Pain control in terminal disease

Pain control is recognised as perhaps the most important single objective in the patient with terminal disease. Cancer, cardiovascular disease and obstructive airways disease are foremost among many causes of pain requiring control in the terminal phase. Spiritual, emotional, religious and socio-economic factors are important in raising or lowering the pain threshold. Analgesic strategies include use of drugs, neurosurgery, radiotherapy and supportive measures which may be brought to bear singly or in combination as required. Pain is clinically classified as being acute or chronic, by the type of patient, and by a series of common pain syndromes and their pathological mechanisms. General concepts of control of pain and discomfort in disease are discussed, together with a brief comment on epidemiology, in the first part of the article. Rationale is then discussed under the following headings: (i) principles of pain control; (ii) causes of pain; and (iii) analgesic modalities and factors impinging on their efficacy.