Preoperative normetanephrine levels, but not doxazosin dose, predict intraoperative hemodynamic instability in pheochromocytoma surgery

Preoperative α-adrenergic blockade is routinely recommended before adrenalectomy for pheochromocytoma to reduce intraoperative hemodynamic instability. However, the need, intensity, and duration of preoperative blockade remain uncertain.

This single-center, retrospective study included adult patients who underwent adrenalectomy for pheochromocytoma at Karolinska University Hospital between 2014 and 2023. The association between preoperative doxazosin treatment, plasma metanephrine and normetanephrine concentrations, and intraoperative hemodynamic instability was evaluated. Correlation analysis and multivariable linear regression were performed.

Thirty-three patients were included (49% female; median age 59 years). Neither preoperative doxazosin dose nor treatment duration was associated with intraoperative systolic blood pressure reduction or intraoperative adenosine requirements. In contrast, higher preoperative metanephrine and normetanephrine concentrations were significantly associated with greater intraoperative vasoactive support requirements and a greater systolic blood pressure reduction after adrenal vein ligation. Tumor size showed a significant positive correlation with normetanephrine concentrations but was not independently associated with intraoperative hemodynamic instability. In multivariate analysis, preoperative normetanephrine concentration remained the only independent predictor of intraoperative reduction in systolic blood pressure after adrenal vein ligation.

Preoperative normetanephrine concentration is associated with intraoperative hemodynamic instability in pheochromocytoma surgery, whereas doxazosin dose and treatment duration were not. These findings suggest that biochemical tumor activity may be more clinically relevant than the intensity of preoperative α-blockade when assessing perioperative cardiovascular risk.