Methemoglobinemia after fiberoptic intubation in a patient with an unstable cervical fracture: A case report

Methemoglobinemia, a condition associated with cyanosis and diminished pulse oximetry values, has been reported after use of local anesthetics to facilitate fiberoptic intubation. The majority of reports in the literature detail this development during diagnostic procedures such as endoscopy and bronchoscopy. A case of methemoglobinemia in a multiple-injury patient with an unstable compressive-flexion injury of the cervical spine undergoing fiberoptic intubation is presented. A literature review of this entity is also presented. The patient underwent fiberoptic intubation using topical pharyngeal anesthetics before planned cervical corpectomy, strut grafting and instrumentation. He became acutely cyanotic with abruptly diminished pulse oximetry readings. Subsequent blood gas analysis demonstrated methemoglobinemia. Intravenous methylene blue administration led to an uncomplicated resolution of the condition. Surgeons and anesthesiologists who manage such patients should be aware of methemoglobinemia, a rare but potentially fatal complication related to topical airway anesthetics.