Phenoxybenzamine is no longer the standard agent used for alpha blockade before adrenalectomy for pheochromocytoma: A national study of 552 patients.

BACKGROUND

Phenoxybenzamine has been the standard agent for blockade before adrenalectomy for pheochromocytoma. However, high cost and limited availability have hampered its use. This study investigated whether other agents have supplanted the use of phenoxybenzamine as the first-line agent for alpha blockade in pheochromocytoma.

METHODS

We performed a retrospective analysis of patients in the IBM MarketScan Database who underwent adrenalectomy for pheochromocytoma (2008-2019). Patients were categorized as having been blocked with phenoxybenzamine, selective alpha blockers, calcium channel blockers and/or beta blockers, or none of the above. The outcomes included prescription costs, perioperative costs, and length of stay.

RESULTS

A total of 552 patients were identified; 58.7% were female, and the median age was 49 (interquartile range 40-57) years. In total, 291 (52.7%) patients were blocked with phenoxybenzamine, 114 (20.7%) with selective alpha blockers, 42 (7.6%) with only calcium channel blockers and/or beta blockers, and 76 (13.8%) with none. The proportion of patients blocked with phenoxybenzamine decreased from 71.0% in 2008 to 21.2% in 2019. The proportion of patients blocked with selective alpha blockers increased from 6.5% in 2008 to 42.4% and in 2019. The median cost of phenoxybenzamine increased from $722 (interquartile range $441-$1,514) in 2008 to $9,616 (interquartile range $5,049-$16,373) in 2019 (P < .001). Length of stay (2 [interquartile range 1-4] days vs 2 [interquartile range 0-3] days) and total perioperative costs ($24,250 [interquartile range $17,462-$33,849] vs $22,098 [interquartile range $16,341-$29,178] between phenoxybenzamine and selective alpha blocker groups were similar.

CONCLUSION

There has been a significant shift away from phenoxybenzamine for preoperative blockade before resection of pheochromocytoma. Selective alpha blockers and calcium channel blockers are increasingly used, likely due to reduced costs, without compromised length of stay or intensive care unit admission.