Hypocalcemia and Recurrent Laryngeal Nerve Injury after Thyroid Surgery

Tae, Kyung; Lee, Hyung Seok; Jeong, Yeon Gi; Kim, Ki Tae; Lee, Seong Hwan; Park, Young Su; Ahn, You Hern

Abstract

BACKGROUND AND OBJECTIVES: The main indication for thyroidectomy are thyroid cancer, multinodular goiter, and Graves' disease. Most important complications of thyroidectomy are recurrent laryngeal nerve injury and hypoparathyroidism. The risk of complication depends on the extent of the operation, and skill and experiences of surgeon. The purpose of this study is to determine the incidence and predictive factors for complication after thyroidectomy. MATERIALS AND METHOD: We examined the records of 233 patients who underwent thyroidectomy at the Department of Otolaryngology, Hanyang University from 1994 to 2001. The postoperative complication including hypocalcemia, recurrent laryngeal nerve palsy and hematoma was identified and analysed. The rate of recurrent laryngeal nerve palsy was calculated on the number of nerve at risk of injury. There were 135 unilateral and 98 bilateral procedures. Nerves at risk is 329. The hypocalcemia was defined as a ionized calcium fell below 1.01 mEq/L.
RESULTS
Among 233 patients, 3 patients (1.3%) had permanent hypocalcemia and 57 patients (24.5%) had transient hypocalcemia. According to surgical procedure total thyroidectomy with neck dissection was associated with an increased risk of transient hypocalcemia (63.6%). The incidence of temporary and permanent recurrent laryngeal nerve palsy was 0.9% (3/329) and 0.3% (1/329), respectively. The postoperative hematoma occurred in 7 patients (3%).
CONCLUSION
The most frequent complication after thyroidectomy is transient hypocalcemia. Based on our results, thyroidectomy is a relatively safe procedure. Complications can be kept to a minimum by a through knowledge of the anatomy, by understanding thyroid pathology, and by meticulous hemostasis and delicate surgical technique.