Epidural analgesia in veterinary critical care.

Epidural analgesia has minimal systemic effects and is a useful technique for relieving pain in critical care patients. Before administration, patients must be thoroughly assessed to identify any preexisting conditions that preclude the safe use of this technique. Analgesia can be achieved by administration of local anesthetics, opioids, alpha 2 agonists, or a combination of these analgesic agents. Concurrent administration of more than one drug allows the synergistic interaction of these agents and generally improves the level of analgesia achieved, lengthens the duration of action, and lowers the dose of each drug required to achieve analgesia. Complications of epidural techniques are infrequent and include both iatrogenic and idiopathic problems, most of which have no permanent sequelae. This review provides a detailed description of the epidural analgesia technique and lists multiple sources of specialized supplies necessary for either single injection or epidural catheter placement. It also provides direction for monitoring the critical care patient with an epidural catheter.