 120 patients requiring epidural anesthesia were randomly assigned to one of three groups to receive saline, midazolam (0.04 mg/kg), or droperidol (0.1 mg/kg). Cardiovascular and respiratory measurements, observer's assessment of alertness/sedation scale, level of anxiety and discomfort of the patients, pain during the infiltration of local anesthetics, and incidence of adverse effects were recorded. Amnesia, anxiety, and discomfort during the epidural procedure were re-assessed between 12 and 20 h postsurgery.

RESULTS

Patients who received sedatives were significantly more sedated (P < 0.0001), but the pain score was significantly higher in the droperidol group (P = 0.0007) at epidural catheterization. On the first postoperative morning, patients receiving midazolam had a significantly lower pain score (P < 0.0001) with less anxiety and discomfort. Patients in both the midazolam and droperidol groups showed a significant decrease in blood pressure (P < 0.0167), but no respiratory impairment. No adverse effects were experienced throughout the study period.

CONCLUSION

Conscious sedation with intravenous midazolam 0.04 mg/kg significantly decreased the anxiety and discomfort scores of the patients on the day following surgery but had no effect on these immediately following the epidural catheterization procedure.

Factors influencing performance of Global Fund-supported tuberculosis grants

OBJECTIVE

To explore grant and country characteristics associated with the performance of tuberculosis (TB) grants supported by the Global Fund to Fight AIDS, Tuberculosis and Malaria (Global Fund), which uses performance-based funding of grants.

METHODS

We used Global Fund grant data to compute the average programmatic performance of 108 TB grants in 88 countries. Using stepwise regression models, we examined the correlation of grant performance with a range of grant and country characteristics.

RESULTS

Funding duration and funding per estimated smear-positive TB case were positively correlated with grant performance (partial correlations of 0.386-0.416 for the former, 0.200 for the latter). Successful completion of an evaluation of a grant during the second year of funding was linked to higher performance (0.357). Performance was further influenced by the independent organisation hired by the Global Fund to provide ongoing monitoring of the grants (0.197-0.243). Two country-specific factors were significantly correlated with performance: political stability (0.197-0.234) and disease burden (-0.211).

DISCUSSION

Successful evaluation that leads to continued funding predicts higher performance of TB grants, even in challenging settings such as weak health services. However, other contextual factors affect grant performance and should be considered when assessing grants to ensure that countries that have a high disease burden and are politically unstable are not penalized.

Airway scope and Macintosh laryngoscope for tracheal intubation in patients lying on the ground

BACKGROUND

Direct laryngoscopy of a patient lying on the ground is difficult because the intubator's head is far above the head of the patient, making alignment of the intubator's visual axis with the patient's tracheal axis difficult. The Airway Scope is a laryngoscope designed to facilitate tracheal intubation without requiring alignment of the oral, pharyngeal, and tracheal axes. We thus tested the hypothesis that intubation with the Airway Scope is faster than with the Macintosh laryngoscope in subjects lying on the ground.

METHODS

Adult surgical patients were enrolled. After anesthesia induction, direct laryngoscopy was performed and airway characteristics noted. Patients were randomly assigned to tracheal intubation by either the Airway Scope (n = 50) or the Macintosh laryngoscope (n = 50). The intubator performed tracheal intubation from a table positioned at the same height as that of the operating table, thus simulating intubating on the ground. An unblinded observer recorded overall intubation success rate, time required for intubation, the number of attempts required for successful intubation, and airway complications related to intubation. Of these, the primary end point was time required for intubation.

RESULTS

Overall intubation success rates were 98% with the Airway Scope and 100% with the Macintosh laryngoscope. Intubation was 17 s faster with the Airway Scope (mean, 18 (SD, 4) seconds) versus the Macintosh laryngoscope (35 (16) seconds). The number of intubation attempts was similar with each device. The incidences of airway complications were similar, with no hypoxia (Spo(2) <95%) occurring in either group.

CONCLUSIONS

Both the Airway Scope and the Macintosh laryngoscope offer high success rates in adequately prepared paralyzed patients lying supine at ground level in the hands of a skilled practitioner. However, the Airway Scope facilitated faster tracheal intubation.

[Anesthetic management of a patient with pheochromocytoma and end-stage renal disease]

We experienced anesthesia of a patient with pheochromocytoma on chronic hemodialysis who developed severe hypotension resistant to vasopressors after induction of general anesthesia. She was presented for spine surgery for destructive arthropathy of the cervical spine. Doxazosin up to 0.5 mg x day(-1) was administered for five days preoperatively for alpha-adrenergic blokade and regular hemodialysis was continued until the day before surgery without change in dry body weight. Blood pressure (BP) was within normal limits preoperatively. After induction of anesthesia with propofol and fentanyl, the patient developed hypotension with systolic BP of 60 mmHg which was resistant to vasopressor treatment with phenylephrine and ephedrine. After 45 minutes of volume replacement and commencement of dopamine and norepinephrine administration via a central venous catheter, BP recovered, and the surgery proceeded without further incident. Hypertension due to pheochromocytoma can be masked by excessive reduction of intravascular volume by preoperative hemodialysis. In a hemodialysed patient harboring pheochromocytoma who undergoes a surgical procedure unrelated to adrenalectomy, preoperative alpha-adrenergic blockade and subsequent intravascular volume expansion by increasing dry weight is required to avoid severe intraoperative hypotension, as for the case of adrenalectomy in the same situation.

