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Updated: Feb 6, 2026

Synthesis and Microdiffraction at Extreme Pressures and Temperatures
Published on: October 7, 2013
Extreme and Cyclical Blood Pressure Elevation in a Pheochromocytoma Hypertensive Crisis
V Larouche1, N Garfield2, E Mitmaker3
1Adult Endocrinology and Metabolism Training Program, McGill University, Montréal, QC, Canada.
Abstract:
Pheochromocytomas are rare adrenal neoplasms characterized by excess secretion of catecholamines. We describe the case of a 65-year-old man, known for hypertension, with no family history of hereditary pheochromocytoma syndromes. He reported a two-year history of flushing, systolic blood pressure surges to 200 mmHg, headaches, tremors, and syncope. His initial workup revealed elevated 24h urine catecholamines and metanephrines. An adrenal MRI in March 2017 showed a large 7.6 cm heterogeneous right adrenal lesion. Given orthostatic hypotension, his final preoperative dose was limited to a low dose of terazosin and metoprolol. In the operating room, shortly after intubation and Foley insertion, his blood pressure rose to 350 mmHg. Surgery was cancelled and he was admitted to the intensive care unit, where intravenous phentolamine, nitroprusside, and nicardipine were started. His systolic blood pressure would oscillate between 60 mmHg and 350 mmHg at 2-3 minutes' intervals. After 3 days, he was weaned off intravenous medications. His oral medications were uptitrated to high doses of phenoxybenzamine, metoprolol, and nifedipine. Three weeks later, he underwent successful open right adrenalectomy. This case outlines the importance of preoperative preparation of pheochromocytomas and raises the question if phenoxybenzamine is the alpha-blocker of choice for larger tumours with significant hormonal secretion.
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