Prophylactic abdominal drainage for pancreatic surgery.

BACKGROUND: The use of surgical drains has been considered mandatory after pancreatic surgery. The role of prophylactic abdominal drainage to reduce postoperative complications after pancreatic surgery is controversial.

OBJECTIVES: To assess the benefits and harms of routine abdominal drainage after pancreatic surgery, compare the effects of different types of surgical drains, and evaluate the optimal time for drain removal.

SEARCH METHODS: We searched The Cochrane Library (2015, Issue 3), MEDLINE (1946 to 9 April 2015), EMBASE (1980 to 9 April 2015), Science Citation Index Expanded (1900 to 9 April 2015), and Chinese Biomedical Literature Database (CBM) (1978 to 9 April 2015).

SELECTION CRITERIA: We included all randomized controlled trials that compared abdominal drainage versus no drainage in patients undergoing pancreatic surgery. We also included randomized controlled trials that compared different types of drains and different schedules for drain removal in patients undergoing pancreatic surgery.

DATA COLLECTION AND ANALYSIS: Two review authors independently identified the trials for inclusion, collected the data, and assessed the risk of bias. We performed the meta-analyses using Review Manager 5. We calculated the risk ratio (RR) for dichotomous outcomes and the mean difference (MD) for continuous outcomes with 95% confidence intervals (CI). For all analyses, we employed the random-effects model.

MAIN RESULTS: Drain use versus no drain useWe included two trials involving 316 participants who were randomized to the drainage group (N = 156) and the no drainage group (N = 160) after pancreatic surgery. Both trials were at high risk of bias. There was inadequate evidence to establish the effect of drains on mortality at 30 days (drains 1.3%; no drains 3.8%; RR 0.44; 95% CI 0.05 to 3.94; two studies; very low-quality evidence), mortality at 90 days (2.9% versus 11.6%; RR 0.24; 95% CI 0.05 to 1.10; one study; very low-quality evidence), intra-abdominal infection (8.3% versus 14.4%; RR 0.61; 95% CI 0.25 to 1.46; two studies), wound infection (10.9% versus 11.9%; RR 0.91; 95% CI 0.45 to 1.86; two studies), morbidity (67.3% versus 65.0%; RR 1.02; 95% CI 0.88 to 1.19; two studies), length of hospital stay (MD -0.97 days; 95% CI -1.41 to -0.53; two studies), or additional open procedures for postoperative complications (6.3% versus 6.4%; RR 0.90, 95% CI 0.15 to 5.32; two studies). There was one drain-related complication in the drainage group (0.6%). The quality of evidence was low, or very low. Type of drainThere were no randomized controlled trials comparing one type of drain versus another. Early versus late drain removalWe included one trial involving 114 participants with a low risk of postoperative pancreatic fistula who were randomized to the early drain removal group (N = 57) and the late drain removal group (N = 57) after pancreatic surgery. The trial was at high risk of bias. There was no evidence of differences between the two groups in the mortality at 30 days (0% for both groups) or additional open procedures for postoperative complications (0% versus 1.8%; RR 0.33; 95% CI 0.01 to 8.01). The early drain removal group was associated with lower rates of postoperative complications (38.5% versus 61.4%; RR 0.63; 95% CI 0.43 to 0.93), shorter length of hospital stay (MD -2.10 days; 95% CI -4.17 to -0.03; 21.5% decrease of an 'average' length of hospital stay) and hospital costs (17.0% decrease of 'average' hospital costs) than in the late drain removal group. The quality of evidence for each of the outcomes was low.

AUTHORS' CONCLUSIONS: It is not clear whether routine abdominal drainage has any effect on the reduction of mortality and postoperative complications after pancreatic surgery. In case of drain insertion, low-quality evidence suggests that early removal may be superior to late removal for patients with low risk of postoperative pancreatic fistula.