Patient controlled analgesia: drug options, infusion schedules, and other considerations.

Patient controlled analgesia (PCA) has a number of advantages compared with traditional methods of pain management. Some of these advantages include superior pain relief, less sedation due to superior drug titration, increased psychological satisfaction due to patient control of pain management, individualized analgesic dosing, decreased staff time for patient care, and increased patient activity and mobility. Although a few cases of respiratory depression have been reported with the use of PCA, there is a relatively low risk of this complication in most patient populations. Appropriate candidates for PCA include terminally ill-cancer patients, postoperative patients, mentally clear and alert trauma patients, and patients who require massive doses of oral narcotics to control pain but are experiencing intolerable side effects. This article focuses on the principles involved in selecting the optimal analgesic and the therapeutic variables involved in using PCA.