[Identification of the recurrent nerve in thyroid surgery. Technical note]

The authors report an experience of 1800 surgical operations for thyroid diseases executed, with identification of the recurrent laryngeal nerve in all cases, from 1988 to 1992, and analyse the various causes of recurrent laryngeal nerve injury. This complication of thyroid surgery is not completely avoidable, in spite of an extremely accurate surgical technique. In most instances of injury to one of the recurrent laryngeal nerves during thyroidectomy, the surgeon can confirm that the recurrent laryngeal nerve was not sectioned during the operation. This fact demonstrates that often the recurrent laryngeal nerve injury is due not to a section but to a stretching, a compression, an ischemia of the nerve. The recurrent laryngeal nerve injury may be due to a mistake in surgical technique: the ligation of the inferior pole vessels before identifying the recurrent laryngeal nerve; a mistake in hemostasis maneuvers; excessive aspiration near to the nerve; an excessive traction of the recurrent laryngeal nerve during the medial traction of the thyroid lobe with a stretching of the nerve; an excessive dissection of the nerve with ischemia. Other causes that make easier the recurrent laryngeal nerve injury are, anatomic variations of the nerve; extension of the surgical operation; histologic findings.