Morbidity and mortality from local anesthetics: localized and systemic toxicity.
PURPOSE OF THE REVIEW: Local anesthetics remain vital to modern medicine, yet their narrow therapeutic window continues to result in complications. This review synthesizes recent literature to define the current landscape of local anesthetic-associated adverse events. RECENT FINDINGS: Perioperative mortality attributable to local anesthetics persists despite sustained safety initiatives and professional society recommendations. Pharmacovigilance and case data identify lidocaine (oropharyngeal, topical, and via local infiltration) as the predominant contributor to adverse outcomes, including death. Local anesthetic systemic toxicity remains an issue, with a recent shift in epidemiology: an increasing proportion of toxic events originates from surgeon- and proceduralist-administered analgesia. Anesthesiologist-controlled methods also cause toxicity via catheter-based delivery and nerve blocks in highly vascular regions. Localized toxicity in the form of high neuraxial contributes to morbidity, with recent reviews reinforcing known risk factors; whereas localized neurotoxicity appears less troublesome when managed appropriately. SUMMARY: The cumulative evidence identifies shifts in the patterns of systemic and localized toxicities. Bupivacaine-based peripheral nerve blocks no longer represent the principal cause of complications because of the advent of ultrasound guidance and lipid emulsion therapy. In contrast, high neuraxial techniques persist as a cause of morbidity, accompanied by intravenous/oropharyngeal lidocaine, proceduralist-administered local infiltration analgesia, and catheter-based delivery.