Greater cervical nerve block with bupivacaine resulting in neurotoxicity: A case report

Background

Local anesthetics are critical in the management of acute and chronic pain in various procedures and medical specialties. Their anesthetic properties derive from the ability to reversibly block sodium channels embedded within nerve fibers, and thus inhibit the conduction of painful stimuli from an affected area. In supratherapeutic dosing, local anesthetic toxicity is directly related to the drug's propensity to distribute systemically. Onset and amplitude of toxicity may be increased in the setting of inadvertent intra-circulatory injection. One toxic manifestation is the direct inoculation of local anesthetics within the central nervous system (CNS).

Case report

We present the case of a 34-year-old-female with neurotoxicity secondary to bupivacaine injection during a greater occipital nerve block. Emergent management of the patient required intubation, seizure control, and intravenous lipid emulsion therapy.

Why should an emergency physician be aware of this?

Direct central nervous system (CNS) toxicity from local anesthetics leads to rapid clinical decline and the need for extensive immediate resuscitative efforts. Early in the resuscitation, emergency physicians must recognize that the symptoms of local anesthetic toxicity require prompt specialty consultation with medical toxicologists and treatment with intralipid therapy to help reduce morbidity and mortality. Knowledge of toxic doses of local anesthetic and the dose related toxic effects can prompt recognition of either direct CNS or intra-vessel injection.