CARDIOPULMONARY EFFECTS OF DESFLURANE IN THE DOG DURING SPONTANEOUS AND ARTIFICIAL-VENTILATION

The cardiopulomary effects of desflurane al end tidal concentrations o f 10.3, 12.9 and 15.5 per cent during either spontaneous or artificial ventilation were studied in five beagle dogs. Desflurane anaesthesia resulted in tachycardia and a decrease in arterial blood pressure whic h were not significantly related to the end tidal desflurane concentra tions or the mode of ventilation. At an end tidal desflurane concentra tion of 15.5 per cent there was a significant increase in central veno us and pulmonary arterial wedge pressures and, with artificial ventila tion, a reduction in cardiac output and stroke volume when compared wi th similar measurements at an end tidal desflurane concentration of 10 .3 per cent. When allowed to breathe spontaneously, the dogs panted at times when they were lightly anaesthetised, but their respiration was depressed to a varying extent at the highest end tidal desflurane con centration. The induction of anaesthesia with desflurane was smooth, a nd the quality of anaesthesia during maintenance was excellent. There was one episode of a transient tachyarrhythmia associated with the mea surement of cardiac output, but no other side effects were observed.