Benefit and Harm of Adding Epinephrine to a Local Anesthetic for Neuraxial and Locoregional Anesthesia: A Meta-analysis of Randomized Controlled Trials With Trial Sequential Analyses.

BACKGROUND: This systematic review examines the benefit and harm of adding epinephrine to local anesthetics for epidural, intrathecal, or locoregional anesthesia. METHODS: We searched electronic databases to October 2017 for randomized trials comparing any local anesthetic regimen combined with epinephrine, with the same local anesthetic regimen without epinephrine, reporting on duration of analgesia, time to 2 segments regression, or any adverse effects. Trial quality was assessed using the Cochrane risk of bias tool and a random-effects model was used. Trial sequential analyses (TSA) were applied to identify the information size (IS; number of patients needed to reach a definite conclusion) and were set to detect an increase or decrease of effect of 30%-50%, depending on the end point considered. Alpha levels were adjusted (1%) for multiple outcome testing. RESULTS: We identified 70 trials (3644 patients, 17 countries, from 1970 to 2017). Median number of patients per trial was 44 (range, 9-174). Thirty-seven trials (1781 patients) tested epinephrine for epidural, 27 (1660) for intrathecal, and 6 (203) for locoregional anesthesia (sciatic, femoral, popliteal, axillary blocks). TSA enabled us to conclude that adding epinephrine to epidural local anesthetics could not decrease postoperative pain intensity by 30%, and did not impact the risk of intraoperative arterial hypotension. IS was insufficient to conclude on the impact of epinephrine on the risk of motor block (IS, 4%), arterial hypotension (20%), urinary retention (23%), or pain intensity at rest (27%) during labor. TSA confirmed that adding epinephrine to intrathecal local anesthetics increased the duration of motor block (weighted mean difference [WMD] 64 minutes; 99% CI, 37-91), analgesia (WMD 34 minutes; 99% CI, 6-62), and the time to 2 segments regression (WMD 20 minutes; 99% CI, 11-28). IS was insufficient to conclude on its impact on arterial hypotension (IS, 15%), or when administrated in a combined spinal-epidural, on motor block (IS, 11%) or arterial hypotension (IS, 11%). Adding epinephrine to local anesthetics for a locoregional block increased the duration of analgesia (WMD 66 minutes; 98% CI, 32-100]). CONCLUSIONS: Adding epinephrine to intrathecal or locoregional local anesthetics prolongs analgesia and motor block by no more than 60 minutes. The impact of adding epinephrine to epidural local anesthetics or to a combined spinal-epidural remains uncertain.

Predictors of Heavy Stethoscope Contamination Following a Physical Examination.

BACKGROUND The degree of bacterial contamination of stethoscopes can vary significantly following a physical examination. OBJECTIVE To conduct a prospective study to investigate the impact of various environmental and patient characteristics on stethoscope contamination. METHODS Following a standardized examination, the levels of bacterial contamination of 4 regions of the physicians' hands and 2 sections of the stethoscopes, and the presence of different pathogenic bacteria, were assessed. Predictors of heavy stethoscope contamination were identified through multivariate logistic regression. RESULTS In total, 392 surfaces were sampled following examination of 56 patients. The microorganisms most frequently recovered from hands and stethoscopes were Enterococcus spp. (29% and 20%, respectively) and Enterobacteriaceae (16% and 7%, respectively). Staphylococcus aureus (either methicillin susceptible or resistant), extended-spectrum ß-lactamase-producing Enterobacteriaceae, and Acinetobacter baumannii were recovered from 4%-9% of the samples from either hands or stethoscopes. There was a correlation between the likelihood of recovering these pathogens from the stethoscopes vs from the physicians' hands (ρ=0.79; P=.04). The level of patient's skin contamination was an independent predictor of contamination of the stethoscope diaphragm (adjusted odds ratio [aOR], 1.001; P=.007) and tube (aOR, 1.001; P=.003). Male sex (aOR, 28.24; P=.01) and reception of a bed bath (aOR, 7.52; P=.048) were also independently associated with heavy tube contamination. CONCLUSIONS Stethoscope contamination following a single physical examination is not negligible and is associated with the level of contamination of the patient's skin. Prevention of pathogen dissemination is needed. Infect Control Hosp Epidemiol 2016;37:673-679.

Contamination of stethoscopes and physicians' hands after a physical examination.

OBJECTIVES: To compare the contamination level of physicians' hands and stethoscopes and to explore the risk of cross-transmission of microorganisms through the use of stethoscopes. PATIENTS AND METHODS: We conducted a structured prospective study between January 1, 2009, and May 31, 2009, involving 83 inpatients at a Swiss university teaching hospital. After a standardized physical examination, 4 regions of the physician's gloved or ungloved dominant hand and 2 sections of the stethoscopes were pressed onto selective and nonselective media; 489 surfaces were sampled. Total aerobic colony counts (ACCs) and total methicillin-resistant Staphylococcus aureus (MRSA) colony-forming unit (CFU) counts were assessed. RESULTS: Median total ACCs (interquartile range) for fingertips, thenar eminence, hypothenar eminence, hand dorsum, stethoscope diaphragm, and tube were 467, 37, 34, 8, 89, and 18, respectively. The contamination level of the diaphragm was lower than the contamination level of the fingertips (P<.001) but higher than the contamination level of the thenar eminence (P=.004). The MRSA contamination level of the diaphragm was higher than the MRSA contamination level of the thenar eminence (7 CFUs/25 cm(2) vs 4 CFUs/25 cm(2); P=.004). The correlation analysis for both total ACCs and MRSA CFU counts revealed that the contamination level of the diaphragm was associated with the contamination level of the fingertips (Spearman's rank correlation coefficient, ρ=0.80; P<.001 and ρ=0.76; P<.001, respectively). Similarly, the contamination level of the stethoscope tube increased with the increase in the contamination level of the fingertips for both total ACCs and MRSA CFU counts (ρ=0.56; P<.001 and ρ=.59; P<.001, respectively). CONCLUSION: These results suggest that the contamination level of the stethoscope is substantial after a single physical examination and comparable to the contamination of parts of the physician's dominant hand.