A 45-year-old man with a history of previous right hemicolectomy for colon cancer presents with colicky abdominal pain which has become constant over the last few hours. He has marked abdominal distension and has had only minimal vomiting of a feculent material. His abdomen is diffusely tender. Abdominal x-ray shows multiple air fluid levels with dilatation of some loops to greater than 3 cm in diameter. The most likely diagnosis is:
A.	Proximal small bowel obstruction
B.	Distal small bowel obstruction
C.	Acute appendicitis
D.	Closed-loop small bowel obstruction
Answer:B
A 45-year-old man with a history of previous right hemicolectomy for colon cancer presents with colicky abdominal pain which has become constant over the last few hours. He has marked abdominal distension and has had only minimal vomiting of a feculent material. His abdomen is diffusely tender. Abdominal x-ray shows multiple air fluid levels with dilatation of some loops to greater than 3 cm in diameter. The most likely diagnosis is:
A.	Proximal small bowel obstruction B.	Distal small bowel obstruction C.	Acute appendicitis D.	Closed-loop small bowel obstruction