Meta-analysis of peritoneal lavage in appendicectomy

The use of peritoneal lavage to prevent postoperative intra-abdominal abscess (IAA) after appendicectomy has been debated widely.

A systematic review and meta-analysis of suction alone versus lavage for appendicitis was performed to determine the relative benefit of lavage. Primary outcomes were postoperative IAA and wound infection (WI). Inclusion criteria were human studies reporting a comparison of appendicectomy with or without peritoneal lavage.

Eight studies met the inclusion criteria, the majority of which were retrospective. Only three were RCTs. Four studies included analysis only of the paediatric population. The rate of IAA was 1·0-19·5 per cent in patients receiving suction alone and 1·5-18·6 per cent in those having lavage. WI rates were 1·0-29·2 per cent for suction alone and 0·8-20·5 per cent for lavage. The pooled risk difference for IAA was 0·01 (95 per cent c.i. -0·03 to 0·06; P = 0·50) and that for WI was 0·00 (-0·05 to 0·05; P = 0·98). Analyses of both outcomes indicated a medium degree of heterogeneity between effect estimates with I ² values of 71 per cent (P = 0·001) and 70 per cent (P = 0·010) for IAA and WI respectively.

There is no evidence of benefit of lavage over suction for postoperative infective complications, and no individual study demonstrated a significant benefit in patients receiving lavage.