Pathophysiology of Pain

While acute pain is an alarm signal involving unpleasant sensations and vegetative and behavioural reactions, chronic pain presents with long-lasting consequences. The underlying mechanisms of pain chronicization after an acute pain episode involve both peripheral and central nervous system sensitization. In this chapter, the pathophysiology of acute and chronic pain will be described with a specific focus on elderly patients. Ageing is accompanied by physiological changes, and acute and chronic pain are a major concern for older people. Knowledge of the clinical manifestations of pain processing changes in older people is essential in guaranteeing optimal pain management.