Right ventricular performance during hypotension induced by prostaglandin E1, nicardipine HCl, glycerine trinitrate, and isosorbide dinitrate.

This study investigated right ventricular (RV) performance during hypotensive anesthesia and compared the effect of the vasodilators prostaglandin E1 (PGE1), nicardipine HCl (Nic), glycerin trinitrate (GTN), and isosorbide dinitrate (ISDN) on RV function. Fifty patients were allocated into four groups [PGE1 (n=20), Nic (n=10), GTN (n=10), and ISDN (n=10)] in random order. Pulmonary and RV hemodynamics were measured using a rapid-response thermodilution catheter before and during induced hypotension, when systolic arterial pressure was maintained at 80 mmHg. In the PGE1, GTN, and ISDN groups, RV end-diastolic volume (RVEDV) and pulmonary vascular resistance were reduced in a similar manner. However, RV ejection fraction increased only in the PGE1 group, and as a consequence, RV stroke volume (RVSV) was maintained. Nic did not change the RV parameters observed, but reduced only systemic vascular resistance (SVR). PGE1 enhanced RV function during induced hypotension. Nic was a useful alternative agent for hypotensive anesthesia. GTN and ISDN reduced RV preload and RVSV; however, cardiac output was maintained by increasing heart rate (HR). Therefore, such nitrates should be used under an adequate RV preload.