Changes in thermal threshold response in eight cats after administration of buprenorphine, butorphanol and morphine

Abstract

Thermal thresholds were measured in eight cats after the intramuscular administration of morphine (0.2 mg/kg), buprenorphine (0.01 mg/kg) or butorphanol (0.2 mg/kg), doses commonly used in clinical practice; 0.9 per cent saline (0.3 ml) was injected as a control. Groups of six cats were used and each cat participated in at least two treatments, according to a randomised design. The investigator was blinded to the treatments. The thermal thresholds were measured with a testing device developed specifically for cats, and measurements were made before and five, 30, 45 and 60 minutes and two, four, six, 12 and 24 hours after the injections. There was no significant change in thermal threshold after the injection of saline. With butorphanol, the threshold was increased only at five minutes after the injection and was decreased two hours after the injection; with morphine it was increased from between four and six hours after the injection, and with buprenorphine it was increased from between four and 12 hours after the injection.

Pharmacokinetic and pharmacodynamic modelling after subcutaneous, intravenous and buccal administration of a high-concentration formulation of buprenorphine in conscious cats

“…The test has been validated in free-ranging cats [7] and several studies using the TT device and evaluating the antinociceptive effects of buprenorphine have been reported in the species [3, 8–16]. The equipment was calibrated and maintained according to the manufacturer’s recommendations.…”

Body weight affects behavioural indication of thermal nociceptive threshold in adult domestic cats (Felis catus)

“…It may be particularly difficult to assess such variations in small cohort studies but the effects of inter-individual variability could, to some extent, be reduced if comparisons between treatments are made using the same test subjects (e.g. Robertson et al, 2003). Otherwise this work suggests that future studies involving thermal nociception should attempt to standardise the body weight of cats used or include weight as a covariate in any analyses.…”

Pain management in cat

“…Η αναλγητική δράση της ασκείται μέσω της διέγερσης των κ-υποδοχέων και είναι απο τελεσματικότερη έναντι του σπλαχνικού πόνου, ενώ παράλληλα έχει και ήπια ηρεμιστική δράση (Sawyer et al 1991, Wagner 1999. Σε πειραματικές συνθήκες, οι Robertson et al (2003b), ελέγχοντας την αντίδραση του ζώου σε θερμικό ερέθισμα, διαπίστωσαν πολΰ μι κρή διάρκεια δράσης και περιορισμένο αναλγητικό αποτέλεσμα, το οποίο ήταν ανεξάρτητο από τη χορη γούμενη δόση. Όμως, δεν είναι σαφές αν ένα τέτοιο ερέθισμα προσομοιάζει στο σωματικό πόνο και με δε δομένο ότι μια αναλγητική ουσία μπορεί να έχει καλό αποτέλεσμα έναντι ενός μόνο είδους ερεθίσματος, δεν είναι δυνατόν να αξιολογηθεί με βεβαιότητα η δράση της βουτορφανόλης έναντι του σωματικού πόνου στη γάτα, με βάση τα αποτελέσματα της έρευνας που προ αναφέρθηκε.…”