Obstruction of the small intestines

Complete proximal obstruction
-vomiting
-abdominal discomfort
-abnormal oral contrast x-rays or CT scan
Complete mid or distal obstruction
-colicky abdominal pain
-vomiting
-abdominal distention
-constipation-obstipation
-peristaltic rushes
-dilated small bowel on x-ray
-transition point on CT scan

Mechanical obstruction may be complete or partial. Simple obstruction occludes the lumen only. Strangulation obstruction impairs the blood also and leads to necrosis of the intestinal wall. Paralytic ileus / adynamic ileus, a disorder in which there is neurogenic failure of peristalsis to propel intestinal contents but no mechanical obstruction.
Etiology
1. Adhesions- from abdominal operations or inflammation, congenital bands
2. Neoplasms-particularly near the ileocecal valve
3. Hernia
4. Intussusception- invagination of one loop of intestine into another is rarely encountered in adults and is usually caused by a polyp or other intraluminal lesion .
5. Volvulus- results from rotation of bowel loops about a fixed point.
6. Foreign bodies
7. Gallstone ileus
8. Inflammatory bowel disease
9. Stricture
10. Cystic fibrosis
11. Hematoma

Swallowed air is the major source of gaseous distention because nitrogen is not well absorbed by mucosa. Bacterial fermentation produces gas too. Fluid fills the lumen proximal to the obstruction, because the bidirectional flux of salt and water is disrupted and net secretion is enhanced.
A. Simple obstruction
- presenting as profuse vomiting that seldom becomes feculent even in prolonged obstruction.
-upper abdominal pain/cramping periumbilical recurs every few minutes.
-vital sign may be normal
-dehydration
-abdominal distention is minimal to absent in proximal obstruction .
-peristalsis may be visible beneath the abdominal wall in thin patients .
-peristaltic rushes ,gurgles, and high-pitched tinkles are audible in coordination with attacks of cramping pain in distal obstruction.
-rectal examination is usually normal.
Laboratory:
-early stages may be normal
-there are hemoconcentration, leukocytosis, serum amylase, electrolyte abnormalities.
Imaging:
-supine and upright plain abdominal : a ladder like pattern, air-fluid levels. It May be minimal or absent in early obstruction .
-opaque Gallstones and air in the biliary tree should be looked for.
B. Strangulation obstruction
-shock that appears early in the course of obstruction suggests a strangulated closed loop.
-high fever may develop
-cramping abdominal pain become a severe countinuous ache.
-vomitus may contain gross or occult blood
Laboratory :
-Marked leukocytosis
-lactic acidosis does not resolve with volume resuscitation.
Imaging:
-intraperitoneal fluid
-loss of mucosal pattern.
Treatment :
1. Nasogastric suction/tube- to relieve vomiting, avoid aspiration, reduce abdominal distention.
2. Fluid and electrolyte resuscitation
-should begin with isotonic saline solution.
-not undergo operation until hypokalemia has been treated.
3. Antibiotics should be given
4. Required plasma or blood
5. Operation
-the patient has been rehydrated and vital organs are functioning satisfactorily.