**Question:** All are complications of ileal resection, except:

A. Volvulus
B. Nutritional deficiencies
C. Anastomotic leak
D. Ileus

**Core Concept:** Ileal resection is a surgical procedure where a segment of the ileum is removed due to injury, disease, or other reasons. The complications related to this procedure can be broadly categorized into mechanical, ischemic, and infectious complications.

**Why the Correct Answer is Right:**

Option A: Volvulus (also known as volvulus) is a condition where the bowel twists on itself, leading to ischemia and potential necrosis. Although it can occur after ileal resection, it is not a complication of the resection itself. Instead, it is a complication of the procedure's anatomical changes altering the bowel's natural mobility.

Option B: Nutritional deficiencies are a result of malabsorption due to the loss of absorptive surface area or dysfunctional absorption after an ileal resection. This is a complication of the surgery, not unrelated to it.

Option C: Anastomotic leak is a complication that occurs when the newly formed anastomosis (connection) between the remaining bowel segments fails, leading to peritonitis, sepsis, and potential mortality. This is a direct consequence of the ileal resection, making it a complication of the procedure.

Option D: Ileus is a mechanical obstruction of the bowel caused by spasm or paralysis of the bowel wall. It can occur after ileal resection due to the surgical trauma or anesthesia. While it is related to the surgery, it is not specific to ileal resection, and can occur after any gastrointestinal surgery.

**Why Each Wrong Option is Incorrect:**

Option A (Volvulus): Volvulus is a complication of anatomic change, not directly related to ileal resection.

Option B (Nutritional deficiencies): Nutritional deficiencies are a direct consequence of the loss of absorptive surface area due to the resection, making it a complication of the surgery.

Option C (Anastomotic leak): Anastomotic leak is a complication of the surgical intervention, specifically caused by the connection between the remaining bowel segments.

Option D (Ileus): Ileus is a mechanical obstruction of the bowel, which can be caused by surgical trauma or anesthesia, but it is not specific to ileal resection and can occur after any gastrointestinal surgery.

**Clinical Pearl:** Ileal resection is a surgical procedure to remove a segment of the ileum due to injury or disease. The complications associated with this procedure include anastomotic leak, nutritional deficiencies, and mechanical bowel obstruction (ileus). These complications are either directly related to the surgical procedure (anastomotic leak) or are consequences of the surgical intervention (nutritional deficiencies and ileus).