Acute Intestinal Pseudo-obstruction.

Acute pseudo-obstruction may manifest clinically in one of three forms--acute gastroparesis, ileus, and acute colonic pseudo-obstruction (Ogilvie's syndrome). Though formerly associated primarily with the postoperative state, these entities are increasingly recognized in association with a wide variety of major medical problems. There are few controlled studies to guide the clinician in the management of these disorders. Treatment remains largely empirical, and time-honored, based primarily on "bowel rest," nasogastric decompression, and supportive care. While a wide variety of pharmacologic approaches have been advocated, few have been subjected to, or survived, the rigors of a properly controlled trial. Neostigmine is a notable exception, and has been shown to be effective in Ogilvie's syndrome. Perforation is a significant threat in megacolon; colonoscopic, or surgical decompression may, therefore, be indicated. Both are associated with significant risks in this context, but may prevent progression to perforation with its attendant mortality. New approaches seek to exploit current concepts in the pathophysiology of ileus and megacolon but have not, as yet, achieved efficacy in human studies.