Clinical diagnostics

Abdominal examination. Perform the examination in standard manner, i.e., inspection, auscultation, percussion, and palpation. LBO may be characterized by diminished or, in later stages, absent bowel sounds. The abdomen is distended and may be tender. The presence of true involuntary guarding or peritoneal signs should raise the specter of another intra-abdominal process, such as an abscess. The practice of seeking rebound tenderness is misleading and potentially cruel. Many patients without peritoneal signs complain vigorously after an aggressive rebound maneuver. Seeking tenderness and pain by having the patient cough or by shaking the bed probably is more useful.

Examination of inguinal and femoral regions. This should be an integral part of the examination. Incarcerated hernias represent a frequently missed cause of bowel obstruction. In particular, colonic obstruction often is caused by a left-sided inguinal hernia with the sigmoid colon incarcerated in the hernia.

Digital rectal examination. Perform this to verify the patency of the anus in a neonate. The examination focuses on identifying rectal pathology that may caus the obstruction and determining the contents of the rectal vault. Hard stools suggest impaction. Soft stools suggest obstipation. An empty vault suggests obstruction proximal to the level that the examining finger can reach. Faecal occult blood testing should be performed, and a positive result may suggest the possibility of a more proximal neoplasm.