Pain

The Multidimensional Nature of Pain

The International Association for the Study of Pain defines pain as “an unpleasant sensory and emotional experience associated with actual or potential tissue damage, or described in terms of such damage.” Pain is inherently subjective. Pain is experienced as a result of a highly complex interaction of physical, biochemical, physiological, cognitive, emotional, behavioral, and sociocultural factors. The brain integrates information from multiple sources to form the experience that is pain. That multiplicity of sources, both aggravating and ameliorating the final experience, makes clinical decision making in relation to pain challenging. The recognition of this complexity has led to the development of multidisciplinary pain teams and the broadening of pain management to include a range of nonpharmacological interventions.

The major aspects of pain are physical, psychological, and environmental. Thus, the experience of pain is a combination of local biochemical changes, sensory information from somatic and visual receptors, visual and other sensory information, intrinsic neural inhibitory inputs, phasic cognitive and emotional inputs (e.g., anxiety) and tonic cognitive and emotional inputs (memory and cultural experiences), and inputs from the body's stress regulation system.

The sociocultural dimension of pain includes demographic characteristics; ethnic background; and cultural, religious, and social factors that influence an individual patient's perceptions of and response to pain. The search for meaning in pain is universal.

The adequacy of the treatment of pain varies enormously around the world. The reasons for inadequacy of treatment include lack of or suboptimal training of clinicians in pain assessment and management, inadequate attention to pain as a symptom, the presence of very restrictive domestic opioid laws, infrastructure weaknesses preventing patients' access to analgesia, opiophobia [Page 852]of clinicians, and medical neglect. In response to this universal challenge, there has been a growing recognition that pain management is a basic human right that places clear obligations, through the international right to healthcare, on national governments. Other legal sources of this right emerge from statutory law, elder abuse law, and the law of medical negligence.

Heuristics and Pain

The spectrum of decision making in pain medicine lies along a continuum from simple to complex and is largely related to the level of uncertainty. That uncertainty may arise in all aspects of management, from the presenting history through to its treatment. In response to that uncertainty, clinicians employ a variety of conscious and unconscious tools from careful reasoning to intuition. One response to the irreducible element of uncertainty in clinical decision making is the use of heuristics. Heuristics are simple rules of thumb or judgments borne out of years of individual and collective experience. Generally, such heuristics are effective, but occasionally, they fail. Good decision making in pain management may be impeded by various cognitive biases or cognitive dispositions to respond.

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