Background

Acute pancreatitis remains the most common major complication of endoscopic retrograde cholangiopancreatography (ERCP). The pathogenesis of post-ERCP acute pancreatitis may be mediated by oxygen-derived free radicals, which could be ameliorated by antioxidants. Antioxidant supplementation may potentially prevent post-ERCP pancreatitis. We performed a meta-analysis of randomized controlled trials to evaluate the effect of prophylactic antioxidant supplementation compared with control on the prevention of post-ERCP pancreatitis.

Methods

PubMed and Embase databases were searched to identify relevant trials. A standardized Excel file was used to extract data by two independent authors. Results were expressed as risk ratio (RR) with accompanying 95% confidence interval (CI). The meta-analysis was performed with the fixed-effects model or random-effects model according to heterogeneity.

Results

Eleven studies involving 3,010 patients met our inclusion criteria. Antioxidant supplementation did not significantly decrease the incidence of post-ERCP pancreatitis (RR, 0.92; 95% CI, 0.65-1.32; P = 0.665). There was also no statistical difference in the severity grades between the antioxidant group and control group.

Conclusions

Based on current evidence, antioxidant supplementation shows no beneficial effect on the incidence and the severity of post-ERCP pancreatitis; thus, there is currently a lack of evidence to support using antioxidants for the prevention of post-ERCP pancreatitis.

Background

Postoperative atrial fibrillation (POAF) is one of the most common complications in patients undergoing coronary artery bypass grafting (CABG). The goal of this meta-analysis was to evaluate the efficacy of thoracic epidural anesthesia (TEA) in preventing POAF in adult patients undergoing CABG.

Methods

MEDLINE and EMBASE were searched to identify randomized controlled trails in adult patients undergoing CABG who were randomly assigned to receive general anesthesia plus thoracic epidural anesthesia (GA + TEA) or general anesthesia only (GA). Two authors independently extracted data using a standardized Excel file. The primary outcome measure was the incidence of POAF. We used DerSimonian-Laird random-effects models to compute summary risk ratios with 95% confidence intervals.

Results

Five studies involving 540 patients met our inclusion criteria. No significant difference in the incidence of POAF was observed between the two groups (risk ratio, 0.61; 95% confidence interval, 0.33 to 1.12; P = 0.11), with significant heterogeneity among the studies (I2 = 73%, P = 0.005). Sensitivity analyses by primary endpoint, methodological quality and surgical technique yielded similar results.

Conclusions

The limited evidence suggests that TEA shows no beneficial efficacy in preventing POAF in adult patients undergoing CABG. However, the results of this meta-analysis should be interpreted with caution due to significant heterogeneity of the studies included. Thus, the potential infuence of TEA on the incidence of atrial fibrillation following CABG warrants further investigation.

Background

Postoperative atrial fibrillation (POAF) is the most common complication after coronary artery bypass grafting (CABG). The preventive effect of magnesium on POAF is not well known. This meta-analysis was undertaken to assess the efficacy of intravenous magnesium on the prevention of POAF after CABG.

Methods

Eligible studies were identified from electronic databases (Medline, Embase, and the Cochrane Library). The primary outcome measure was the incidence of POAF. The meta-analysis was performed with the fixed-effect model or random-effect model according to heterogeneity.

Results

Seven double-blind, placebo-controlled, randomized clinical trials met the inclusion criteria including 1,028 participants. The pooled results showed that intravenous magnesium reduced the incidence of POAF by 36% (RR 0.64; 95% confidence interval (CI) 0.50-0.83; P = 0.001; with no heterogeneity between trials (heterogeneity P = 0.8, I2 = 0%)).

Conclusions

This meta-analysis indicates that intravenous magnesium significantly reduces the incidence of POAF after CABG. This finding encourages the use of intravenous magnesium as an alternative to prevent POAF after CABG. But more high quality randomized clinical trials are still need to confirm the safety.

Background

Atrial fibrillation is the most common type of arrhythmia after cardiac surgery. An increasing body of evidence demonstrates that oxidative stress plays a pivotal role in the pathophysiology of atrial fibrillation. N-acetylcysteine (NAC) is a free radical scavenger, and may attenuate this pathophysiologic response and reduce the incidence of postoperative AF (POAF). However, it is unclear whether NAC could effectively prevent POAF. Therefore, this meta-analysis aims to assess the efficacy of NAC supplementation on the prevention of POAF.

Methods

Medline and Embase were systematically reviewed for studies published up to November 2011, in which NAC was compared with controls for adult patients undergoing cardiac surgery. Outcome measures comprised the incidence of POAF and hospital length of stay (LOS). The meta-analysis was performed with the fixed-effect model or random-effect model according to the heterogeneity.

Results

Eight randomized trials incorporating 578 patients provided the best evidence and were included in this meta-analysis. NAC supplementation significantly reduced the incidence of POAF (OR 0.62, 95% CI 0.41 to 0.93; P = 0.021) compared with controls, but had no effect on LOS (WMD -0.07, 95% CI -0.42 to 0.28; P = 0.703).

Conclusions

The prophylactic NAC supplementation may effectively reduce the incidence of POAF. However, the overall quality of current studies is poor and further research should focus on adequately powered randomized controlled trials with POAF incidence as a primary outcome measure.