[Clinical evaluation of isosorbide dinitrate (ISDN) spray: a study on the plasma concentrations of ISDN and on its hemodynamic effects using three administration routes].

The effects of ISDN spray has been evaluated using oral, nasal or tracheal routes in patients under enflurane anesthesia. These 30 patients were in ASA I or II physical status without cardiovascular, kidney or liver diseases. Under enflurane anesthesia, hemodynamic parameters (blood pressure and heart rate), blood gas and plasma concentration of ISDN were measured at several points before and after drug administration. The plasma concentration reached a maximum point (C max) 4 min after drug administration in the oral group (O-group) and nasal group (N-group), and the values obtained were 48.4 +/- 5.4 ng.ml-1 and 87.4 +/- 13.8 ng.ml-1 respectively. The C max of the N-group was significantly higher than that of O-group (P less than 0.05). In the O- and N-groups, systolic blood pressure decreased 10% and 17%, after 4 min (P less than 0.05) and recovered 20 after min. Diastolic blood pressure decreased in both groups after 4 min (P less than 0.05). Heart rate significantly increased in the N-group (P less than 0.05), and continued to change up to 60 min after drug administration. In both groups, PaO2/FIO2 decreased 14% and 9% after 10 min (P less than 0.01). In the tracheal group, plasma concentration did not increase and these hemodynamic changes were not observed. These results suggest that nasal route of ISDN spray is the best route of administration.