INFLUENCE OF MEDETOMIDINE ON ACID-BASE-BALANCE AND URINE EXCRETION INGOATS

Seven goats were given medetomidine 5 mu g/kg as an iv bolus injection . Venous blood samples were taken repeatedly and urine was collected c ontinuously via a catheter up to 7h after the injection. Medetomidine caused deep clinical sedation. Base excess, pH and PCO2 in venous bloo d rose after medetomidine administration. There were no significant ch anges in plasma concentrations of sodium, calcium, magnesium, creatini ne or osmolality, whereas potassium and bicarbonate concentrations inc reased, and phosphate and chloride decreased. Medetomidine increased p lasma glucose concentration, and in 4 of 7 goats glucose could also be detected in urine. Medetomidine did not influence urine flow rate, fr ee water clearance, bicarbonate and phosphate excretion or pH, but ren al chloride, sodium, potassium, calcium, magnesium and creatinine excr etion were reduced. The results suggest that the metabolic alkalosis r ecorded after medetomidine administration is not caused by increased r enal acid excretion.