Unilateral sublingual nerve paralysis after laryngeal mask airway in a patient with congenital heart disease: a case report

Laryngeal masks are widely used by anesthesiologists in clinical practice because of their advantages of no tracheal injury, minimal airway stimulation, limited airway tissue invasion, and easy implantation and airway establishment. We herein describe a patient with congenital heart disease who developed unilateral sublingual nerve paralysis after application of a laryngeal mask airway. The patient reported perioral numbness and exhibited unclear speech and slight right deviation of the tip of the tongue after surgery. On physical examination, the patient had normal muscle strength, symmetrical frontal lines, normal occlusion, and a normal nasolabial groove. We performed head computed tomography and computed tomography angiography to rule out cerebrovascular disease, and no abnormalities were found. The patient's imaging findings and clinical symptoms suggested unilateral right sublingual nerve palsy. After active treatment, the patient's symptoms improved by 75% on the third postoperative day and by 90% on the fifth postoperative day. Despite the extremely low incidence of sublingual nerve palsy after application of a laryngeal mask airway, anesthesiologists should be aware of this complication. Although the nerve palsy can resolve spontaneously, the nerve damage may be permanent.