The role of isosorbide dinitrate in the treatment of perioperative hypertension.

Intravenous nitroglycerin (NTG) has recently been found to be useful for the control of blood pressure during the perioperative period, especially during coronary artery bypass procedures. The objective of this study was to determine whether intravenous isosorbide dinitrate (ISDN) could play a similar role. Sixty-seven patients undergoing coronary artery bypass grafting at three centers were randomly assigned to an ISDN or NTG treatment group. The hemodynamic performance of all patients was assessed by the methods commonly used for cardiac patients (ECG, arterial line, thermodilution pulmonary artery catheter). One of the two nitrates was infused whenever the systolic blood pressure or the pulmonary capillary wedge pressure exceeded predetermined values. Treatment by either agent was considered successful if the elevated values returned to normal. NTG reduced the blood pressure in a higher percentage of hypertensive events. The rates of success were 84% for NTG vs 72% for ISDN in the prebypass phase, 93% vs 64% in the postbypass phase, and 71% vs 54% in the postoperative phase. Increased ISDN effectiveness may be attained with the use of a bolus administration before continuous infusion or with the use of a rapid rate of infusion.