Pharmacokinetics, intraoperative effect and postoperative analgesia of tramadol in cats.
Tramadol is a synthetic codeine analogue used as an analgesic in human and veterinary medicine, but not approved for use in cats. Tramadol (2 mg/kg) was administered intravenously (IV) as preoperative analgesic in 12 cats (6 males) undergoing surgical gonadectomy. The pharmacokinetic profile of the drug and its O-desmethyl metabolite were determined in 8 animals (4 males), while intraoperative effects and postoperative analgesia, estimated by subjective pain score (0-24), were evaluated in all. Mean intraoperative isoflurane consumption was reduced, but hypoventilation was not observed. Sex-related differences were not observed, particularly in terms of postoperative analgesia: rescue analgesic was never administered. Concentrations of the active O-desmethyl metabolite were persistently high in all the animals. Considering the results obtained in this study, tramadol, at the dose of 2 mg/kg IV, did not produce any evident intraoperative cardiorespiratory side effects and with additional investigation may prove to be an appropriate intraoperative analgesic in cats undergoing gonadectomy.
Cagnardi
P
P
Department of Veterinary Sciences and Technologies for Food Safety, University of Milan, I 20133 Milan, Italy. petra.cagnardi@unimi.it
Villa
R
R
Zonca
A
A
Gallo
M
M
Beccaglia
M
M
Luvoni
G C
GC
Vettorato
E
E
Carli
S
S
Fonda
D
D
Ravasio
G
G
D000698:Analgesia / Q000662:veterinary*; D000818:Animals; D002415:Cats; D004305:Dose-Response Relationship, Drug; D005260:Female; D007275:Injections, Intravenous / Q000662:veterinary; D007432:Intraoperative Period; D008297:Male; D009294:Narcotics / Q000008:administration & dosage / Q000097:blood / Q000493:pharmacokinetics* / Q000494:pharmacology; D010147:Pain Measurement / Q000662:veterinary; D011184:Postoperative Period; D014147:Tramadol / Q000008:administration & dosage / Q000097:blood / Q000493:pharmacokinetics* / Q000494:pharmacology
D009294:Narcotics; D014147:Tramadol