Elaboração de proposta de protocolo para o uso da emulsão lipídica intravenosa no tratamento de intoxicação aguda por anestésicos locais envolvendo humanos

Abstract

Intravenous lipid emulsion (ELI) has been used in the treatment of acute intoxication by local anesthetics and other lipophilic drugs. The present work aimed the elaboration of a protocol proposal for the use of ELI in the treatment of acute intoxications caused by local anesthetics. A literature search was performed for in Medline, The Cochrane Library and Trip Database. A combination of specific keywords and MeSH terms were used: lipid, emulsion, "local anesthetic", toxicity, intravenous, "lipid emulsion", "fat emulsion", intralipid, arrest, rescue, resuscitation, antidote, "lipophilic drugs”, intoxication e “intravenous lipid". Were included meta-analysis, systematic review and randomized controlled clinical trials, focusing on the safety and efficacy associated with the use of ELI in the treatment of intoxications, published in the years 2013 to 2018. Other publications considered: guidelines for the use of ELI with indications, posology, administration, adverse effects and laboratory interferences found on sites of international toxicology and anesthesia associations, clinical toxicology book, Toxbase®, IBM Micromedex®, and Intralipid® product monograph (most commonly used lipid emulsion in poisonings). Based on the analysis of the publications selected, the proposal of a protocol for the use of ELI in acute systemic intoxications by local anesthetics should contemplate recommendations based on currently available clinical evidence, which are described below. The administration of ELI is recommended for local anesthetics intoxication in cardiac arrest and life-threatening toxicity, such as hemodynamic shock after other therapies fail. Specifically for bupivacaine, in cases of cardiac arrest, it is recommended as first-line therapy, after initiation of Advanced Cardiovascular Life Support. Therefore, the use of ELI should be evaluated with caution, considering the risks and benefits. The most commonly used formulation is Intralipid® 20%. The dose should consider a bolus dose of 1.5 mL/kg, followed by continuous infusion of 0.25 mL/kg/min. If necessary, the bolus could be repeated one or two more times within 5 min between doses and continuous infusion may be titrated according to the clinical response of the patient up to the infusion rate of 0.5 mL/kg/min. Respecting the maximum cumulative dose of 12 mL/kg, and the infusion time of 60 minutes. Potential adverse effects such as pancreatitis, fat overload syndrome, cardiac arrest, fatty embolism and others, furthermore laboratory interferences, as a consequence of lipemia, should be evaluated and considered in ELI use. Despite the growing enthusiasm of lipid emulsion use in local anesthetics acute systemic intoxications, the scientific evidence is not robust about ELI's recommendation as first-line treatment for all local anesthetics or all possible clinical situations