**Question:** A 68-year-old man presents for repair of an abdominal aortic aneurysm. Severe complicated atherosclerosis is noted at surgery, prompting concern for embolism of atheromatous material to the kidneys and other organs. If the patient were to develop a renal colonic infarct as a result of surgery, which of the following would be the most likely outcome?

A. Increased risk of post-operative infection
B. Increased risk of post-operative renal failure
C. Increased risk of post-operative gastrointestinal bleeding
D. Increased risk of post-operative respiratory failure

**Core Concept:** Atherosclerosis is a degenerative process involving the accumulation of fatty substances, mainly cholesterol and calcium, within the arterial walls, leading to narrowing and hardening of the arteries. In this scenario, the patient has severe complicated atherosclerosis, which increases the risk of embolization of atheromatous material to various organs, including the kidneys and colon.

**Why the Correct Answer is Right:**

If the patient develops a renal colonic infarct due to embolization of atheromatous material during abdominal aortic aneurysm repair, the most likely outcome would be **B. Increased risk of post-operative renal failure**.

The involvement of the renal artery by embolization can lead to a reduction in blood flow to the kidneys, causing tissue hypoxia and subsequent cell death (necrosis). This results in impaired renal function and organ failure, which is captured by the correct answer of increased risk of post-operative renal failure.

**Why Each Wrong Option is Incorrect:**

A. Increased risk of post-operative infection (Option A) is incorrect because the focus of surgery is on the abdominal aortic aneurysm, and the risk of infection is related to the procedure itself rather than the atheromatous embolization.

C. Increased risk of post-operative gastrointestinal bleeding (Option C) is incorrect because the focus of surgery is on the abdominal aortic aneurysm, and the risk of gastrointestinal bleeding is related to the surgical procedure rather than atheromatous embolization.

D. Increased risk of post-operative respiratory failure (Option D) is incorrect because the focus of surgery is on the abdominal aortic aneurysm, and the risk of respiratory failure is related to the surgical procedure rather than atheromatous embolization.

**Explanation of Embolization Mechanism:**

Embolization of atheromatous material can occur during the surgical procedure, especially in patients with severe atherosclerosis, as in this case. Atheromatous embolization can result in occlusion of small blood vessels supplying vital organs, leading to ischemia, infarction, and potential organ dysfunction. In this scenario, atheromatous material embolizes to the kidneys, causing renal ischemia, which can lead to acute kidney injury (AKI) and subsequent renal failure if not treated promptly.

**Clinical Pearls:**

1. Atherosclerosis is a common cause of peripheral artery disease, which can lead to embolization of atheromatous material to vital organs.
2. AKI, caused by