[Use of ketanserin in anesthesia. A selective S2 serotonin receptor antagonist]

Serotonin is a vasoactive amine. It is formed in the chromaffin cells in the small intestine and is inactivated in the liver and lungs. The remainder is taken up in the thrombocytes so that only minimal quantities are found free in the plasma. The peripheral effect of serotonin occurs probably exclusively by means of a release of amine from the thrombocytes following local aggregation of these. Serotonin is thought to play a pathogenetic role in both systemic and pulmonary hypertension. Ketanserin is a serotonin antagonist with alpha-blocking effect. It reduces the blood pressure by reducing the peripheral vascular resistance without causing reflex tachycardia or fall in the minute volume of the heart. In the field of anaesthesiology, it may be employed in per- and postoperative hypertension but on account of the peripheral vasodilating effect it may also be employed in other conditions with peripheral vasoconstriction. Ketanserin has a moderate effect in cases of acutely developed pulmonary hypertension.