2018 Section 6 - Laryngology, Voice Disorders, and Bronchoesophalogy

Reprinted by permission of Head Neck. 2016; 38(6):811-819.

PRACTICE GUIDELINES

Laryngeal examination in thyroid and parathyroid surgery: An American Head and Neck Society consensus statement

AHNS Consensus Statement

Catherine F. Sinclair, MD, 1 * Jeffrey M. Bumpous, MD, 2 Bryan R. Haugen, MD, 3 Andres Chala, MD, 4 Daniel Meltzer, MD, 5 Barbra S. Miller, MD, 6 Neil S. Tolley, MD, 7 Jennifer J. Shin, MD, 8 Gayle Woodson, MD, 9 Gregory W. Randolph, MD 10

1 Department of Head and Neck Surgery, Icahn School of Medicine at Mount Sinai, New York, NY, 2 Department of Otolaryngology, University of Louisville, Louisville, Kentucky, 3 University of Colorado School of Medicine, Aurora, CO, 4 University of Caldas, Manizales, Caldas, Colombia, South America, 5 Mount Sinai, New York, New York, 6 Department of Surgery, University of Michigan, Ann Arbor, Michigan, 7 Department of Surgery, Imperial College of London, London, United Kingdom, 8 Harvard, Boston, Massachusetts, 9 Depart- ment of Otolaryngology, Southern Illinois University School of Medicine, Carbondale, Illinois, 10 Harvard Medical School, Massachusetts Eye and Ear Infirmary, Boston, Massachusetts.

Accepted 29 December 2015 Published online 11 March 2016 in Wiley Online Library (wileyonlinelibrary.com). DOI 10.1002/hed.24409

This American Head and Neck Society (AHNS) consensus statement dis- cusses the techniques of laryngeal examination for patients undergoing thyroidectomy and parathyroidectomy. It is intended to help guide all clinicians who diagnose or manage adult patients with thyroid disease for whom surgery is indicated, contemplated, or has been performed. This consensus statement concludes that flexible transnasal laryngos- copy is the optimal laryngeal examination technique, with other techni-

ques including laryngeal ultrasound and stroboscopy being useful in selected scenarios. V C 2016 Wiley Periodicals, Inc. Head Neck 38: 811– 819, 2016 KEY WORDS: thyroidectomy, voice, larynx, recurrent laryngeal nerve, vocal fold paralysis

INTRODUCTION The larynx with its complex neural supply is at the center of the thyroid and parathyroid operative field. Postopera- tive voice changes are one of the most feared complica- tions of thyroid and parathyroid surgery and recurrent laryngeal nerve (RLN) injury is one of the most common causes of postoperative voice change. Rates of RLN injury have traditionally been quoted in small percentages and have likely been significantly underreported because of variable postoperative laryngeal examination practices and reporting bias from expert units with lower rates of complications because of higher caseload volume. Mod- ern series comprehensively analyzing occurrence of RLN paralysis after thyroidectomy suggest rates of nearly 10%. 1,2 Postoperative voice changes can also occur because of injury to the external branch of the superior laryngeal nerve (EBSLN), resulting in diminished vocal projection and inability to attain higher vocal registers, and from nonneural pathology, such as direct cricothyroid muscle dysfunction and regional soft tissue changes. A number of recent large series have quoted subjective post-

thyroidectomy voice complaints in 30% to 87% of patients. 3–6 Subtle voice changes are not easily volunteered by patients and may be difficult for clinicians to detect. Also, importantly, there is a significant divergence between voice symptoms and objective vocal cord function. Indeed, the sensitivity of voice change in predicting vocal cord paraly- sis ranged from 33% to 68% in 2 recent studies. 7,8 Thus, vocal cord paralysis may be present without significant vocal symptoms (and vice versa) because of factors, such as variable contralateral cord function, variable contralat- eral cord location, and variability in ipsilateral cord inner- vation and function. This discrepancy between subjective and objective findings provides a rationale for the inclusion of glottic examination in all patients, both preoperatively and postoperatively if we endeavor to accurately measure neural quality outcomes of thyroid surgery. Preoperative recognition of vocal cord paralysis is essential for preoper- ative surgical planning as an RLN found invaded at surgery by a thyroid malignancy is managed based on knowledge of its preoperative function. Also, from a medicolegal viewpoint, preoperative assessment of vocal cord function is necessary before assuming responsibility for vocal cord paralysis found postoperatively. Many thyroid surgeries are performed by surgeons who perform fewer than 5 to 10 cases a year and there is a known correlation between workload and outcomes in

* Corresponding author: C. Sinclair, Department of Head and Neck Surgery, Otolaryngology, Mount Sinai St. Luke’s Roosevelt Hospitals, 1111 Amsterdam Avenue, New York, NY 10019. E-mail: casinclair@chpnet.org

HEAD & NECK—DOI 10.1002/HED JUNE 2016

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