Preoperative Versus Extended Postoperative Antimicrobial Prophylaxis of Surgical Site Infection During Spinal Surgery: A Comprehensive Systematic Review and Meta-Analysis.

INTRODUCTION: Surgical site infection (SSI) following spinal surgery is a major source of postoperative morbidity. Although studies have demonstrated perioperative antimicrobial prophylaxis (AMP) to be beneficial in the prevention of SSI among spinal surgery patients, consensus is lacking over whether preoperative or extended postoperative AMP is most efficacious. To date, no meta-analysis has investigated the comparative efficacy of these two temporally variable AMP protocols in spinal surgery. We undertook a systemic review and meta-analysis to determine whether extended postoperative AMP is associated with a difference in the rate of SSI occurrence among adult patients undergoing spinal surgery. METHODS: Embase and MEDLINE databases were systematically searched for clinical trials and cohort studies directly comparing SSI rates among adult spinal surgery patients receiving either preoperative or extended postoperative AMP. Quality of evidence of the overall study population was evaluated using the Grading of Recommendations Assessment, Development and Evaluation (GRADE) Working Group approach. Random effects meta-analyses were performed utilizing both pooled and stratified data based on instrumentation use. RESULTS: Five studies met inclusion criteria. No individual study demonstrated a significant difference in the rate of SSI occurrence between preoperative and extended postoperative AMP protocols. The GRADE quality of evidence was low. Among the overall cohort of 2824 patients, 96% underwent lumbar spinal surgery. Pooled SSI rates were 1.38% (26/1887) for patients receiving extended postoperative AMP and 1.28% (12/937) for patients only receiving preoperative AMP. The risk of SSI development among patients receiving extended postoperative AMP was not significantly different from the risk of SSI development among patients only receiving preoperative AMP [RR (risk ratio), 1.11; 95% CI (confidence interval) 0.53-2.36; p = 0.78]. The difference in risk of SSI development when comparing extended postoperative AMP to preoperative AMP was also not significant for both instrumented (RR, 0.92; 95% CI 0.15-5.75; p = 0.93) and non-instrumented spinal surgery (RR, 1.25; 95% CI 0.49-3.17; p = 0.65). There was no evidence of heterogeneity of treatment effects for all meta-analyses. CONCLUSION: Preoperative AMP appears to provide equivalent protection against SSI development when compared to extended postoperative AMP. Prudent antibiotic use is also known to decrease hospital length of stay, healthcare expenditure, and risk of complications. However, until higher-quality evidence becomes available regarding AMP in spinal surgery, surgeons should continue to exercise discretion and clinical judgment when weighing the effects of patient comorbidities and complications before determining the optimal duration of perioperative AMP.

The impact of weather, road surface, time-of-day, and light conditions on severity of bicycle-motor vehicle crash injuries.

BACKGROUND: This study examined whether environmental variables including weather, road surface, time-of-day, and light conditions were associated with the severity of injuries resulting from bicycle-motor vehicle crashes. METHODS: Using log-binomial regressions, we analyzed 113 470 police reports collected between 2000 and 2014 in four U.S. states with environmental and injury severity information. "Severe" injuries included fatal and incapacitating injuries, and "non-severe" included non-incapacitating, possible or no-injuries. RESULTS: Light condition was significantly associated with the injury severity to the bicyclist with more severe injuries at dawn (RR = 1.62 [95%CI 1.35-1.94]) and during darkness (both lighted and unlighted roads: 1.32 [1.24-1.40], respectively, 1.57 [1.41-1.76]) as compared to daylight. In these conditions of low visibility, risk was further increased during early morning hours before 7 am (1.61 [1.22-2.13]). CONCLUSIONS: Crashes in low light conditions and during early morning hours are more likely to result in higher injury severity.

Predictive Value of Tracheal Rapid Ultrasound Exam Performed in the Emergency Department for Verification of Tracheal Intubation.

BACKGROUND: Verification of the correct placement of the endotracheal tube (ETT) has been one of the most challenging issues of airway management in the field of emergency medicine. Early detection of oesophagal intubation through a reliable method is important for emergency physicians. AIM: The aim of this study was to assess the diagnostic accuracy of tracheal rapid ultrasound exam (TRUE) to assess endotracheal tube misplacement during emergency intubation. METHODS: This was an observational prospective study performed in the emergency department of the major tertiary referral hospital in the city. We included a consecutive selection of 100 patients. TRUE was performed for all these patients, and subsequently, quantitative waveform capnography was done. The later test is considered as the gold standard. RESULTS: From our total 100 eligible patients, 93 (93%) participants had positive TRUE results (tracheal intubation) and 7 (7%) patients have negative TRUE results (esophageal intubation). Quantitative waveform capnography report of all 93 (100%) patients who had positive TRUE was positive (appropriate tracheal placement). Sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV) of TRUE for detecting appropriate tracheal placement of ETT were 98.9% (95% CI, 93.3% to 99.8%), 100% (95% CI, 51.6% to 100%), 100% (95% CI, 95.1% to 100%) and 85.7% (95% CI, 42% to 99.2%) respectively. CONCLUSIONS: Performing TRUE is convenient and feasible in many emergency departments and pre-hospital settings. We would recommend emergency units explore the possibility of using TRUE as a method in the assessment of proper ETT placement.

