208 Neostigmine to Treat Colonic Pseudo-Obstruction in Cancer Patients

Abstract

INTRODUCTION: Acute colonic pseudo-obstruction, or Ogilvie's syndrome, usually develops in patients post-operatively or during severe illness. It is defined as massive dilation of the colon without mechanical obstruction. Ogilvie's may resolve with conservative management, but frequently colonic decompression is needed to prevent bowel injury. Neostigmine is a drug used to treat Ogilvie's that can be tried prior to endoscopic decompression. It is a reversible acetylcholinesterase inhibitor, enhancing colonic motor activity. We aim to evaluate the demographics and clinical history of patients with Ogilvie's and the efficacy of neostigmine administration in treating Ogilvie's in our cancer population. METHODS: Retrospective data analysis was performed on patients from 2000 to 2018 who had colonic dilation, defined as >8 cm in part of the colon on x-ray or cross-sectional imaging, and received neostigmine. RESULTS: The total number of patients in the study was 29. The mean age of patients was 66.7 years old (range: age 46.5–81.0). Of the 29 patients, 5 patients were female (17.2%). Leukemia was the primary malignancy in 10 patients (34.5%) and solid tumor in the other 19 patients (65.5%). Metastatic disease was found in 15 patients (51.7%). Recent chemotherapy was administered to 21 patients (72.4%). The average number of hospitalization days was 34.7 days (range: 2–120 days). Pan-dilation of the colon was noted in 10 patients (34.5%) and cecal dilation alone was noted in 7 patients (24.1%). The mean diameter of dilated colon segment was 10.8 cm (range 8.0–15.0 cm). Post-operative Ogilvie's was noted in 5 patients (17.2%). Active infection was identified in 18 patients (64.2%). One dose of neostigmine was required in 20 patients (71.4%) and remaining patients required 2 or 3 doses. Improvement of Ogilvie's was noted in 23 patients (79.3%) and complete resolution in 13 patients (44.8%). Colonoscopy was needed after a trial of neostigmine in 10 patients (34.5%). Bradycardia due to neostigmine was noted in 3 patients (10.3%) without other complications noted. CONCLUSION: In our study evaluating cancer patient, Ogilvie's was more common in elderly male patients with solid tumors and active infection. Metastatic disease was noted in about half of the study patients. It was most common to have pan-colonic dilation and isolated cecal dilation. Administration of neostigmine led to improvement of colonic pseudo-obstruction in the majority of patients (79.3%) with complete resolution noted in 44.8% of patients.