**Question:** The vessel which needs to be ligated in a patient with a bleeding peptic ulcer is:

A. Artery
B. Vein
C. Capillary
D. Posterior tributary of the mucosal arcade

**Core Concept:** Peptic ulcer is an ulcerated lesion in the lining of the stomach or duodenum caused by the interaction of various factors, including bacterial infections (H. pylori) and long-term use of nonsteroidal anti-inflammatory drugs (NSAIDs). Bleeding peptic ulcers can be life-threatening and require urgent management.

**Core Concept:** In the context of bleeding peptic ulcer, the vessel that needs to be ligated refers to a specific type of blood vessel that is actively bleeding or at high risk of bleeding.

**Why the Correct Answer is Right:** In the setting of a bleeding peptic ulcer, the correct answer, D (posterior tributary of the mucosal arcade), refers to the vessel that supplies blood to the ulcer base and is responsible for bleeding. Ligation of this vessel will effectively stop the bleeding.

**Why Each Wrong Option is Incorrect:**

A. Artery: Although arteries carry oxygenated blood, they are not the primary target for ligation in a bleeding peptic ulcer. Instead, ligation of the posterior tributary of the mucosal arcade (Option D) is more effective in controlling ulcer bleeding.

B. Vein: Veins carry deoxygenated blood and are not the primary target for ligation in a bleeding peptic ulcer.

C. Capillary: Capillaries are the smallest blood vessels, and ligation of these would be ineffective in controlling bleeding from a peptic ulcer. Ligation of the posterior tributary of the mucosal arcade (Option D) is more appropriate for treating bleeding peptic ulcers.

**Clinical Pearl:** In the management of bleeding peptic ulcers, identifying the specific vessel responsible for bleeding, such as the posterior tributary of the mucosal arcade, is crucial for effective treatment. Ligation of the correct vessel, in this case, D, will halt the bleeding and prevent further complications.