Systematic review of the effect of intravenous lipid emulsion therapy for non-local anesthetics toxicity.

BACKGROUND The use of intravenous lipid emulsion (ILE) therapy for the treatment of lipophilic drug toxicity is increasing. Despite this, the evidence for its effect in non-local anesthetic toxicity remains sparse. Furthermore, many case reports describe ILE use for substances in which no clear efficacy data exists. The American Academy of Clinical Toxicology established a lipid emulsion workgroup. The aim of this group is to review the available evidence regarding the effect of ILE in non-LA drug poisoning and develop consensus-based recommendations on the use of this therapy. METHODS A systematic review of the literature was performed to capture articles through 15 December 2014. Relevant articles were determined based upon a predefined methodology. Articles involving pre-treatment experiments, pharmacokinetic studies not involving toxicity, and studies not addressing antidotal use of ILE met pre-defined exclusion criteria. Agreement of at least two members of the subgroup was required before an article could be excluded. RESULTS The final analysis included 203 articles: 141 for humans and 62 for animals. These include 40 animal experiments and 22 case reports involving animal toxicity. There were three human randomized control trials (RCT): one RCT examined ILE in TCA overdose, one RCT examined ILE in various overdoses, and one study examined ILE in reversal of sedation after therapeutic administration of inhaled anesthesia. One observational study examined ILE in glyphosate overdose. In addition, 137 human case reports or case series were identified. Intravenous lipid emulsion therapy was used in the management of overdose with 65 unique substances. CONCLUSIONS Despite the use of ILE for multiple substances in the treatment of patients with poisoning and overdose, the effect of ILE in various non-local anesthetic poisonings is heterogenous, and the quality of evidence remains low to very low.