CARPROFEN AS AN ANALGESIC FOR POSTOPERATIVE PAIN IN CATS - DOSE TITRATION AND ASSESSMENT OF EFFICACY IN COMPARISON TO PETHIDINE HYDROCHLORIDE

The aim of this study was to titrate the optimal dose of carprofen for single dose usage, for alleviating postoperative pain, under a double -blind and randomised protocol, using both negative and positive contr ols. Renal tolerance was assessed by screening plasma urea and creatin ine. Pre- and postoperative assessment of pain and sedation was made u sing a dynamic and interactive visual analogue scoring system in 60 ca ts undergoing ovariohysterectomy. The cats were randomly assigned to o ne of six groups: (1) carprofen at 1.0 mg/kg subcutaneously (sc); (2) carprofen at 2.0 mg/kg sc; (3) carprofen at 4.0 mg/kg sc; (4) pethidin e at 5.0 mg/kg intramuscularly (im), (5) pethidine at 10.0 mg/kg im; a nd (6) no analgesics (injection of saline). All injections were given postoperatively on tracheal extubation and administered in a double-bl ind manner. Assessments were made up to 20 hours post extubation. Prio r to induction and at 20 hours post extubation, blood samples were tak en for laboratory analysis of the urea and creatinine content to check for any adverse effect on renal function. Cats given pethidine did no t appear more sedated than the groups receiving carprofen or saline. C ats receiving carprofen were in less pain postoperatively overall, wit h 4.0 mg/kg being the most effective dose rate (significantly better t han the other doses of carprofen at four and eight hours post extubati on). The highest dose of pethidine provided significantly better analg esia than the highest dose of carprofen up to two hours post extubatio n, but from two to 20 hours post extubation carprofen at 4.0 mg/kg pro vided significantly better analgesia than the pethidine. None of the a nalgesic regimens appeared to affect renal function adversely, as meas ured by urea and creatinine levels.