Cardiovascular effects of desflurane in mechanically ventilated calves.

Objective: To determine cardiovascular effects of desflurane in mechanically ventilated calves.

Animals: 8 healthy male calves.

Procedure: Calves were anesthetized by face mask administration of desflurane to permit instrumentation. Administration of desflurane was temporarily discontinued until mean arterial blood pressure increased to >or= 100 mm Hg, at which time baseline cardiovascular values, pulmonary arterial temperature, end-tidal CO(2) tension, and end-tidal desflurane concentration were recorded. Cardiac index and systemic and pulmonary vascular resistances were calculated. Arterial blood gas variables were measured and calculated. Mean end-tidal concentration of desflurane at this time was 3.4%. After collection of baseline values, administration of 10% end-tidal concentration of desflurane was resumed and calves were connected to a mechanical ventilator. Cardiovascular data were collected at 5, 10, 15, 30, and 45 minutes, whereas arterial blood gas data were collected at 15 and 45 minutes after collection of baseline data.

Results: Mean +/- SD duration from beginning desflurane administration to intubation of the trachea was 151 +/- 32.8 seconds. Relative to baseline, desflurane anesthesia was associated with a maximal decrease in arterial blood pressure of 35% and a decrease in systemic vascular resistance of 34%. Pulmonary arterial blood temperature was decreased from 15 through 45 minutes, compared with baseline values. There were no significant changes in other measured variables. All calves recovered from anesthesia without complications.

Conclusions And Clinical Relevance: Administration of desflurane for induction and maintenance of general anesthesia in calves was smooth, safe, and effective. Cardiopulmonary variables remained in reference ranges throughout the study period.