[Perioperative management of a patient complicated with Quincke's edema]

We experienced perioperative management of a patient with Quincke's edema who underwent clipping of ruptured intracranial aneurysm. At the time of presentation, he complained of lip and tongue swelling. We administered dl-chlorpheniramine malate and tranexamic acid perioperatively to prevent further edema. Intraoperatively, we avoided contact of objects to the face and the oral cavity which might have caused mechanical stimuli, and infused albumin to maintain plasma osmotic pressure. The patient was kept intubated postoperatively because of significant tongue edema at the end of the procedure. On postoperative day 1, we extubated the trachea after prophylactic administration of methylpredonisolone. Significant upper airway edema was denied by flexible laryngoscopy. Pathophysiological cause of Quincke's edema is increased permeability of capillary vessels due to vasoactive substances. Aside from anti-histaminergic agents and steroids, tranexamic acid, which reduces production of kinin, is specifically effective for this condition. Although there is a reported case of Quincke's edema, eventually diagnosed after development of postoperative upper airway obstruction, there have been no reports of planned perioperative management of this condition. We demonstrated that Quincke's edema could be managed without life-threatening airway compromise by employing adequate pharmacologic interventions and sensible determination of the timing of extubation.

[Case of latex allergy manifested during cesarean section]

A 26-year-old G1P0 woman with past history of bronchial asthma underwent emergency cesarean section for non-reassuring fetal status under spinal anesthesia. She had not had surgery before. Thirteen minites after the start of the procedure, she started complaining of flushing and itching of her hands and mouth. We suspected anaphylactic reaction due to cefazolin, but after a thorough work up, it turned out that the symptom was manifestation of latex allergy. She had worked as a dental assistant and, had experienced mouth swelling by touching latex gloves. But she had not recognized it as a symptom of latex allergy. After the discharge from the hospital, she experienced food allergy. It is known that several antigens which cause latex allergy share common structures with defense related proteins of plants. It is to be noticed that, patients sensitized by those defense related proteins by plants intake, may develop latex allergy even though they are not considered to be high risk group from relevant occupational exposure and, co-morbid conditions. We should consider latex allergy as one of the causes of shock during intraoperative period even when the possibility of latex allergy seems scant.

[Perioperative management of a patient with deep vein thrombosis caused by estrogen producing granulosa cell tumor of the ovary]

We experienced perioperative management of a woman with large thrombi in femoral veins caused by estrogen producing ovarian tumor. At presentation, serum estradiol level was extremely high. Time constraint due to rapid expansion of the tumor did not allow us a trial of preoperative anti-coagulation. We placed a temporary IVC filter and proceeded with operation. As catastrophic pulmonary embolism could occur even with the presence of a filter, we prepared for institution of cardiopulmonary bypsss and pulmonary embolectomy via full sternotomy. We monitored arterial pressure based-cardiac output for immediate detection of pulmonary embolism. Postoperatively, serum estradiol level declined to normal range by postoperative day 7, and thrombi dissolved with anticoagulation therapy with warfarin and heparin without recurrence. In this case, surgery without preoperative anticoagulation was considered to pose extreme risk of perioperative pulmonary embolism. However, we considered that the thrombi would disolve by the removal of the tumor because estradiol production was the primary cause of thrombi. With above mentioned perioperative approach, the patient was managed uneventfully.

Suppression of shivering during hypothermia using a novel drug combination in healthy volunteers

BACKGROUND

Hypothermia may be beneficial in stroke victims; however, it provokes vigorous shivering. Buspirone and dexmedetomidine each linearly reduce the shivering threshold with minimal sedation and no respiratory depression. This study tested the hypotheses that the combination of buspirone and dexmedetomidine would (1) synergistically reduce the shivering threshold, (2) synergistically reduce the gain and maximum intensity of shivering, and (3) produce sufficient inhibition to permit cooling to 34 degrees C without excessive hypotension or sedation.

METHODS

Eight healthy men were randomly assigned on 4 days to (1) no drug, (2) buspirone (60 mg orally), (3) dexmedetomidine (intravenous infusion to target plasma concentration of 0.6 ng/ml), or (4) combination of buspirone and dexmedetomidine at same doses. Lactated Ringer's solution (approximately 3 degrees C) was infused intravenously to decrease tympanic membrane temperature by 1.5 degrees C/h. Shivering threshold was defined as an increase in oxygen consumption greater than 20%. Sedation was evaluated using the Observer's Assessment of Sedation/Alertness scale.

