Infiltration of nanocarbon suspension into the tracheal cavity during surgical treatment of papillary thyroid carcinoma: a case report

Cervical lymph node metastasis in patients with differentiated thyroid cancer affects postoperative recurrence and survival. Hypoparathyroidism is caused by parathyroid gland injury during thyroidectomy. Carbon nanoparticles can trace stained lymph nodes, aiding in thorough dissection of lymph nodes in the operation area. To reduce postoperative occurrence of hypoparathyroidism, the parathyroid glands and their functions (identified by negative imaging induced by carbon nanoparticles) are retained in situ. However, the safety and adverse effects of nanocarbon suspension in thyroid surgery have rarely been evaluated. In this report, we describe a patient with thyroid cancer who had carbon secretions in the trachea caused by nanocarbon suspension when tracheal intubation was performed under general anesthesia, and the inflatable balloon surface of the tracheal tube was covered with these secretions. The patient recovered without fever, cough, phlegm production, chest pain, hoarseness, or hypocalcemia-induced convulsions. No consensus has yet been reached on the most appropriate injection site, depth, dose, or waiting time for nanocarbons in thyroid cancer surgery. We believe that nanocarbon suspension is safe for use in thyroid cancer surgery, but the most appropriate injection depth should be based on the thickness of the thyroid gland tissue to avoid deep injection into the trachea.