Phenoxybenzamine and doxazosin are equally effective in pretreating patients undergoing resection of a pheochromocytoma (PCC), researchers reported here at the 2018 Annual Meeting of The Endocrine Society (ENDO).
The administration of alpha-adrenergic receptor antagonists is recommended before PCC resection in order to prevent any perioperative cardiovascular complication.
For the current study, Edward Buitenwerf, MD, University of Groningen, Groningen, the Netherlands, and colleagues randomised patients aged older than 18 years with a benign PCC to pretreatment with penoxybenzamine or doxazosin.
Preoperative blood pressure targets were <130/80 mm Hg (supine) and systolic BP 90-110 mm Hg (upright). Beta-blockers were added if the heart rate was >80/min (supine) or >100/min (upright).
The primary endpoint was the percentage of intraoperative time outside of the blood pressure target range.
Of the 134 patients in the study 68 were pretreated with doxazosin and 66 with penoxybenzamine.
Results showed no difference in intraoperative time outside the blood pressure target range between the 2 groups (12% in the doxazosin group and 11% in the penoxybenzamine group).
Patients pretreated with doxazosin required fewer beta-blockers preoperatively than patients in the penoxybenzamine group (66% vs 89%), suggesting there was more preoperative reflex tachycardia in the penoxybenzamine group.
However, they also found that patients pretreated with penoxybenzamine needed fewer vasodilating agents during surgery than the doxazosin group, demonstrating that penoxybenzamine was more effective in preventing intraoperative hypertension.
There was no difference in postoperative hypertension between the 2 groups, as well as no difference in cardiovascular morbidity and mortality.