RESULTS

Mean arterial pressure and heart rate were slightly lower on dexmedetomidine and combination days. Likewise, the level of sedation was statistically different on these 2 days but clinically unimportant. Buspirone reduced the shivering threshold from 36.6 degrees C +/- 0.4 degrees C to 35.9 degrees C +/- 0.4 degrees C, dexmedetomidine reduced it to 34.7 degrees C +/- 0.5 degrees C, and the combination to 34.1 +/- 0.4 degrees C. The interaction effect of 0.04 degrees C was not significant. The gain of shivering and maximum shivering intensity were similar on each day.

CONCLUSIONS

The combination of buspirone and dexmedetomidine additively reduced the shivering threshold. Thus, supplementing dexmedetomidine with buspirone blocks shivering and causes only minimal sedation.

Effect of nasal cannula oxygen administration on oxygen concentration at facial and adjacent landmarks

An oxygen-enriched atmosphere enhances the potential for operating-room fires. We thus determined oxygen concentrations at various facial landmarks during oxygen administration via nasal cannulae. Thirteen supine volunteers were draped similarly to patients undergoing a cervical-node biopsy. Oxygen was delivered in random order through nasal cannulae at rates of 2, 4, and 6 l x min(-1). Oxygen concentration was measured at pre-determined facial landmarks and also distal to the drape at non-facial sites. At a flow of 2 l x min(-1), oxygen concentrations exceeded 23% only within a few centimetres of the nasal cannula. Concentration increased as a function of flow, but rarely exceeded 26%. At all flow rates, concentrations distal to the drape were < 24%. To reduce combustion risk, ignition sources should be kept at least 10 cm from the oxygen outlet when using nasal cannula at a flow rate > or = 4 l x min(-1).

Estimating the number of HIV infections averted: an approach and its issues

Objective:

To propose a methodology to estimate the number of new HIV infections averted. Knowledge of HIV infection has increased tremendously and modelling tools to project current epidemics into the future have greatly improved. Different types of models can be used to estimate HIV infections averted, although the number of new HIV infections averted cannot be measured directly.

Method:

Using cohort-component population projections, a disease modelling-based approach was used to compare the observed epidemiology of a disease after programme initiation with an expected epidemiology from past trends before programme initiation. The concept of modelling infections averted in a disease modelling-based approach involves a comparison between an “expected” or baseline epidemic with an “estimated” one. A hypothetical example was featured in order to demonstrate the proposed methodology. Using both the Estimation and Projection Package (EPP) and the Spectrum demographic modelling program, the underlying annual incidence levels implied by both the baseline and estimated epidemics were examined.

Results:

The difference between baseline and estimated incidence levels is interpreted as “infections averted”. Strengths and limitations of the approach are discussed.

Conclusions:

In this study an expected epidemiological approach was compared to one based on observation. Once sufficient data become available, the validation of various country data including HIV prevalence, mortality, and behaviour must be done. Additional information related to behaviour change may be critical to further support arguments for a change in disease trend. It is therefore important to use all available data, consequently strengthening findings from a disease modelling-based approach on HIV infections averted.

New circulating-water devices warm more quickly than forced-air in volunteers

BACKGROUND

Newer circulating-water systems supply more heat than forced-air, mainly because the heat capacity of water is much greater than for that of dry warm air and, in part, because they provide posterior as well as anterior heating. Several heating systems are available, but three major ones have yet to be compared directly. We therefore compared two circulating-water systems with a forced-air system during simulation of upper abdominal or chest surgery in volunteers.

METHODS

Seven healthy volunteers participated on three separate study days. Each day, they were anesthetized and cooled to a core temperature near 34 degrees C, which was maintained for 45-60 min. They were then rewarmed with one of three warming systems until distal esophageal core temperature reached 36 degrees C or anesthesia had lasted 8 h. The warming systems were 1) energy transfer pads (two split torso pads and two universal pads; Kimberly Clark, Roswell, GA); 2) circulating-water garment (Allon MTRE 3365 for cardiac surgery, Akiva, Israel); and 3) lower body forced-air warming (Bair Hugger #525, #750 blower, Eden Prairie, MN). Data are presented as mean +/- sd; P < 0.05 was statistically significant.

RESULTS

The rate of increase of core temperature from 34 degrees C to 36 degrees C was 1.2 degrees C +/- 0.2 degrees C/h with the Kimberly Clark system, 0.9 degrees C +/- 0.2 degrees C/h with the Allon system, and 0.6 degrees C +/- 0.1 degrees C/h with the Bair Hugger (P = 0.002).

CONCLUSIONS

The warming rate with the Kimberly Clark system was 25% faster than with the Allon system and twice as fast as with the Bair Hugger. Both circulating-water systems thus warmed hypothermic volunteers in significantly less time than the forced-air system.