A 45-year-old woman comes to the office for preoperative evaluation. The patient had been having intermittent headaches and sweating for several months. During that time, plasma metanephrines were found to be markedly elevated, and she underwent an abdominal CT scan that showed a 4.9 cm left adrenal mass. She has no other medical problems and takes no medications. Family history is unremarkable. The patient does not use tobacco, alcohol, or illicit drugs. Blood pressure is 136/84 mm Hg and pulse is 92/min. Physical examination is normal. Surgical resection of the mass is scheduled in 2 weeks. Which of the following is the most appropriate next step in preparation for surgery?

Question

A 45-year-old woman comes to the office for preoperative evaluation.  The patient had been having intermittent headaches and sweating for several months.  During that time, plasma metanephrines were found to be markedly elevated, and she underwent an abdominal CT scan that showed a 4.9 cm left adrenal mass.  She has no other medical problems and takes no medications.  Family history is unremarkable.  The patient does not use tobacco, alcohol, or illicit drugs.  Blood pressure is 136/84 mm Hg and pulse is 92/min.  Physical examination is normal.  Surgical resection of the mass is scheduled in 2 weeks.  Which of the following is the most appropriate next step in preparation for surgery?

Quizplus · Accepted Answer

11ec25c8_d8ce_2cb1_bc81_7b6459ca4221_MD0003_00 An adrenal mass in combination with elevated plasma metanephrines is diagnostic of pheochromocytoma. All pheochromocytomas should undergo surgical resection due to the risk for complications caused by catecholamine surges and the potential for malignant disease (approximately 10% of pheochromocytomas are malignant). Surgical removal of a pheochromocytoma is a high-risk procedure because intraoperative catecholamine surges can precipitate hypertensive crisis, pheochromocytoma crisis (a condition characterized by labile blood pressures, high fever, and multiorgan failure), and fatal arrhythmias. To help prevent these complications, appropriate adrenergic blockade is needed prior to surgery. The order of administration of adrenergic blockade is critical. Beta-blocker therapy in the absence of alpha-adrenergic blockade can lead to lethal hypertensive crisis due to unopposed alpha-1 stimulation. Therefore, alpha-adrenergic blockade should be administered first, usually 7-14 days prior to surgery. Phenoxybenzamine, an irreversible and nonselective alpha blocker, is often preferred; however, selective alpha-1 blockers (eg, terazosin) are also sometimes used. Patients should also be encouraged to increase sodium intake and stay well-hydrated to minimize possible side effects of alpha-adrenergic blockade (eg, orthostasis, hypotension). Once adequate alpha-adrenergic blockade is established, beta-adrenergic blockade (eg, propranolol) can be safely initiated, usually 2-3 days prior to surgery (Choice D). (Choice A) Octreotide is a somatostatin analogue used in carcinoid syndrome (eg, diarrhea, flushing, elevated urinary 5-hydroxyindoleacetic acid). It has unclear effects on slowing the growth of malignant pheochromocytomas, which are histologically identical to benign pheochromocytomas but show evidence of metastasis or localized tissue invasion. (Choice C) Although ACE inhibitors may help reduce blood pressure, they will not help prevent beta-1 receptor-mediated cardiac effects (eg, tachycardia, arrhythmias). (Choice E) Pharmacologic intervention is necessary as this patient will be at high risk for serious intraoperative complications without adequate preoperative adrenergic blockade. Educational objective: All pheochromocytomas should undergo surgical resection, which is a high-risk procedure due to the potential for intraoperative catecholamine surges and related complications. To reduce this risk, patients should initiate preoperative alpha-adrenergic blockade 7-14 days prior to surgery, followed by beta-adrenergic blockade 2-3 days prior to surgery. Beta-blocker therapy should never be given in the absence of alpha blockade due to the risk of precipitating hypertensive crisis. References: Pheochromocytoma and paraganglioma: an endocrine society clinical practice guideline. (http://www.ncbi.nlm.nih.gov/pubmed/24893135)

A 45-Year-Old Woman Comes to the Office for Preoperative Evaluation