Local Anesthetic Systemic Toxicity: A Review of Recent Case Reports and Registries

This review summarizes presenting features, management, and outcomes of local anesthetic systemic toxicity (LAST) from published cases and those submitted to online registries capturing use of intravenous lipid emulsion (ILE) therapy. The results of single-center and multicenter registries and epidemiologic studies complement this information. Between March 2014 and November 2016, 47 separate cases of LAST were described in 35 peer-reviewed articles. Local anesthetic systemic toxicity events occurred as a result of penile blocks (23%), local infiltration (17%), and upper/lower extremity, torso, and neuraxial blockade. Twenty-two patients (47%) were treated with ILE, and 2 patients (4.3%) died. During the same time period, 11 cases submitted to lipidrescue.org were treated with ILE and survived. The incidence of LAST reported in registries is 0.03% or 0.27 (95% confidence interval, 0.21-0.35) per 1000 peripheral nerve blocks (denominator of 251,325). Seizure (53% and 61% from case reports and registries, respectively) was the most common presenting feature.