Antibacterial prophylaxis for gram-positive and gram-negative infections in cranial surgery: A meta-analysis.

BACKGROUND: Perioperative antibiotic prophylaxis against gram positive and gram negative infections is considered standard of care in the perioperative management of patients undergoing cranial surgery. The antibiotic regimen which best reduces the risk of surgical site infections (SSIs) remains controversial. OBJECTIVES: A systematic literature review and meta-analysis were conducted to examine the effect of various prophylactic antibiotics on infection incidence among patients undergoing cranial surgeries. METHODS: A comprehensive search was conducted on Pubmed, EMBASE and Cochrane databases through October 2014 for studies that evaluated the efficacy of antibiotic prophylaxis among patients undergoing cranial surgeries. Pooled effect estimates using both fixed- and random-effect models were calculated. RESULTS: Eight articles were included in the meta-analysis, with a combined total of 1655 cranial procedures. Among these, 74 cases of SSIs were reported after patients received a single antibiotic or a combination of 2 or more antibiotics (pooled incidence of SSIs=6.00%; 95% CI=4.80%, 7.50%; fixed-effects model; I2=73.7%; P-heterogeneity<0.01). Incidence of SSI was 1.00% (95% CI=0.40%, 2.60%) for non-MRSA gram-positive bacterial infections; 2.70% (95% CI=0.90%, 8.00%) for gram-negative bacterial infections; 6.00% (95% CI=4.50%, 7.80%) for gram negative, and non-MRSA gram-positive bacterial infections; and 11.3% (95% CI=7.20%, 17.4%) for gram negative and MRSA gram-positive bacterial infections. Subgroup analysis revealed an effect modification by drug class (P=0.05) and infection type (P-interaction=0.01). More specifically, lincosamides (2.70%; n=1 group), glycopeptides (2.80%; n=1), third generation cephalosporins (5.30%; n=2), antibiotics combination (4.90%; n=4), and penicillin-family antibiotics (5.90%, n=1) offered better coverage against infections than first generation cephalosporins (22.0%; n=2). A meta-regression analysis on study length was not significant (P=0.13). Random-effect models were not materially different form fixed-effects. No evidence of publication bias was found. CONCLUSION: Lincosamides, glycopeptides, third generation cephalosporins, other combinations of prophylactic antibiotics, or penicillin-family antibiotics alone offer better coverage against SSIs than first generation cephalosporin among cranial surgery patients.

Thoracic Injury Rule out Criteria in Prediction of Traumatic Intra-thoracic Injuries; a Validation Study.

INTRODUCTION: Doing Chest X Ray (CXR) for all trauma patients is not efficient and cost effective due to its low diagnostic value. The present study was designed aiming to evaluate the diagnostic accuracy of thoracic injury rule out criteria (TIRC) in prediction of traumatic intra-thoracic injuries and need for CXR. METHOD: The present study is a prospective cross-sectional study that has been carried out to evaluate the accuracy of TIRC model in screening blunt multiple trauma patients in need of CXR for ruling out intra-thoracic injuries. RESULTS: 1518 patients with the mean age of 33.53 ± 15.42 years were enrolled (80.4% male). The most common mechanisms of trauma were motor car accident (78.8%) and falling (13.6%). Area under the ROC curve, sensitivity, and specificity of model in detection of traumatic thoracic injuries was 0.95 (95% CI: 0.93 - 0.97), 100 (95% CI: 87.0 - 100), and 80.1 (95% CI: 78.0 - 82.1), respectively. Brier score for TIRC was 0.02 and its scaled reliability was 0.0002. CONCLUSION: Findings of the present study showed that TIRC has high accuracy in prediction of traumatic intra-thoracic injuries and screening patients in need of CXR.

The role of intersection and street design on severity of bicycle-motor vehicle crashes.

