Validation of World Health Organization guidelines for cancer pain relief during the last days and hours of life.

The efficacy of the World Health Organization's guidelines for cancer pain relief was examined in 401 dying patients. At the time of death, only 3% of the patients experienced severe or very severe pain; whereas 52% had no pain at all, 24% experienced only mild or moderate pain, and 20% were unable to rate their pain intensity. Analgesic drugs were the mainstay of therapy during the last 24 hr of life, being administered by mouth in 47% and parenterally in 44% of the patients. Only 9% of the patients required no systemic analgesics. Nonopioid analgesics alone were effective in 5% and a combination of nonopioids and "weak" opioids were effective in 16% of the patients. In the remaining 70% of the patients "strong" opioids alone or in combination with nonopioid analgesics were necessary to achieve adequate pain reduction. Additional adjuvant drugs to treat special types of pain or other symptoms were prescribed in 90% of the patients. Nonpharmacological measures, such as radiotherapy, nerve blocks or neurosurgery played only a very minor role at this stage of the disease. This study shows that cancer pain can be treated satisfactorily until death.