Comparison of sevoflurane and isoflurane in dogs anaesthetised for clinical surgical or diagnostic procedures.
OBJECTIVE
To assess attributes of sevoflurane for routine clinical anaesthesia in dogs by comparison with the established volatile anaesthetic isoflurane.


METHODS
One hundred and eight dogs requiring anaesthesia for elective surgery or diagnostic procedures were studied. The majority was premedicated with 0.03 mg/kg of acepromazine and 0.01 mg/kg of buprenorphine or 0.3 mg/kg of methadone before induction of anaesthesia with 2 to 4 mg/kg of propofol and 0.5 mg/kg of diazepam. They were randomly assigned to receive either sevoflurane (group S, n=50) or isoflurane (group I, n=58) in oxygen and nitrous oxide for maintenance of anaesthesia. Heart rate, respiratory rate, indirect arterial blood pressure, haemoglobin saturation, vaporiser settings, end-tidal carbon dioxide and anaesthetic concentration and oesophageal temperature were measured. Recovery was timed. Data were analysed using analysis of variance and non-parametric tests.


RESULTS
Heart rate (85 to 140/minute), respiratory rate (six to 27/minute) and systolic arterial blood pressure (80 to 150 mmHg) were similar in the two groups. End-tidal carbon dioxide between 30 and 60 minutes (group S 6.4 to 6.6 and group I 5.8 to 5.9 per cent) and vaporiser settings throughout (group S 2.1 to 2.9 and group I 1.5 to 1.5 per cent) were higher in group S. There was no difference in time to head lift (18+/-16 minutes), sternal recumbency (28+/-22 minutes) or standing (48+/-32 minutes). No adverse events occurred.


CONCLUSIONS
Sevoflurane appeared to be a suitable volatile anaesthetic for maintenance of routine clinical anaesthesia in dogs.
Bennett
R C
RC
Department of Clinical Veterinary Medicine, University of Cambridge, Cambridge CB3 OES, UK.
Fancy
S P J
SP
Walsh
C M
CM
Brown
A J
AJ
Taylor
P M
PM
D000762:Anesthesia Recovery Period; D018685:Anesthetics, Inhalation; D000818:Animals; D001794:Blood Pressure / Q000187:drug effects; D002245:Carbon Dioxide / Q000097:blood; D004285:Dogs / Q000502:physiology*; D004739:England; D006339:Heart Rate / Q000187:drug effects; D007530:Isoflurane; D008738:Methyl Ethers; D008991:Monitoring, Physiologic / Q000662:veterinary; D011229:Preanesthetic Medication / Q000662:veterinary; D012119:Respiration / Q000187:drug effects; D000077149:Sevoflurane; D016896:Treatment Outcome
D018685:Anesthetics, Inhalation; D008738:Methyl Ethers; D002245:Carbon Dioxide; D000077149:Sevoflurane; D007530:Isoflurane