Carbon Dioxide Embolism During Transoral Endoscopic Thyroidectomy Vestibular Approach: A Case Report.

Carbon dioxide (CO2) embolism is a rare but serious complication during transoral endoscopic thyroidectomy vestibular approach (TOETVA). We report the case of a 58-years-old Thai woman with hypertension and hyperthyroidism who underwent TOETVA for completion thyroidectomy. Intraoperatively, injury to the anterior jugular vein likely caused CO2 embolism, indicated by a sudden rise in end-tidal CO2. The procedure was converted to open surgery. Postoperatively, she developed seizures, left-sided weakness, and confusion. Imaging confirmed cerebral gas embolism, and echocardiography revealed a patent foramen ovale. She was treated with antiepileptic medications and hyperbaric oxygen therapy, resulting in full neurological recovery. This case shows that CO2 embolism can still occur during TOETVA at low insufflation pressure, following anterior jugular vein injury. A sudden end-tidal CO2 change may be an early clue, and early recognition with prompt hyperbaric oxygen therapy (HBOT) can help prevent lasting neurologic deficits.