Successful Management of Phaeochromocytoma using Preoperative Oral Labetalol and Intraoperative Magnesium Sulphate: Report of four cases.

Phaeochromocytoma is a rare neuroendocrine catecholamine-secreting tumour. This type of tumour poses multidimensional anaesthetic challenges as it has an unpredictable clinical course during surgical resection. The alpha-blocking agent phenoxybenzamine remained the mainstay in preoperative preparation before the introduction of beta-blocking agents. We report four cases operated between 2009-2012 at Sultan Qaboos University Hospital, Muscat, Oman. The cases were prepared with oral labetalol, as the alpha-blocking drug phenoxybenzamine was not immediately available. Responses to simulated stress were tested in the theatre before surgery. Anaesthesia was induced under invasive arterial pressure monitoring and magnesium sulphate infusion. Rare intraoperative surges in blood pressure during tumour manipulation were treated with sodium nitroprusside infusions and phentolamine boluses. All of the patients had an uneventful postoperative recovery. Preoperative treatment with labetalol has rarely been reported and can be considered as a potential therapeutic option with optimal patient monitoring if phenoxybenzamine is unavailable.