The purpose of the investigation was to assess the effects of desflurane (DES) on left ventricular heart function during basal barbiturate anesthesia in a closed-pericardium, closed-chest acute swine model. The study was performed in 11 normoventilated adult pigs. Hemodynamic measurements were obtained using arterial, central venous, and pulmonary artery catheters, as well as a conductance volumetry and tip manometry catheter placed in the left ventricle. Hemodynamic measurements were recorded during basal pentobarbital anesthesia and with the addition of 1%, 2%, 4%, and 6% DES. DES dose-dependently decreased mean arterial pressure, systemic vascular resistance, left ventricular end-systolic pressure, dP/dtMAX and dP/dtMIN. At doses >1%, decreases in CO, stroke volume, ejection fraction, end-systolic elastance, preload recruitable stroke work, preload adjusted maximal power, and peak filling rate were observed. Heart rate decreased at 4% and 6% DES. Isovolumetric relaxation time increased only at 6% DES. We conclude that smaller doses of DES have a significant cardiodepressive effect in the setting of barbiturate infusion, as measured by conductance volumetry.
Implications: Desflurane, in very small doses, depressed cardiac function during pentobarbital anesthesia with ketamine and benzodiazepine premedication in swine, as assessed by conductance volumetry and left ventricular pressure and volume relationship analysis. These results suggest that desflurane, in combination with certain anesthetics, can be cardiodepressive even in very small doses.