Effect of neostigmine on integrity of ileorectal anastomoses

Patients undergoing total colectomy and ileorectal anastomosis for chronic ulcerative colitis were divided into two groups depending on whether neostigmine was administered during the anaesthetic to reverse the muscle relaxant. Those receiving neostigmine showed a postoperative anastomotic leakage rate of 36%. In the group not receiving neostigmine the leak rate was 4%, an apparently highly significant difference. Neostigmine may produce this effect by causing contractions of the gut musculature or by vasoconstriction of the blood vessels to the suture line, resulting in local ischaemia.