Preoperative Levels of Catecholamines and Metanephrines and Intraoperative Hemodynamics of Patients Undergoing Pheochromocytoma and Paraganglioma Resection

Objective To determine whether, despite pharmacologic adrenergic receptor blockade, higher preoperative levels of catecholamines and metanephrines (adrenergic activity) are associated with increased intraoperative complications. Materials and Methods Records of patients undergoing paraganglioma and pheochromocytoma (PGL-PCC) resection from January 1, 2000, to June 30, 2015, were reviewed for preoperative levels of adrenergic activity, intraoperative variability in blood pressure and heart rate (range), and postoperative outcomes (hypotension requiring treatment). Patients were categorized by maximum preoperative adrenergic activity by greater degree of abnormality, categorized as normal (≤100%) or 101%-200%, 201%-500%, 501%-1000%, and ≥1001% of upper limit of normal. Results In total, 258 patients underwent intrathoracic or intra-abdominal PGL-PCC resection, of whom 240 received pretreatment with nonselective α_1,2-blockers and 7 received pretreatment with selective α₁-blockers. Intraoperative hemodynamic variability was greater with higher preoperative levels of adrenergic activity (P <.001). However, substantial variability was observed even with adrenergic activity levels within the normal range: systolic blood pressure (median [interquartile range], 75 [63-83] mm Hg) and heart rate (34 [26-43] beats per minute). Among patients with preoperative levels of adrenergic activity ≤500% vs ≥501% of the upper limit of normal, higher levels were associated with greater likelihood of postoperative diagnosis of volume overload (8% vs 2%, P = .04) and greater requirement for vasopressor infusions for hypotension (5% vs 1%, P = .01). Conclusion Substantial intraoperative hemodynamic instability was encountered in patients with PGL-PCC resection, regardless of preoperative hormonal activity level; therefore, universal preoperative adrenergic receptor blockade should be recommended. Postoperative hypotension was rare and more prevalent in those with higher preoperative hormonal activity.