Efficacy and Safety of Neostigmine and Decompressive Colonoscopy for Acute Colonic Pseudo-Obstruction: A Single-Center Analysis

BACKGROUND: Acute colonic pseudo-obstruction (ACPO) is characterized by acute colonic dilation in the absence of anatomical obstruction. Neostigmine is an acetylcholinesterase inhibitor recommended as first-line salvage therapy for uncomplicated ACPO. Decompressive colonoscopy is recommended if neostigmine is contraindicated or unsuccessful. There is a need to better characterize relative efficacy and factors impacting treatment choice. The aim of the study was to examine the use, efficacy, and safety of neostigmine and decompressive colonoscopy in the management of ACPO at a single academic center. METHODS: Patients ≥ 18 years of age meeting established criteria for uncomplicated ACPO and with cecal diameter ≥ 10 cm on imaging between 1999 and 2019 were identified. Individuals were categorized as having received supportive care alone or subsequent trials of neostigmine or decompressive colonoscopy. Demographics and pre- and post-intervention data were collected, including indication and contraindication to intervention used, time to intervention, initial response, and adverse events. RESULTS: In 46 cases of ACPO (N = 42 patients), all but one individual received initial supportive care. Seven responded to conservative measures alone. Of the patients failing supportive care, 15 cases were initially treated with neostigmine (response rate 86.7%) and 24 initially underwent decompressive colonoscopy (response rate 95.8%) (P = 0.390). One episode of transient bradycardia, resolved with atropine, occurred in the neostigmine group. One patient experienced respiratory instability during colonoscopy. CONCLUSIONS: Both neostigmine and decompressive colonoscopy appear effective for treating uncomplicated ACPO in individuals failing conservative therapy. Adverse events were infrequent in both cohorts. Future prospective studies examining treatment for ACPO should focus on whether either intervention is superior to the other.