Acoustic characteristics of patients undergoing short-term endotracheal intubation with or without thyroidectomy who had no nerve injury

Kang, Bo Hyeon; Heo, Seong Cheol; Yoo, Seung Joo; Kim, Sang Yoon; Nam, Soon Yuhl

Abstract

BACKGROUND AND OBJECTIVES
We carried out an acoustic analysis to investigate the phonatory characteristics of patients undergoing short-term endotracheal intubation with or without thyroidectomy, and who had no nerve injury.
MATERIALS AND METHODS
The patients were divided into two groups, one undergoing thyroidectomy (39 cases) and the other not undergoing thyroidectomy (25 cases). All patients of the thyroidectomy group had undergone thyroidectomy using general anesthesia with endotracheal intubation. All patients of the other group had undergone chronic ear surgery with the same anesthetic method and duration. For the evaluation of voice, preoperative and postoperative acoustic analyses were done.
RESULTS
On the acoustic analysis of thyroidectomy group, jitter, shimmer and the vocal range were significantly increased at one day after thyroidectomy. But one month after thyroidectomy, these changes return to statistically insignificant increments, except for shimmer and the vocal range. These acoustical changes were not related to the extent of surgery between total thyroidectomy and hemithyroidectomy. In comparison with acoustical changes after short-term endotracheal intubation, the change of jitter and shimmer of thyroidectomy group did differ significantly.
CONCLUSION
Voice alteration after thyroidectomy without nerve injury may be associated with the disturbance of the prelaryngeal musculature. This voice changes emphasize the importance of the extralaryngeal skeleton for pitch control and early intensive speech therapy, especially in patients who need their voice professionally.