Arterial blood gas parameters in pet rabbits anaesthetized using a combination of fentanyl-fluanisone-midazolam-isoflurane

OBJECTIVES: Blood gas analysis is a well-recognized method to monitor pulmonary function, blood oxygenation, ventilation and acid-base status during general anaesthesia. The aim of this study was to report blood gas analysis results in pet rabbits (Oryctolagus cuniculus) obtained during general anaesthesia using a portable clinical analyser. METHODS: Thirty-two rabbits were premedicated with 0·2 mL/kg fentanyl and fluanisone. Anaesthesia was induced with 0·2 mg/kg midazolam and maintained with 2% isoflurane in oxygen via endotracheal tube. Arterial blood samples were taken from the central ear artery 10 minutes after induction of anaesthesia. RESULTS: Respiratory acidaemia was observed during anaesthesia. Mean ±sd (range) arterial blood pH was 7·33 ±0·08 (7·15 to 7·48). PaCO2 and PaO2 were, respectively, 55·02 ±10·5 (37·7 to 92·1) mmHg and 370·0 ±120·5 (67 to 561) mmHg. Base excess was 2·8 ±3·6 (-3 to 11) mmol/L, HCO3 was 28·73 ±3·07 (23·7 to 35·4) mmol/L and TCO2 was 30·4 ±3·2 (25 to 37) mmol/L. None of the rabbits developed haematoma during arterial blood collection or ischaemia of the pinna during the hospitalization period. CLINICAL SIGNIFICANCE: Arterial blood gas analysis is a safe and easy to perform diagnostic technique that can contribute to improved safety of rabbit anaesthesia, by providing information on the respiratory and metabolic status of the patient.