Comparison of epinephrine vs lipid rescue to treat severe local anesthetic toxicity - an experimental study in piglets

Summary Objectives: Local anesthetic (LA) intoxication with severe hemodynamic compromise is a potential catastrophic event. Lipid resuscitation has been recommended for the treatment of LA‐induced cardiac arrest. However, there are no data about effectiveness of Intralipid® for the treatment of severe cardiovascular compromise prior to cardiac arrest. Aim of this study was to compare effectiveness of epinephrine and Intralipid® for the treatment of severe hemodynamic compromise owing to bupivacaine intoxication. Methods: Piglets were anesthetized with sevoflurane, intubated, and ventilated. Bupivacaine was infused with a syringe driver via a central venous catheter at a rate of 1 mg·kg−1·min−1 until invasively measured mean arterial pressure (MAP) dropped to 50% of the initial value. Bupivacaine infusion was then stopped, and epinephrine 3 μg·kg−1 (group 1), Intralipid® 20% 2 ml·kg−1 (group 2), or Intralipid® 20% 4 ml·kg−1 (group 3) was immediately administered. Survival, hemodynamic course, and ETCO2 were recorded. Results: Twenty‐one piglets (3 × 7), with median age of 26 days (19–43) and weighing 4.9 kg (4.3–5.8), were investigated. All animals in group 1 (100%) but only four of seven (57%) piglets in group 2 and group 3, respectively, survived. Normalization of hemodynamic parameters (HR, MAP) and ETCO2 was fastest in group 1 with all piglets achieving HR and MAP values at or above baseline within 1 min. Conclusion: For the treatment of severe hemodynamic compromise owing to bupivacaine intoxication in piglets, first‐line rescue with epinephrine was more effective than Intralipid® with regard to survival as well as normalization of hemodynamic parameters and ETCO2.