Pain management

Pain is a disagreeable subjective physiological and psychosocial experience that often serves a biological purpose (warning of injury). It incorporates both the perception of a painful stimulus and the response to the aforementioned perception. It has been posited that the severity of pain does not necessarily correlate with the degree of tissue damage, and that a patient's individual expression and experience of pain is both complex and unique. Being highly subjective, pain is therefore difficult to quantify. The most widely used scales for evaluating the experience of pain in patients are the visual analogue scale (VAS) and the numeric rating scale (NRS), with behavioural rating scales also showing efficacy in estimating whether patients with cognitive impairment are in pain.