Preoperative Preparation for Pheochromocytoma Surgery
Patients with pheochromocytoma require alpha-adrenergic blockade for 10-14 days prior to surgery, followed by beta-blockade if tachycardia develops, along with aggressive volume expansion to prevent perioperative hypertensive crisis and cardiovascular complications. 1
Alpha-Adrenergic Blockade (First-Line)
Initiate alpha-blockade as the foundation of preoperative preparation:
- Start alpha-blockade 10-14 days before surgery to allow adequate time for blood pressure control and plasma volume restoration 1
- Phenoxybenzamine is the FDA-approved medication for pheochromocytoma, specifically indicated to control hypertensive episodes and sweating 2
- Doxazosin (selective alpha-1 blocker) is an alternative with fewer adverse effects and less postoperative hypotension compared to phenoxybenzamine 3, 4
- In a comparative study, doxazosin showed smoother intraoperative blood pressure control with only 2/85 patients experiencing radical blood pressure fluctuations versus 10/70 patients in the phenoxybenzamine group 3
Beta-Adrenergic Blockade (Second-Line, Never First)
Only add beta-blockade AFTER adequate alpha-blockade is established:
- Beta-blockers should never be started before alpha-blockade to avoid unopposed alpha-receptor stimulation causing severe hypertensive crisis 2, 1
- Initiate beta-blockade only if tachyarrhythmias develop during alpha-blockade 2, 1
Volume Expansion
Aggressive fluid resuscitation is essential:
- Restore blood volume to normal before surgery, as chronic catecholamine excess causes volume contraction 1
- Liberal preoperative hydration prevents severe postoperative hypotension that occurs when catecholamine levels suddenly drop after tumor removal 4
Preoperative Monitoring Requirements
Monitor these parameters to confirm adequate preparation:
- Blood pressure control with resolution of hypertensive episodes 1
- Heart rate and cardiac rhythm to detect arrhythmias requiring beta-blockade 1
- Assess for pheochromocytoma-induced cardiomyopathy, which exists to varying degrees in most patients and requires specific perioperative cardiac management beyond simple blood pressure control 5
Critical Pitfalls to Avoid
- Never start beta-blockers before alpha-blockade - this causes unopposed alpha-stimulation and potentially fatal hypertensive crisis 2, 1
- Inadequate duration of alpha-blockade (less than 10-14 days) increases risk of intraoperative hypertensive crisis 1
- Insufficient volume expansion leads to severe postoperative hypotension and cardiovascular collapse 4
- Failure to involve experienced anesthesiology - this surgery requires strict cooperation between cardiology, endocrinology, surgery, and anesthesiology teams 1
Surgical Approach Considerations
Minimally invasive surgery should be performed when feasible:
- Laparoscopic adrenalectomy is safe and effective for pheochromocytomas, even for tumors >6 cm in selected cases 6, 7
- Preoperative alpha-blockade does not completely prevent intraoperative hypertensive crises (occurring in 15% of cases), but facilitates pharmacological management and prevents major cardiovascular complications 7