Cardiac and circulatory response to the intravenous administration of urapidil during general anaesthesia.

The authors have assessed the hypotensive response to the intravenous administration of urapidil bolus, during intra-operative hypertensive crises, in 42 patients undergoing general anaesthesia for surgery. Twenty-two of these patients underwent major vascular surgery and were monitored through catheters introduced into the radial and pulmonary arteries, to study the haemodynamic changes induced by urapidil. A significant reduction was observed in these values: systolic and diastolic arterial pressure, systolic and diastolic pulmonary pressure, pulmonary wedge pressure and systemic vascular resistance. A non-significant reduction was observed in central venous pressure and pulmonary vascular resistance. Heart rate and cardiac output remained unchanged. Systolic arterial pressure decreased 12% from the baseline in 81% of patients. The transient action of urapidil bolus in some cases (55%) suggests the need for urapidil infusion.