Signs and Symptoms of Acute Abdomen
Nausea / vomitting
Constipation / obstipation
Severe or complete constipation caused by obstruction.
Proximal SBO Symptoms
Proximal small bowel obstruction
- Vomitting is early and profuse
- Rapid dehydration
- Distension is minimal and not many fluid levels on imaging.
Distal SBO Symptoms
Distal small bowel obstruction
- Vomitting is often delayed
- Pain and central distension
- Multiple air/fluid levels on imaging
Large bowel obstruction
- Distension is early and pronounced
- Pain is less severe
- Vomitting and dehydration occur later
Pathophysiology of Bowel Obstruction
Distension causes decreased absorption, and then increased secretion.
Increased intraluminal pressure.
Compresison of venules, bowel wall edema, decreased inflow from capillaries, and ischemia.
Types of Mechanical Obstruction
2. Intrinsic bowel lesions
3. Lesions extrinsic to the bowel
Intraluminal Causes of Obstruction
1. Intussusception (the inversion of one portion of the intestine within another)
2. Gallstone ileus (gallstone gets lodged in the small intestine)
Intrinsic Bowel Lesions of Obstruction
Extrinsic Causes of Obstruction
1. Adhesions (scar tissue)
3. Volvulas (twisting of stomach or intestine)
Management for Complete Obstruction
Early surgery. Usually 12-24 hours be in surgery because of the high risk of strangulation (20-40%).
Management for Partial Obstruction
Much lower risk of strangulation, and many will resolve without operative intervention. These can wait and follow with observation.
Absolute Indication for Surgery
Progressive development of severe central abdominal pain.