Are all effects of esmolol equally rapid in onset

摘要: The purpose of this study was to compare the time course bradycardic and hypotensive effects esmolol. Ten patients undergoing craniotomy requiring hypotension were anesthetized with nitrous oxide isoflurane. During steady state anesthesia, response an infusion esmolol 500 μg.kg -1 .min for 90 s followed by 300 measured over 60 min. Heart rate (HR), mean arterial pressure (MAP), plasma renin activity (PRA) responses did not occur equal rapidity. half-time 14% decrease in HR (81 ± 13 bpm 70 9 bpm) 1.2 MAP decreased 26% (85 7 mm Hg 63 6 Hg) a 17.8 min half-time. This delay may, part, be related gradual 44% decline PRA (9.5 4.5 ng.mL .h 5.3 2.5 ng mL . h ) occurring 11.9 times attainment 90% maximum decreases 4.8 3.0 HR, 42.5 8.9 MAP, 32.1±15.0 PRA. Thus although has ultrashort kinetic half-life, only effect can considered have onset. (Anesth Analg 1995 ;81 :297-300)