Effects of nicardipine, nitroglycerin, and nitroprusside on left ventricular diastolic function during enflurane anesthesia.
The purpose of this study was to evaluate the effects of nicardipine (NCR), nitroglycerin (NTG), or nitroprusside (SNP) on left ventricular diastolic function during enflurane anesthesia in acutely instrumented dogs. Using echocardiography, time constants for the decline in isovolumic left ventricular pressure (T), stiffness constant (K), diastolic time intervals, and left ventricular filling rates were measured in 21 mongrel dogs during the following conditions: (1) 0% enflurane (control), (2) 3.3% enflurane, (3) intravenous infusion of NCR, 1 microgram/kg/min, NTG, 2 micrograms/kg/min, or SNP, 2 micrograms/kg/min, during 3.3% enflurane, and (4) intravenous infusion of NCR, 2 micrograms/kg/min, NTG, 4 micrograms/kg/min, or SNP, 4 micrograms/kg/min, during 3.3% enflurane. During 3.3% enflurane anesthesia, T and K increased significantly, and left ventricular filling rates decreased. The administration of NCR, NTG, or SNP returned T and K to control levels. Left ventricular rapid filling rate returned toward the control level only with NCR (P < 0.05, NCR v NTG, SNP). It is concluded that the depression of diastolic function during enflurane anesthesia was improved by NCR or other vasodilators. The extent and mechanism of action of these vasodilators might differ, however.
Koyama
K
K
Department of Anesthesiology, School of Medicine, Keio University, Tokyo, Japan.
Yamada
T
T
Takeda
J
J
Sato
M
M
Toyoda
Y
Y
Fukushima
K
K
Kawazoe
T
T
D000769:Anesthesia, Inhalation; D000818:Animals; D016279:Atrial Function, Left / Q000187:drug effects; D002302:Cardiac Output / Q000187:drug effects; D002306:Cardiac Volume / Q000187:drug effects; D003971:Diastole / Q000187:drug effects*; D004285:Dogs; D004452:Echocardiography; D004548:Elasticity; D004737:Enflurane; D009200:Myocardial Contraction / Q000187:drug effects; D009529:Nicardipine / Q000494:pharmacology*; D005996:Nitroglycerin / Q000494:pharmacology*; D009599:Nitroprusside / Q000494:pharmacology*; D010701:Phonocardiography; D011669:Pulmonary Wedge Pressure / Q000187:drug effects; D016277:Ventricular Function, Left / Q000187:drug effects*; D017725:Ventricular Pressure / Q000187:drug effects
D009599:Nitroprusside; D004737:Enflurane; D009529:Nicardipine; D005996:Nitroglycerin