Essentials for Vocal Care During and After Thyroid Surgery

Educational Objectives

The goal of this program is to improve management of vocal care in patients undergoing thyroid surgery. After hearing and assimilating this program, the clinician will be better able to:

1. Use intraoperative nerve monitoring to reduce the incidence of nerve damage during thyroid surgery.
2. Select treatments for relief of throat pain and chronic cough after thyroid surgery.

Summary

Anatomy: the vocal folds are structures that open and close to aid in phonation and swallowing; the tracheal airway is situated distal to the vocal fold; laryngoscopy is used to assess vocal fold mobility (ie, adduction and abduction); videostroboscopy is a specific examination that assesses vocal fold mobility and pliability, which allow for the production of resonant sound; the vagus nerve splits into a sensory branch which enters the larynx and a second nerve which enters to the cricothyroid muscle in the anterior part of the larynx; the cricothyroid muscle gives the vocal folds their tensile strength and permits pitch control; the motor function of the vocal fold is controlled by the recurrent laryngeal nerve, which arises inferiorly from the vagus and travels superiorly up to the larynx; vocal fold paralysis may be caused by tumor, thyroid malignancy, or iatrogenic injury during surgery

Nerve injury after thyroid surgery: patients may present postoperatively with a breathy voice difficulty; the risk for aspiration increases because of poor vocal fold closure during swallowing; immediate intervention is required; lateral vocal fold immobility is one of the most common postoperative complications; unilateral vocal immobility may be transient (≤40%) or permanent (≤20%); bilateral vocal fold immobility (≤2%) may lead to significant respiratory distress and require tracheostomy; complications cause significant healthcare burden; patients may recover within 3 to 6 mo in cases in which the recurrent laryngeal nerve remains intact; the prognosis is poor if complete recovery does not occur by 12 mo; ≤75% of patients with one vocal fold have swallowing issues, ≤44% of patients report aspiration, and ≤80% of patients report dysphonia; a specific metric for quality of life is not available

Management: guidelines from the American Academy of Otolaryngology, the American Head and Neck Society, and European societies advise that patients with previous head, neck, or chest surgery or a history of voice changes should undergo laryngeal examination before thyroid surgery; patients should undergo laryngoscopy in cases in which there is a risk for nerve transection or injury after surgery

Intraoperative nerve monitoring: an endotracheal tube with electrodes is used for electromyographic recording of the vocal muscle or thyrohyoid muscle; nerve monitoring aids in the intraoperative assessment of the integrity of the vagus nerve and recurrent laryngeal nerve; standardization is possible with use of specific endotracheal tubes; a neurophysiologically intact nerve may be intraoperatively stimulated to provide feedback, which aids in determining postoperative vocal fold immobility; nerve monitoring may be used to identify the nerve before surgery and assess the functional integrity of tissues that have been damaged by cancer; analysis of clinical data does not show significant differences in nerve injuries with the use of nerve monitoring; methods of monitoring vary; a reduction in nerve signal following surgery suggests that vocal fold immobility may occur

Evaluation: laryngeal dysfunction may be motor or sensory; complaints should be categorized to identify the damaged nerve; vocal fatigue is linked to motor dysfunction, which may result from a partial recurrent laryngeal nerve issue; superior laryngeal nerve damage may cause difficulty in fine tuning of the voice; partial neuropraxia may cause glottic fold insufficiency

Management: speech therapy is recommended for partial neuropraxia; in-office injection of fillers may help provide glottic closure in patients with vocal fold immobility; injection is carried out under local anesthesia with lidocaine; the needle is placed over the tongue and filler is injected into the vocal fold to close gaps in the glottis; fillers may temporarily provide optimal voice outcomes for patients; irritable larynx or functional dysphonia is associated with tickling sensation, cough, and swallowing issues (dysphagia); management of functional symptoms requires a multidisciplinary approach; a superior laryngeal nerve block is suitable for patients with throat pain, tickling, and irritation; chronic cough from external stimuli is managed with in-office lidocaine and corticosteroids

Quality of life: the quality of life of the patient in terms of their voice should be assessed before and after surgery; the clinician may refer the patient to a speech therapist and otolaryngologist for early management of symptoms; surgeons must take intraoperative findings into account when determining postoperative outcomes; patients who experience changes in amplitude during surgery need to be monitored for laryngeal dysfunction and given continuity of care; "quality of life metrics" for voice impairment from thyroidectomy need to be developed; a standardized laryngeal examination is necessary to discuss voice outcomes with patients

