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: For the initial version of this review, 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). For this updated review, we searched the Cochrane Library, MEDLINE, Embase, Science Citation Index Expanded, and CBM from 2015 to 28 August 2016.

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

DATA COLLECTION AND ANALYSIS: We identified five trials (of 985 participants) which met our inclusion criteria. 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 three trials involving 711 participants who were randomized to the drainage group (N = 358) and the no drainage group (N = 353) after pancreatic surgery. There was inadequate evidence to establish the effect of drains on mortality at 30 days (2.2% with drains versus 3.4% no drains; RR 0.78, 95% CI 0.31 to 1.99; three studies; low-quality evidence), mortality at 90 days (2.9% versus 11.6%; RR 0.24, 95% CI 0.05 to 1.10; one study; low-quality evidence), intra-abdominal infection (7.3% versus 8.5%; RR 0.89, 95% CI 0.36 to 2.20; three studies; very low-quality evidence), wound infection (12.3% versus 13.3%; RR 0.92, 95% CI 0.63 to 1.36; three studies; low-quality evidence), morbidity (64.8% versus 62.0%; RR 1.04, 95% CI 0.93 to 1.16; three studies; moderate-quality evidence), length of hospital stay (MD -0.66 days, 95% CI -1.60 to 0.29; three studies; moderate-quality evidence), or additional open procedures for postoperative complications (11.5% versus 9.1%; RR 1.18, 95% CI 0.55 to 2.52; three studies). There was one drain-related complication in the drainage group (0.6%). Type of drainWe included one trial involving 160 participants who were randomized to the active drain group (N = 82) and the passive drain group (N = 78) after pancreatic surgery. There was no evidence of differences between the two groups in mortality at 30 days (1.2% with active drain versus 0% with passive drain), intra-abdominal infection (0% versus 2.6%), wound infection (6.1% versus 9.0%; RR 0.68, 95% CI 0.23 to 2.05), morbidity (22.0% versus 32.1%; RR 0.68, 95% CI 0.41 to 1.15), or additional open procedures for postoperative complications (1.2% versus 7.7%; RR 0.16, 95% CI 0.02 to 1.29). The active drain group was associated with shorter length of hospital stay (MD -1.90 days, 95% CI -3.67 to -0.13; 14.1% decrease of an 'average' length of hospital stay) than in the passive drain group. The quality of evidence was low, or very low. 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. There was no evidence of differences between the two groups in mortality at 30 days (0% for both groups) or additional open procedures for postoperative complications (0% with early drain removal versus 1.8% with late drain removal; 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 unclear 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 active drainage may reduce hospital stay after pancreatic surgery, and early removal may be superior to late removal for people with low risk of postoperative pancreatic fistula.