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 ≥ 100 mm Hg, at which time baseline cardiovascular values, pulmonary arterial temperature, end-tidal CO2 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.
Case Description—A 7-year-old Quarter Horse gelding was hospitalized in Ocala, Fla, because of lethargy, fever, anorexia, and swelling of distal aspects of the limbs. A tentative diagnosis of equine piroplasmosis (EP) was made on the basis of examination of a blood smear. The case was reported to the Florida State Veterinarian, and infection with Babesia equi was confirmed. The subsequent investigation included quarantine and testing of potentially exposed horses for B equi and Babesia caballi infections, tick surveillance, and owner-agent interviews.
Clinical Findings—210 horses on 25 premises were tested for infection with EP pathogens. Twenty B equi–infected horses on 7 premises were identified; no horses tested positive for B caballi. Seven horses, including the index case, had clinical findings consistent with EP Dermacentor variabilis was considered the only potential tick vector for B equi collected, and all D variabilis specimens tested negative for Babesia organisms via PCR assay. Results of the epidemiological investigation suggested that B equi was spread by use of shared needles and possibly blood transfusions. All horses that tested positive were involved in nonsanctioned Quarter Horse racing, and management practices were thought to pose substantial risk of transmission of blood-borne pathogens.
Treatment and Outcome—Final outcome of B equi–infected horses was euthanasia, death from undetermined causes, or shipment to a US federal research facility.
Clinical Relevance—This investigation highlights the importance of collaboration between private veterinary practitioners, state veterinary diagnostic laboratories, and regulatory officials in the recognition, containment, and eradication of foreign animal disease.