Neostigmine - Safe and effective treatment for acute colonic pseudo-obstruction

BACKGROUND: Ogilvie's syndrome, or acute colonic pseudo-obstruction, is a c ommon and relatively dangerous condition. Lf left untreated, it may cause i schemic necrosis and colonic perforation, with a mortality rate as high as 50 percent. Neostigmine enhances excitatory parasympathetic activity by com peting with acetylcholine for attachment to acetylcholinesterase at sites o f cholinergic transmission and enhancing cholinergic action. We hypothesize d that neostigmine would restore peristalsis in patients with acute colonic pseudo-obstruction. METHODS: Twenty-eight patients at Fletcher Alien Healt h Care and The Cleveland Clinic Foundation were treated for acute colonic p seudoobstruction with neostigmine 2.5 mg IV over 3 minutes while being moni tored with telemetry. Mechanical obstruction had been excluded. RESULTS: Co mplete clinical resolution of large bowel distention occurred in 26 of the 28 patients. Time to pass flatus varied from 30 seconds to 10 minutes after administration of neostigmine. No adverse effects or complications were no ted. Of the two patients who did not resolve, one had a sigmoid cancer that required resection and one patient died from multiorgan failure. CONCLUSIO N: This study supports the theory that acute colonic pseudo-obstruction is the result of excessive parasympathetic suppression rather than sympathetic overactivity. We have shown that neostigmine is a safe and effective treat ment for acute colonic pseudo-obstruction.