| name | pheo-preoperative-alpha-blockade |
| description | Pre-operative preparation protocol for Pheochromocytoma, focusing on alpha-blockade titration and volume expansion. Trigger when a clinician asks "prep for pheo surgery", "alpha blockade vs beta blockade", or "doxazosin titration". |
Pheochromocytoma Pre-operative Alpha-Blockade
Standard preparation protocol to ensure cardiovascular stability during and after surgical resection of PPGL.
Step 1 — Initiate Alpha-Adrenergic Blockade
Start 7 to 14 days prior to surgery.
- Primary Agent:
- Phenoxybenzamine (Non-selective): Start 10 mg BD, titrate up by 10-20 mg every 2-3 days.
- Alternative: Doxazosin or Terazosin (Selective): Start 1-2 mg daily, titrate up to 10-16 mg daily.
- Goal of Titration:
- BP < 130/80 mmHg (sitting) and > 90 mmHg SBP (standing).
- Moderate orthostatic hypotension is a sign of achieved blockade.
Step 2 — Initiate Beta-Blockade (ONLY second)
Start only 2-3 days AFTER effective alpha-blockade is established.
- Indications: Tachycardia (HR > 100) or arrhythmias.
- Agents: Metoprolol, Atenolol, or Propranolol.
- Contraindication: NEVER start beta-blockade first (Unopposed Alpha-stimulation risk).
Step 3 — Volume Expansion
Start 2 days prior to surgery.
- Objective: Prevent post-resection hypotension.
- Action: High-sodium diet (>5000 mg/day) and increased fluid intake.
- Inpatient: 1-2 liters of normal saline overnight before surgery.
Clinical Guardrails
- ECG Monitoring: Essential during titration in patients with cardiac history.
- The Lakhani Rule: In elderly patients or those with coronary artery disease (like Mr. Mohan), titrate more slowly and target a less aggressive BP (e.g., 140/90).
Source: Lenders JW, et al. Pheochromocytoma and Paraganglioma: An Endocrine Society Clinical Practice Guideline. 2014.
