What is the Special Anaesthetic Management for patients with Phaeochromocytoma?
Alpha-blockade (blocking of alpha-adrenergic receptors with drugs) and restoration of intravascular volume will substantially reduce perioperative complications.
Treatment of tachycardia and other arrhythmias with b-blockade should only be given after alpha-blockade as it may worsen the hypertension. The management can be divided up into preoperative, intraoperative and postoperative.
Preoperative Management
- alpha-Blockade (phenoxybenzamine) is given to maintain blood pressure below 180/90mmHg for at least 24hours before surgery.
- Re-expansion of plasma volume by using intravenous fluids after a-blockade.
- beta-Blockade for treatment of arrhythmias and tachycardias.
- Metyrosine is given to patients with metastatic disease or patients with severe symptoms. (This drug inhibits catecholamine synthesis).
Intraoperative Management
- Great caution should be taken when using drugs that may evoke a pressor response. A list of these drugs is shown below:
- Drugs that induce histamine release (e.g. morphine)
- Drugs that interact with catecholamines.
- Sympathomimetic agents.
- Indirectly acting sympathomimetic agents.
- Haemodynamic management:
- alpha-blockade for immediate treatment of hypertension.
- beta-blockade for immediate treatment of arrhythmias.
- 2 large-bore intravenous cannulas should be inserted for rapid access
Postoperative Management
1. Careful blood and fluid management.
2. When a bilateral adrenalectomy has been performed, steroid replacement is necessary.