BACKGROUND: Safety concerns are a major barrier to cycling. Intersection and street design variables such as intersection angles and street width might contribute to the severity of crashes and the safety concerns. In this study we examined whether these design variables were associated with bicycle-motor vehicle crashes (BMVC) severity. METHODS: Using the geographical information system and latitudes/longitudes recorded by the police using a global positioning device, we extracted intersection angles, street width, bicycle facilities, posted speed limits and annual average daily traffic from 3266 BMVC data from New York City police records. Additional variables about BMVC, including age and sex of the bicyclist, time of the day, road surface conditions, road character, vehicle type and injury severity, were obtained from police reports. Injury severity was classified as severe (incapacitating or killed) or non-severe (non-incapacitating, possible injury). The associations between injury severity and environment design variables were examined using multivariate log-binomial regression model. FINDINGS: Compared with crashes at orthogonal intersections, crashes at non-orthogonal intersections had 1.37 times (95% CI 1.05 to 1.80) and non-intersection street segments had 1.31 times (95% CI 1.01 to 1.70) higher risk of a severe injury. Crashes that involved a truck or a bus were twice as likely to result in a severe injury outcome; street width was not significantly associated with injury severity. CONCLUSION: Crashes at non-orthogonal intersections and non-intersection segments are more likely to result in higher injury severity. The findings can be used to improve road design and develop effective safety interventions.

Serum concentration of magnesium as an independent risk factor in migraine attacks: a matched case-control study and review of the literature.

There is controversy over the role of magnesium in the etiology of migraine headaches. We aimed to evaluate and compare serum levels of magnesium between healthy individuals and those with migraine headaches during migraine attacks and between attacks to evaluate the role of magnesium in the etiology of migraine headaches. Forty patients with migraine headaches and 40 healthy individuals were enrolled in this matched case-control study. Malnutrition, digestive system disorders, history of smoking, drug abuse, and history of medications use were recorded at baseline. The pain scores of patients were measured and recorded based on a 10 cm visual analog scale. Subsequently, blood samples were collected at 8-10 in the morning to determine serum levels of magnesium. Analysis of variance, χ-test, and conditional logistic regression were used for data analysis. There were no significant differences in demographic data between the two groups. There were significant differences in magnesium serum levels between the three groups (1.09±0.2 mg/dl during migraine headaches; 1.95±0.3 mg/dl between the attacks; and 1.3±0.4 mh/dl in the control group; P<0.0001). Odds of acute migraine headaches increased 35.3 times (odds ratio=35.3; 95% confidence interval: 12.4-95.2; P=0.001) when serum levels of magnesium reached below the normal level. The odds in patients who are not in the acute attack phase were 6.9 folds higher (odds ratio=6.9; 95% confidence interval: 1.3-2.1; P=0.02). The serum level of magnesium is an independent factor for migraine headaches and patients with migraine have lower serum levels of magnesium during the migraine attacks and between the attacks compared with healthy individuals.

The Efficacy of Antibacterial Prophylaxis Against the Development of Meningitis After Craniotomy: A Meta-Analysis.

OBJECTIVE: Prophylactic antibiotics are widely used before craniotomy to prevent postoperative infections. A systematic review and meta-analysis was conducted to examine the effect of prophylactic antibiotics on meningitis after craniotomy. METHODS: PubMed, EMBASE, and Cochrane databases were searched through October 2014 for randomized controlled trials that evaluated the effect of prophylactic antibiotics on meningitis after craniotomy. Pooled effect estimates were calculated using fixed-effects and random-effects models. RESULTS: Seven studies with 2365 patients were included in the final analysis. All studies were randomized controlled trials with different antibiotic regimens. Prophylactic antibiotic use reduced the rate of meningitis after neurosurgery, with a pooled Peto odds ratio of 0.34 (95% confidence interval 0.18-0.63). Cochran's Q test indicated no significant heterogeneity among studies (I(2) = 0; P value for heterogeneity = 0.44). Subgroup analysis based on Gram-negative coverage, blinding design, and study quality demonstrated no statistically significant difference among these groups (P> 0.05 for all). A meta-regression on surgery duration (P = 0.52) and on antibiotics duration (P = 0.59) did not show significant differences in the results among studies. CONCLUSIONS: This meta-analysis shows that prophylactic antibiotic use significantly decreases meningitis infections after craniotomy.

Database improvements for motor vehicle/bicycle crash analysis.

