Aim– To identify and analyse etiology, clinical presentation, treatment and outcome in patients with acute mechanical bowel obstruction with incidence of ischemia,gangrene and perforation.

Method–This is a prospective observational study of 120 patients of acute mechanical bowel obstruction admitted from 2014 to 2016.

Result–In consecutive 120 patients, adhesion 64 (53.3%), tuberculosis 22 (18.3%), appendicitis 9 (7.5%) and stricture 5 (4.17%) were most common etiology, absence of passage of flatus and motion 111 (92.5%), pain in abdomen 99 (82.5%), and abdominal distention 89 (74.1%) were most common clinical presentation, treatment modality used conservatively for 55 (45.8%) and operatively for 65 (54.2%).Incidence of ischemia 26 (21.6%), gangrene 05 (4.1%), and perforation 01(0.83%).

Conclusion–Absence of passage of flatus and/or feces, abdominal pain and abdominal distension are the most common symptoms and physical finding of patients with acute mechanical bowel obstruction, respectively. Adhesions, tuberculosis, appendicitis and stricture are the most common causes of obstruction, as well as of bowel ischemia, necrosis, and perforation. Although an important proportion of these patients require immediate operation, a substantial portion can be non–operatively treated. Great caution should be taken for the treatment of these patients since the incidence of bowel ischemia, necrosis, and perforation is significantly high.