[The effect of anesthesia on kidney scintigraphy in the dog]

Renal scintigraphy is one of the diagnostic devices in the upper urinary tract. In 24 dogs of different age, sex and breed that--according to the usual laboratory tests--were considered healthy with respect to renal function, a renal scintigraphy with the tubular excreted tracer 99mTc-MAG3 was performed. The dogs were grouped according to three different anaesthetic regimens in order to estimate the influence of anaesthesia--which is necessary for this investigation--onto function of the normal kidney. Eight dogs were scintigraphed twice using different anaesthesia protocols. In group A (n = 22), anaesthesia was performed with a combination of atropine/diazepam/ketamine/xylazine. The reference range determined was for the period of maximal activity accumulation (Tmax) 3.2 +/- 0.8 min and for the elimination half-time (Tmax/2) 6.3 +/- 1.4 min. MAG3-clearance was 7.5 +/- 1.8 ml/min/kg. Group B (n = 5) received thiopental as a continuous intravenous infusion. Tmax was measured with 2.9 +/- 1.1 min, Tmax/2 with 4.7 +/- 1.2 min and the MAG3-clearance was 6.8 +/- 1.6 ml/min/kg. In group C (n = 5), the dogs were given propofol and halothane, and the values determined for Tmax and Tmax/2 were 4.8 +/- 2.7 and 4.8 +/- 1.4 min, respectively. The MAG3-clearance was 10.0 +/- 2.3 ml/min/kg. It is concluded that the anaesthetic regime used has a distinct influence on the reference values.