In 12 patients with phaeochromocytoma total blood volume (TBV) prior to and after treatment with phenoxybenzamine and the haemodynamic changes during surgery were determined. Our results were analysed with regard to the standard of our anaesthesiological management. The mean TBV was reduced in 6 of 12 patients. Great individual variations were found after treatment with phenoxybenzamine. In 6 patients alpha-blockade induced an increase of TBV (+ 10%), 2 patients showed no changes and 4 a decrease of TBV (-18%). Haemodynamic measurements prior to induction of anaesthesia revealed a reversal of catecholamine induced cardiovascular changes. During tumour manipulation the supply of vasodilatators not only prevented hypertensive crises but also induced a marked decrease of systemic vascular resistance. All patients received controlled volume loading until tumour removal, leading to progressive increase in pulmonary capillary wedge pressure and cardiac index. Hypotension or left ventricular failure never occurred. Thus, deep anaesthesia and continuous application of vasodilatators during tumour preparation are the main factors to prevent left ventricular failure from increased systemic vascular resistance and oxygen consumption.