Combined lipid emulsion and ACLS resuscitation following bupivacaine- and hypoxia-induced cardiovascular collapse in unanesthetized swine.

This study examined whether combining lipid emulsion and advanced cardiac life support (ACLS) improves survival in an unanesthetized swine model of bupivacaine- and hypoxia-induced cardiovascular collapse. Arterial and venous catheters and a tracheostomy were surgically placed in 26 swine receiving inhalation anesthesia. After a 1-hour recovery period, bupivacaine (5 mg/kg) was administered intravenously over 15 seconds. Following 1 minute of observation and 3 minutes of mechanical airway obstruction, during which all animals exhibited complete cardiovascular collapse, ACLS was initiated. Animals were randomized to receive either intravenous saline or 20% lipid emulsion commencing with the initiation ofACLS. Survival was defined as a return of spontaneous circulation (ROSC) with unsupported blood pressure greater than 60 mm Hg for 10 minutes after 25 minutes of resuscitation effort. Data collection included electrocardiogram, arterial blood pressure, and arterial and mixed venous oxygen saturations. There was no significant difference in survival between the saline group (4/12, 33%) and lipid emulsion group (6/12, 50%; P > .05). Additionally, there was no significant difference between groups of surviving animals in the time to ROSC (P > .05). The combination of lipid emulsion and ACLS did not improve survival from bupivacaine- and hypoxia-induced cardiovascular collapse in unanesthetized swine.