BACKGROUND: Bicycling is healthy but needs to be safer for more to bike. Police crash templates are designed for reporting crashes between motor vehicles, but not between vehicles/bicycles. If written/drawn bicycle-crash-scene details exist, these are not entered into spreadsheets. OBJECTIVE: To assess which bicycle-crash-scene data might be added to spreadsheets for analysis. METHODS: Police crash templates from 50 states were analysed. Reports for 3350 motor vehicle/bicycle crashes (2011) were obtained for the New York City area and 300 cases selected (with drawings and on roads with sharrows, bike lanes, cycle tracks and no bike provisions). Crashes were redrawn and new bicycle-crash-scene details were coded and entered into the existing spreadsheet. The association between severity of injuries and bicycle-crash-scene codes was evaluated using multiple logistic regression. RESULTS: Police templates only consistently include pedal-cyclist and helmet. Bicycle-crash-scene coded variables for templates could include: 4 bicycle environments, 18 vehicle impact-points (opened-doors and mirrors), 4 bicycle impact-points, motor vehicle/bicycle crash patterns, in/out of the bicycle environment and bike/relevant motor vehicle categories. A test of including these variables suggested that, with bicyclists who had minor injuries as the control group, bicyclists on roads with bike lanes riding outside the lane had lower likelihood of severe injuries (OR, 0.40, 95% CI 0.16 to 0.98) compared with bicyclists riding on roads without bicycle facilities. CONCLUSIONS: Police templates should include additional bicycle-crash-scene codes for entry into spreadsheets. Crash analysis, including with big data, could then be conducted on bicycle environments, motor vehicle potential impact points/doors/mirrors, bicycle potential impact points, motor vehicle characteristics, location and injury.

Public health 101 nanocourse: a condensed educational tool for non-public health professionals.

Graduate students and postdoctoral fellows-including those at the Harvard School of Public Health (HSPH)-have somewhat limited opportunities outside of traditional coursework to learn holistically about public health. Because this lack of familiarity could be a barrier to fruitful collaboration across disciplines, HSPH postdocs sought to address this challenge. In response, the Public Health 101 Nanocourse was developed to provide an overview of five core areas of public health (biostatistics, environmental health sciences, epidemiology, health policy and management, and social and behavioral sciences) in a two half-day course format. We present our experiences with developing and launching this novel approach to acquainting wider multidisciplinary audiences with the field of public health.

Comparison of therapeutic effects of magnesium sulfate vs. dexamethasone/metoclopramide on alleviating acute migraine headache.

BACKGROUND: There is controversy about the efficacy of currently used treatment modalities to alleviate migraine headaches. OBJECTIVE: We aimed to evaluate and compare the effects of magnesium sulfate and combined use of dexamethasone/metoclopramide on relieving acute migraine headache. METHODS: We randomly divided 70 patients who had been referred to an emergency department, into two equal treatment groups with the two treatment plans, and analyzed pain severity at baseline using a numeric rating scale (NRS). We gave dexamethasone/metoclopramide to one group and magnesium sulfate to the other group, and evaluated pain severity at 20 min and at 1- and 2-h intervals after infusion. Finally, we used repeated-measure and two-way analysis of variance for intra- and inter-group evaluations of pain severity and complications, respectively. RESULTS: We found no significant differences in demographic data and pain severity at baseline (8.2 vs. 8.0) between the two groups (p < 0.05). In the dexamethasone/metoclopramide group, pain severity (mean ± standard deviation) was 7.4 ± 1.4 (p = 0.36), 6.0 ± 2.4, and 2.5 ± 2.9 (p < 0.0001) at 20-min, 1-h, and 2-h intervals after treatment, respectively, with statistically significant differences between the baseline values and 1-h and 2-h interval values. Administration of magnesium sulfate was associated with decreased pain severity at the three intervals (5.2 ± 1.7, 2.3 ± 1.9, and 1.3 ± 0.66, respectively), exhibiting significant differences compared to baseline values and the corresponding time intervals in the dexamethasone/metoclopramide group (p < 0.0001). CONCLUSIONS: According to the results, magnesium sulfate was a more effective and fast-acting medication compared to a combination of dexamethasone/metoclopramide for the treatment of acute migraine headaches.

Weight training, aerobic physical activities, and long-term waist circumference change in men.

OBJECTIVE: Findings on weight training and waist circumference (WC) change are controversial. This study examined prospectively whether weight training, moderate to vigorous aerobic activity (MVAA), and replacement of one activity for another were associated with favorable changes in WC and body weight (BW). METHODS: Physical activity, WC, and BW were reported in 1996 and 2008 in a cohort of 10,500 healthy U.S. men in the Health Professionals Follow-up Study. Multiple linear regression models (partition/substitution) to assess these associations were used. RESULTS: After adjusting for potential confounders, a significant inverse dose-response relationship between weight training and WC change (P-trend <0.001) was observed. Less age-associated WC increase was seen with a 20-min/day activity increase; this benefit was significantly stronger for weight training (-0.67 cm, 95% CI -0.93, -0.41) than for MVAA (-0.33 cm, 95% CI -0.40, -0.27), other activities (-0.16 cm, 95% CI -0.28, -0.03), or TV watching (0.08 cm, 95% CI 0.05, 0.12). Substituting 20 min/day of weight training for any other discretionary activity had the strongest inverse association with WC change. MVAA had the strongest inverse association with BW change (-0.23 kg, 95% CI -0.29, -0.17). CONCLUSIONS: Among various activities, weight training had the strongest association with less WC increase. Studies on frequency/volume of weight training and WC change are warranted.