Acute Colonic Pseudo-obstruction With Pneumatosis: Neostigmine May Still Be an Option!

Abstract

Case Presentation: A 35 year old female who underwent a robotic TAH/BSO for cervical cancer developed abdominal pain, bloating and obstipation on post-operative day (POD) #2. KUB revealed a pan-dilated colon with a cecum of 11 cm. GI was consulted on POD#5 due to a failure of conservative management. Examination revealed a distended, tense abdomen without bowel sounds. CT revealed pan-colonic dilation with a cecum of 9 cm with cecal pneumatosis. Acute colonic pseudo-obstruction (ACPO) and possible ischemia was diagnosed. After much deliberation regarding surgical vs. medical management, two doses of neostigmine within a 24 hour period were administered with complete resolution. Discussion: ACPO is a rare condition with unclear incidence. Risks include infection, surgery, narcotic use, and electrolyte imbalance. Symptoms include abdominal pain, distention, nausea, and vomiting. Mortality is increased with a cecum greater than 14 cm and time to decompression greater than 7 days. Treatment options vary from supportive, pharmacologic, endoscopic, and surgical therapies. Neostigmine, a reversible acetylcholinesterase inhibitor which stimulates muscarinic parasympathetic receptors to increase transit time, is effective in up to 91%, with a relapse of 38%. Colonoscopy with decompression tube is successful in up to 88%, carries a perforation risk of about 3% with a 1% mortality. Surgical intervention is associated with a 44% mortality in the setting of ischemia. Pneumatosis has long been associated with colonic ischemia. Recent radiologic research has increased our understanding of pneumatosis. No studies have looked at pneumatosis and psuedo-obstruction. Three patterns of pneumatosis have been described: Bubble like in idiopathic cases [our patient], linear type in conditions secondary to a pathologic etiology, and circular type in pulmonary disease. Conclusion: Our patient who had ACPO with bubbly type pneumatosis was effectively treated with neostigmine in efforts to avoid the risks associated with endoscopic and surgical procedures. Favorable indicators were bubbly type pneumatosis, lack of peritoneal signs, stable vital signs and a lack of acidosis. This is the first reported case of ACPO with pneumatosis safely treated with repeat administration of Neostigmine. We recommend consideration of neostigmine in select cases for ACPO with pneumatosis with favorable indicators in the hopes of decreasing morbidity and mortality from invasive procedures.Figure: KUB showing pan-dilated colon.Figure: CT Scan showing pneumatosis in the right colon and cecum.