Interpleural analgesia [published erratum appears in Heart Lung 1991 Jul;20(4):413] Postoperative pain relief is necessary not only for patient comfort, but also to facilitate ventilation and ambulation. The use of opioid analgesia, either intravenously, intramuscularly, or intraspinally, may be ineffective and can cause respiratory depression. The administration of local anesthetics into the pleural space is a technique of providing analgesia of rapid onset and long duration. This analgesia is accomplished without causing the respiratory depression or sedation associated with the use of opioids. Because innovative analgesic methods are often selected for critically ill patients presenting after surgery in the intensive care setting, critical care nurses may encounter patients receiving local anesthetics administered via interpleural catheter. 