Readings

Cirocchi R, Arezzo A, D'Andrea V, et al. Intraoperative neuromonitoring versus visual nerve identification for prevention of recurrent laryngeal nerve injury in adults undergoing thyroid surgery. Cochrane Database Syst Rev. 2019;1(1):CD012483. Published 2019 Jan 19. doi:10.1002/14651858.CD012483.pub2; Dhahri AA, Ahmad R, Rao A, et al. Use of Prophylactic steroids to prevent hypocalcemia and voice dysfunction in patients undergoing thyroidectomy: A randomized clinical trial. JAMA Otolaryngol Head Neck Surg. 2021;147(10):866-870. doi:10.1001/jamaoto.2021.2190; Dhillon VK. Longitudinal follow-up of superior laryngeal nerve block for chronic neurogenic cough. OTO Open. 2021;5(1):2473974X21994468. Published 2021 Feb 16. doi:10.1177/2473974X21994468; Huang TY, Yu WV, Chiang FY, et al. How the severity and mechanism of recurrent laryngeal nerve dysfunction during monitored thyroidectomy impact on postoperative voice. Cancers (Basel). 2021;13(21):5379. Published 2021 Oct 27. doi:10.3390/cancers13215379; Jin Y, Zhou X, Chen X, et al. Internal branch of superior laryngeal nerve block by dexamethasone alleviates sore throat after thyroidectomy: a randomized controlled trial. Eur Arch Otorhinolaryngol. 2022;279(12):5877-5884. doi:10.1007/s00405-022-07513-5; Liao LJ, Wang CT. Management of unilateral vocal fold paralysis after thyroid surgery with injection laryngoplasty: State of art review. Front Surg. 2022;9:876228. Published 2022 Apr 6. doi:10.3389/fsurg.2022.876228; Pace-Asciak P, Russell JO, Tufano RP. Improving voice outcomes after thyroid surgery and ultrasound-guided ablation procedures. Front Surg. 2022;9:882594. Published 2022 May 4. doi:10.3389/fsurg.2022.882594; Tian H, Pan J, Chen L, et al. A narrative review of current therapies in unilateral recurrent laryngeal nerve injury caused by thyroid surgery. Gland Surg. 2022;11(1):270-278. doi:10.21037/gs-21-708; Wang JJ, Huang TY, Wu CW, et al. Improving voice outcomes after thyroid surgery - review of safety parameters for using energy-based devices near the recurrent laryngeal nerve. Front Endocrinol (Lausanne). 2021;12:793431. Published 2021 Nov 24. doi:10.3389/fendo.2021.793431.

Disclosures

For this program, members of the faculty and planning committee reported nothing relevant to disclose.

Acknowledgements

Dr. Dhillon was recorded at The USC Peter A. Singer Thyroid Symposium 2023, held June 3, 2023, in Los Angeles, CA, and presented by the Keck School of Medicine of the University of Southern California. For information about upcoming CME activities from this presenter, please visit keckusc.cloud-cme.com. Audio Digest thanks the speakers and the presenters for their cooperation in the production of this program.

CME/CE INFO

Accreditation:

The Audio- Digest Foundation is accredited by the Accreditation Council for Continuing Medical Education to provide continuing medical education for physicians.

The Audio- Digest Foundation designates this enduring material for a maximum of 1.00 AMA PRA Category 1 Credits™. Physicians should claim only the credit commensurate with the extent of their participation in the activity.

Audio Digest Foundation is accredited as a provider of continuing nursing education by the American Nurses Credentialing Center's (ANCC's) Commission on Accreditation. Audio Digest Foundation designates this activity for 1.00 CE contact hours.

Lecture ID:

OT562401

Expiration:

This CME course qualifies for AMA PRA Category 1 Credits™ for 3 years from the date of publication.

Instructions:

To earn CME/CE credit for this course, you must complete all the following components in the order recommended: (1) Review introductory course content, including Educational Objectives and Faculty/Planner Disclosures; (2) Listen to the audio program and review accompanying learning materials; (3) Complete posttest (only after completing Step 2) and earn a passing score of at least 80%. Taking the course Pretest and completing the Evaluation Survey are strongly recommended (but not mandatory) components of completing this CME/CE course.

Estimated time to complete this CME/CE course:

Approximately 2x the length of the recorded lecture to account for time spent studying accompanying learning materials and completing tests.