<s>[INST] context: Causes of Paralytic ileus 
Postoperative - a degree of ileus usually occurs after any abdominal procedure and is self-limiting, with a variable duration of 24-72 hrs. Post op ileus may be prolonged in the presence of hypoproteinemia or metabolic abnormality.

Infection

Peritonitis
Intrabdominal abscess
Sepsis
Pneumonia

Electrolyte abnormalities

Uremia
Hypokalemia
Hyponatremia
Hypomagnesaemia
Hypermagnesemia

Medication

Anticholinergics
Opiates
Phenothiazines
Calcium channel blocker
Tricyclic antidepressants

Spinal cord injury

Retroperitoneal hemorrhage

Myocardial infarction
Mesenteric ischemia
Hypothyrodism
Ureteric colic


Paralytic ileus is a state in which there is failure of transmission of peristaltic waves secondary to neuromuscular failure.
The resultant stasis leads to accumulation of fluid and gas within the bowel with associated distention, vomiting, absent or diminished bowel sounds and absolute constipation.
Radiological picture shows dilated gas filled bowel loops with multiple air-fluid level.
The picture is similar to mechanical small bowel obstruction; the only differentiating point is presence of gas in colon and rectum in paralytic ileus.
Other clinical differentiating features of paralytic ileus from mechanical small bowel obstruction are.


Pain - Pain is colicky in mechanical obstruction. Pain is not a feature of paralytic ileus and if present is a steady, diffuse pain.
Bowel sounds - Bowel sounds are hypoactive or absent in paralytic ileus in contrast to hyperactive bowel sounds in mechanical obstruction. [/INST] question: Paralytic ileus is seen in -a) Spinal cord injuryb) Hypocalcemiac) Hypermagnesemiad) Uremia | options: A: b B: ad C: ac D: ab | answer: B </s>