Research Tools for the Measurement of Pain and Nociception

SIMPLE SUMMARY: Pain is an integral aspect of many diseases and it is important to be able to measure it in the clinic so that the progression of disease and the animal’s response to treatment can be monitored. When research into pain is undertaken, it is also important to be able to measure the pain, but this time the aim is to provide meaningful results that will further our understanding of the mechanisms of pain or how it can be better treated. This change in emphasis between clinical and research measurement of pain means that the advantages and disadvantages of the many ways in which pain can be measured influence the choice of the most suitable technique and the way in which it is used. It is important to carefully select the most appropriate methodologies so that the data generated are relevant to the hypotheses being tested. ABSTRACT: There are many ways in which pain in animals can be measured and these are based on a variety of phenomena that are related to either the perception of pain or alterations in physical or behavioural features of the animal that are caused by that pain. The features of pain that are most useful for assessment in clinical environments are not always the best to use in a research environment. This is because the aims and objectives of the two settings are different and so whilst particular techniques will have the same advantages and disadvantages in clinical and research environments, these considerations may become more or less of a drawback when moving from one environment to the other. For example, a simple descriptive pain scale has a number of advantages and disadvantages. In a clinical setting the advantages are very useful and the disadvantages are less relevant, but in a research environment the advantages are less important and the disadvantages can become more problematic. This paper will focus on pain in the research environment and after a brief revision of the pathophysiological systems involved will attempt to outline the major advantages and disadvantages of the more commonly used measurement techniques that have been used for studies in the area of pain perception and analgesia. This paper is expanded from a conference proceedings paper presented at the International Veterinary Emergency and Critical Care Conference in San Diego, USA.