Resuscitation strategies from bupivacaine-induced cardiac arrest

Objectives: Local anesthetic (LA) intoxication with cardiovascular arrest is a potential fatal complication of regional anesthesia. Lipid resuscitation has been recommended for the treatment of LA‐induced cardiac arrest. Aim of the study was to compare four different rescue regimens using epinephrine and/or lipid emulsion and vasopressin to treat cardiac arrest caused by bupivacaine intoxication. Methods: Twenty‐eight piglets were randomized into four groups (4 × 7), anesthetized with sevoflurane, intubated, and ventilated. Bupivacaine was infused with a syringe driver via central venous catheter at a rate of 1 mg·kg^?1·min^?1 until circulatory arrest. Bupivacaine infusion and sevoflurane were then stopped, chest compression was started, and the pigs were ventilated with 100% oxygen. After 1 min, epinephrine 10 μg·kg^?1 (group 1), Intralipid^® 20% 4 ml·kg^?1 (group 2), epinephrine 10 μg·kg^?1 + Intralipid^® 4 ml·kg^?1 (group 3) or 2 IU vasopressin + Intralipid^® 4 ml·kg^?1 (group 4) were administered. Secondary epinephrine doses were given after 5 min if required. Results: Survival was 71%, 29%, 86%, and 57% in groups 1, 2, 3, and 4. Return of spontaneous circulation was regained only by initial administration of epinephrine alone or in combination with Intralipid^®. Piglets receiving the combination therapy survived without further epinephrine support. In contrast, in groups 2 and 4, return of spontaneous circulation was only achieved after secondary epinephrine rescue. Conclusions: In cardiac arrest caused by bupivacaine intoxication, first‐line rescue with epinephrine and epinephrine + Intralipid^® was more effective with regard to survival than Intralipid^® alone and vasopressin + Intralipid^® in this pig model.