Studies were primarily related to the assessment of pain in relation to surgical procedures , and no clear distinction was made concerning the onset of acute and chronic pain .
The metrics used within the tools appeared to focus primarily on the sensory aspect of pain , with no study clearly discriminating between the sensory and affective components of pain .
Objectives The objectives were to review systematic ally the range of assessment tools used in cats to detect the behavioural expression of pain and the evidence of their quality ; and to examine behavioural metrics ( considering both the sensory and affective domains ) used to assess pain .
Comparison of perioperative racemic methadone, levo-methadone and dextromoramide in cats using indicators of post-operative pain.
OBJECTIVE To compare three opioid agonist drugs for perioperative analgesia in cats . STUDY DESIGN Prospect i ve , blind , controlled , r and omised trial . ANIMALS Ninety client-owned cats , weighing 3.1 ( 2.1 - 4.5 ) kg , aged 14.6 ( 6.0 - 84.0 ) months , were studied . METHODS Seventy-six cats , scheduled for ovariectomy , received either 0.6 mg kg(-1 ) racemic methadone , 0.3 mg kg(-1 ) levo-methadone , 0.05 mg kg(-1 ) dextromoramide or a saline placebo IM . Behaviour and body position were assessed and scored 20 minutes later by a single ' blinded ' observer . Anaesthesia was induced with propofol and maintained with halothane .  Heart rate ( HR ) , respiratory rate ( RR ) , Fe'CO2 and SpO2 were recorded during anaesthesia . Post-operatively , pain was categorised as absent , moderate or severe , on the basis of appearance , behaviour and response to palpation of the surgical wound ( pain score ) . Appearance , pain scores and physiological variables were monitored every 30 minutes , for a duration of 4 hours . Differences between time-dependent continuous variables were analysed using mixed models for repeated measurements . Differences in categorical , time-dependent variables were analysed using chi2-tests . Significance was set at p < or = 0.05 . RESULTS There were no significant changes in appearance after pre-anaesthetic medication . After surgery , there was no association between appearance and pain score with HR or RR . The assessment of pain depended on comparison with the placebo group , by comparing animals ' reactions to wound palpation . Sixteen of the 18 cats in the placebo group and 14 of the 19 cats in the dextromoramide group showed signs of moderate-to-severe pain after surgery . In the levo-methadone group ( n = 20 ) , one animal showed pain after 60 minutes and two after 120 minutes . One cat in the racemic methadone group ( n = 19 ) showed pain signs and behavioural changes at 60 minutes . Compared to the two methadone groups , ' rescue ' analgesia was required more often in cats treated with dextromoramide or saline . CONCLUSION AND CLINICAL RELEVANCE Dextromoramide ( 0.05 mg kg(-1 ) ) was ineffective , while racemic methadone ( 0.6 mg kg(-1 ) ) and levo-methadone ( 0.3 mg kg(-1 ) ) provided effective analgesia in cats following ovariectomy , without behavioural , respiratory or cardiovascular side effects
Studies were primarily related to the assessment of pain in relation to surgical procedures , and no clear distinction was made concerning the onset of acute and chronic pain .
The metrics used within the tools appeared to focus primarily on the sensory aspect of pain , with no study clearly discriminating between the sensory and affective components of pain .
Objectives The objectives were to review systematic ally the range of assessment tools used in cats to detect the behavioural expression of pain and the evidence of their quality ; and to examine behavioural metrics ( considering both the sensory and affective domains ) used to assess pain .