Question

A 35-year-old man diagnosed with pheochromocytoma is scheduled for surgery. Which medication should be given as preoperative preparation?

• A. Clonidine
• B. Phenoxybenzamine
• C. Esmolol
• D. Aspirin

Hint:

Pheochromocytoma surgery preparation: alpha blockade first with phenoxybenzamine, then beta blockade if needed.

Answer 1

The Correct Option is B

Step 1: Understanding the Question:
Pheochromocytoma is a catecholamine-secreting tumor of the adrenal medulla. Surgery is the definitive cure, but intraoperative tumor handling can cause massive catecholamine release and a fatal hypertensive crisis if the patient is not prepared.
Step 2: Detailed Explanation:

The Golden Rule: Preoperative preparation requires "Alpha blockade before Beta blockade." Alpha-blockers prevent severe hypertension.

Phenoxybenzamine: This is a non-selective, long-acting, irreversible alpha-adrenergic antagonist. It is traditionally the drug of choice for preoperative stabilization. It is started 10-14 days before surgery.

Mechanism of Benefit: It controls blood pressure and, more importantly, allows for the expansion of the intravascular volume, which is chronically contracted due to high sympathetic tone.

Beta-blockers (Esmolol): These are only added AFTER adequate alpha blockade has been achieved, and only if the patient has significant tachycardia. Giving a beta-blocker alone can lead to "unopposed alpha stimulation," causing a massive spike in BP.

Other options: Clonidine is a central alpha-2 agonist used for mild HTN but not standard for Pheo prep. Aspirin has no role here.

Step 3: Final Answer:
Phenoxybenzamine is the standard first-line alpha-blocker used to prepare patients for the safe resection of a pheochromocytoma.