Ogilvie syndrome

Overview
Ogilvie syndrome is the acute pseudoobstruction and dilation of the colon in the absence of any mechanical obstruction in severely ill patients.

Colonic pseudo-obstruction is characterized by massive dilatation of the cecum (diameter > 10 cm) and right colon on abdominal X-ray.

Etiology
Recent surgery (most common following coronary artery bypass surgery), neurologic disorders, serious infections, cardiorespiratory insufficiency, metabolic disturbances, and drugs that disturb colonic motility (e.g., anticholinergics or narcotics) contribute to the development of this condition.

Pathophysiology
The exact mechanism behind the acute colonic pseudo-obstruction is not fully elucidated. The probable explanation is imbalance in the regulation of colonic motor activity by the autonomic nervous system.

Signs and symptoms
Usually the patient has abdominal distention, pain and altered bowel movements.

Treatment
It usually resolves with conservative therapy stopping oral ingestions, i.e. nil per os and a nasogastric tube, but may require colonoscopic decompression which is successful in 70% of the cases. A study published in the New England Journal of Medicine showed that neostigmine is a potent pharmacological way of decompressing the colon. According to the American Society for Gastrointestinal Endoscopy (ASGE), it should be considered prior to colonoscopic decompression. The use of neostigmine is not without risk since it can induce bradyarrhythmia and bronchospasms. Therefore atropine should be within immediate reach when this therapy is used.

Prognosis
It is a serious medical disorder and the mortality rate can be as high as 30%. The high mortality rate is likely a measure that this syndrome is seen in critically ill patients, rather than this syndrome being in itself lethal.