Peritoneal Lavage And Continuous Veno-venous Hemofiltration For Severe Acute Pancreatitis:a Systematic Review

Objectives To assess the efficiency and safety of peritoneal lavage in patients with severe acute pancreatitis.Methods A comprehensive search was performed to identify randomized controlled trials comparing peritoneal lavage with conservative treatment for severe acute pancreatitis. The primary outcome was all-cause mortality. Secondary outcomes included complications rate, proportion of need for operation, length of hospital stay and so on.We conduted our review following the recommendations of the Cochrane handbook.We considered the methodological quality of the trials according to the 6 domains based on the Cochrane handbook and the Cochrane hepato-biliary group molude.Only the trials with adequate description of all the domains were assessed as low risk of bias.We measured the effect using risk ratio with 95% confidence interval.We used the I square stastisc to assess heterogeneity.For meta- analysis we used fixed effect model and random effect model according to the I square statistic.We performed trials sequential analysis to reduce the risk of random errors.Results A total of 962 patients from sixteen studies were subjected to meta-analysis. Peritoneal lavage did significantly decrease the mortality(Relative risk, 0.47; 95% confidence interval, 0.34-0.66; P < 0.01), with low heterogeneity among the studies(I2 = 7%; P = 0.38). Peritoneal lavage also appeared to significantly alter any of the other metaanalysis end points.Conclusions Although this systematic review indicate that there is statistically significant evidence of effect for continuous peritoneal lavage in severe acute pancreatitis in terms of mortality, complications rate, proportion of need for operation, length of hospital stay, and medical costs, at present there is no strong evidence to recommend any of continuous peritoneal lavage for treatment of severe acute pancreatitis, due to the general high risk of bias in these trials. One potential limitation of this systematic review is the various diagnostic criteria of severe acute pancreatitis used among studies. These studies included a mixed group of patients with both sterile and infected pancreatic necrosis. Additionally, the effect of peritoneal lavage may be influenced by the heterogeneity in drain size, location and number of drains placed, dosage, timing, and duration of administration. Another potential limitation of this systematic is the methodological quality of the included studies. They provided only limited descriptions of random sequence generation, allocation concealment, incomplete outcome data, selective reporting, and other risks of bias. It is well known that trials that are poorly designed methodologically show larger differences compared with rigorously conducted trials. Finally, we conducted comprehensive searches and tried to avoid publication bias, but most of the studies were published in Chinese, and are relatively small number of included studies may reduce the statistical power for these tests.