Effect of phentolamine on the metabolic response to gynaecological surgery

The effect of the infusion of phentolamine 0.5 mg min-1 on the metabolic response to gynaecological surgery was investigated. In comparison with the control group of patients, phentolamine was associated with a significant increase in plasma insulin concentration after 30 and 60 min of surgery. The glycaemic response to surgery was decreased by alpha-adrenergic blockade, but this was only significant after 120 min of surgery. The hypotension produced by the administration of phentolamine was well tolerated.