The idea of administering repeated small doses of a drug intravenously is not new, but it took many years for the method to become part of the routine clinical management of pain. The traditional practice of administering an opioid in a predetermined dose by intramuscular or subcutaneous injection, and at predetermined minimal intervals, led to usually inadequate and intermittent pain relief. The dosage of opioid was often determined so as to be conservative and 'safe', and administration depended on patient request and availability of nursing staff. In 1963, Roe described the widely differing analgesic requirements among postoperative patients. He managed postoperative pain by titrating small intermittent intravenous boluses of morphine at intervals of 10 to 30 minutes, until it was observed that adequate relief had been obtained. He found that pain relief was more effective than with intramuscular analgesics and required smaller total doses.
展开▼
