The nurse assesses the client's blood pressure frequently. This is based on the knowledge that pheochromocytoma of the adrenal medulla releases excessive amounts of

• A. Renin
• B. Aldosterone
• C. Catecholamines
• D. Glucocorticoids

Answer: (C)

Pheochromocytoma of the adrenal medulla releases excessive catecholamines—epinephrine and norepinephrine. These hormones trigger rapid increases in heart rate and peripheral vascular resistance, producing marked, episodic hypertension. Because blood pressure can fluctuate dramatically and unpredictably with these tumors, frequent BP monitoring helps detect hypertensive crises, guides urgent management, and informs perioperative planning. The other substances listed aren’t produced in excess by pheochromocytoma: renin raises BP via the RAAS system but isn’t linked to adrenal medulla tumors; aldosterone increases sodium and water reabsorption; glucocorticoids affect metabolism and can influence BP in other contexts but don’t explain the characteristic episodic hypertension of pheochromocytoma.