Evaluation of clinical and experimental pain in animals

Abstract

Pain has been historically neglected in animals, however in the last decade, the treatment of pain has advanced considerably, especially with regard to small animals. However, the difficulty of recognizing the nociceptive process, the lack of familiarity with therapeutic strategies and the lack of validated methods that could be used to assess acute and chronic pain or determine the clinical efficacy of drugs, are the main factors contributing to under utilization of analgesics by professionals. This study aims to develop and validate scales for assessment of acute postoperative pain in cattle, horses and pigs, and chronic pain in dogs, applicable to clinical situations. It is also proposed to validate methods of assessing mechanical, thermal and electrical nociceptive thresholds in horses and donkeys after administration of an opioid analgesic. A detailed statistical analysis will be used to perfom qualitative validation of the instruments to measure pain and validate the proposed variables. Verification of relevant variables will be evaluated by Goodman test and the degree of association between variables by testing item-total correlation. The Cronbach's alpha will examine the consistency of the variables together. The validity of the construct will be assessed by the Kappa coefficient of reliability and criterion validity of the correlation coefficient. The agreement between observers for each variable will be analyzed by Friedman test, coefficient of intra-class correlation and multivariate analysis of variance. In addition, in order to establish new strategies for treatment of pain, it will be investigated a slow release system produced by a bioadhesive carrier for administration of oral methadone in horses, correlating with the pharmacokinetic profile. (AU)