Pain

Pain is a complex biopsychosocial phenomenon that most human beings experience at different times throughout their life span. This phenomenon has perplexed man for centuries, and for centuries pain has been poorly managed. Today, health care professionals are placed in a position where patients rely on them to provide pain control, and effective pain management is important in enabling patients to progress in their rehabilitation and to have an improved quality of life. This entry reviews definitions of pain, summarizes the demographics and epidemiology of pain, and describes the physiology of pain and its categorization. It also considers the interventions available, as well as some of the ethical issues that arise with respect to pain treatment.

Ancient civilizations, including early Mesopotamia, Egypt, China, Greece, and Rome, used various primitive approaches to treat pain. Via writings, carvings, and other documents, anthropologists have found evidence of pain interventions, including ancient pharmacopoeia such as the use of opium, scopolamine, ephedrine, ginseng, Siberian wort, snake venom, and various other treatments. Nonpharmacological interventions included prayer, dance rituals, music, bloodletting, hydrotherapy, and other cultural remedies.

The universally accepted definition of pain, according to the International Association for the Study of Pain (IASP) and the American Pain Society (APS), is ‘an unpleasant sensory and emotional experience associated with actual or potential tissue damage or described in terms of such damage’ (Mersky, 1986, p. S217). This definition does not ask for organic proof that pain exists. A second definition coined by McCaffery (1968) says, ‘pain is whatever the experiencing person says it is, whenever the experiencing person says it is (p. 95).’ This definition points to the subjectivity of pain. Pain is experienced differently by individuals based on their cultural background, upbringing, personal values, genetics, and the meaning they attribute to pain.

Pain is a protective mechanism that provides warning of assaults or damage to or within the body; however, if left untreated, this protective mechanism can become a chronic and destructive condition. Unrelieved pain remains a critical problem in all areas of health care. The most undertreated populations include children, the elderly, minorities, and women mostly due to myths and misconceptions related to the pain mechanism. Toward the end of the 20th century and the beginning of the current century, the undertreatment of pain became increasingly evident as interested health care professionals studied this problem. Several organizations, most notably the Joint Commission on Accreditation of Health Care Organizations (JCAHO), have developed standards, publications, and guidelines for practice related to the relief of pain and care at the end of life.