BIOCHEMICAL AND HEMATOLOGICAL-CHANGES FOLLOWING PROLONGED HALOTHANE ANESTHESIA IN HORSES

Six healthy horses were anaesthetised with halothane (1.2 times the ho rse minimal alveolar concentration) in oxygen for more than 12 hours. Serum bilirubin, aspartate aminotransferase, alkaline phosphatase and L-iditol dehydrogenase values were significantly (P<0.05) increased fo r up to nine days after anaesthesia. These changes suggest an anaesthe sia related liver dysfunction. Creatine kinase increased to an average of more than 1400 iu litre-1 24 hours after anaesthesia and this chan ge is indicative of muscle cell disruption. Renal-associated biochemic al results, (that is serum creatinine and inorganic phosphate concentr ations) were significantly increased transiently and are indicative of reduced renal function during and immediately after anaesthesia. Plas ma concentrations of eicosanoids (6-keto-PGF1a, PGF2a, PGE and thrombo xane) following anaesthesia were not different from preanaesthetic val ues. The magnitude of liver and muscle cell related increases in serum enzyme activities resulting from prolonged halothane anaesthesia was in excess of that previously reported for anaesthesia of shorter durat ion.