Antinociceptive and motor-blocking action of epidurally administered IQB-9302 and bupivacaine in the dog.
OBJECTIVE
The aim of this study was to compare the antinociceptive and motor-blocking effects of epidurally administered IQB-9302 (C18H26N2O.HCl) and bupivacaine in the dog.


METHODS
Twelve adult female Beagle dogs were used. Each animal received 3 concentrations (0.25%, 0.50%, and 0.75%) of either IQB-9302 (n = 6) or bupivacaine (n = 6) by means of a chronic epidural catheter. The nocifensive and motor-blocking status were determined at regular intervals before (baseline) and after drug administration.


RESULTS
Epidurally administered IQB-9302 caused a more potent nocifensive and motor-blocking action than bupivacaine. The duration of complete nocifensive block was the longest with IQB-9302, whereas the duration of dermatome nocifensive block was similar for both drugs. The nocifensive to motor block ratio was significantly higher with IQB-9302.


CONCLUSIONS
IQB-9302 produced an anesthetic action similar to that of bupivacaine, although the former drug induced a slightly more potent nocifensive block. Nocifensive and motor block duration are very similar with IQB-9302, whereas bupivacaine induces a more prolonged motor block without nocifensive block.
Gómez de Segura
I A
IA
Department of Experimental Surgery, La Paz University Hospital, Madrid, Spain. ialvarez@hulp.es
Vazquez
I
I
De Miguel
E
E
D018712:Analgesics, Non-Narcotic / Q000494:pharmacology*; D000767:Anesthesia, Epidural; D000779:Anesthetics, Local / Q000494:pharmacology*; D000818:Animals; D002045:Bupivacaine / Q000494:pharmacology*; D004285:Dogs; D004305:Dose-Response Relationship, Drug; D005260:Female; D010880:Piperidines / Q000494:pharmacology*; D013997:Time Factors
D018712:Analgesics, Non-Narcotic; D000779:Anesthetics, Local; C418003:IQB 9302; D010880:Piperidines; D002045:Bupivacaine