Effects of the anaesthetic/tranquillizer treatments on selected plasma biochemical parameters in NZW rabbits

In order to assess the response of plasma biochemical parameters to anaesthesia, 40 New Zealand White (NZW) rabbits were assigned to four treatment groups (n = 10): control (1 ml i.v. saline solution), fentanyl-droperidol (FD) (0.4 ml/kg s.c. of 'thalamonal' solution; 2.5 mg/ml droperidol, 0.05 mg/ml fentanyl), ketamine (K) (10 mg/kg i.v.) with either xylazine (X) (3 mg/kg i.v.) or diazepam (D) (2 mg/kg i.v.). Blood samples were obtained from the central ear artery at six time points: before injection, and at 10, 30, 60, 120 min and 24 h after injection of the anaesthetics/saline. Plasma ALT, AST, ALP, GGT, BUN, creatinine, phosphate and potassium levels were measured by the Hitachi 747 autoanalyser. The administration of K-X increased (P < 0.05) plasma ALT (from 11.4 +/- 0.9 to 20.2 +/- 1.7 IU/l, at 10 min), AST (from 10.5 +/- 3.3 to 34 +/- 2.1 IU/l, at 120 min), BUN (from 17.2 +/- 0.9 to 25.8 +/- 1.8 mg/dl, at 60 min) and creatinine concentrations (from 1 +/- 0.1 to 1.6 +/- 0.2 mg/dl, at 10 min). After K-D administration, we observed an increase (P < 0.05) in plasma ALT (from 11.4 +/- 0.9 to 20.2 +/- 1.1 IU/l, at 10 min), AST (from 11.4 +/- 1.6 to 28 +/- 3.7 IU/l, at 10 min), BUN (from 15.8 +/- 0.8 to 30 +/- 1.5 mg/dl, at 10 min) and creatinine levels (from 1 +/- 0.08 to 2.2 +/- 0.2 mg/dl, at 120 min). No significant changes were seen in the FD group. We conclude that K-X and K-D may affect plasma concentration of select serum enzymes and biochemical parameters. These results should be taken into account when blood samples are evaluated in treated rabbits.