Superior Laryngeal Nerve Block May Be a Viable Treatment Option for Neurogenic Cough

by Linda Kossoff •

How do procedural therapies such as SLN block compare to other established pharmacologic and nonpharmacologic treatments for neurogenic cough (NC)?

BOTTOM LINE

Procedural therapy, including SLN block, should be considered in the armamentarium of NC treatments.

BACKGROUND: Triggered by innocuous stimuli such as laughing or talking, NC is a prevalent condition that negatively affects quality of life. Although evidence-based guidelines on NC treatment established gabapentin as the gold standard, a full understanding of the condition is relatively nascent. SLN block has emerged as a novel treatment for NC.

COMMENT: Within this study, the authors aim to describe the clinical effectiveness of pharmacologic and nonpharmacologic interventions for neurogenic cough, particularly how superior laryngeal nerve (SLN) block compares to established pharmacologic treatments. The results of this study support SLN block as a potential treatment for neurogenic cough, particularly in patients who are refractory to, or intolerant of, the side effects of medical therapy. Furthermore, the success of the SLN block suggests efficacy of a more permanent option: SLN transaction. —Albert L. Merati, MD

STUDY DESIGN: Systematic review and meta-analysis.

SETTING: Department of Otolaryngology–Head and Neck Surgery, Washington University in St. Louis, Mo.

SYNOPSIS: Researchers analyzed selected clinical trials, cohort studies, case-control studies, and case series with >10 adults with NC who received any pharmacologic or nonpharmacologic treatment. Neurogenic cough was defined as cough persisting >8 weeks after ruling out other etiologies, or after failure of supervised therapeutic trials for the most common causes of persistent cough. There were 2,408 patients (majority female, aged 60-69) with NC included. Of these, 77% were treated with medical therapy (neuromodulating drugs, tricyclic antidepressants, opioids, macrolide antibiotics, proton pump inhibitors, and investigational drugs), 19% with speech therapy (cough education, suppression techniques, and stress or anxiety counseling), 1% with both medical and speech therapy, and 3% with procedural therapy (SLN block, bilateral thyroarytenoid BTX injections, and vocal fold augmentation). Meta-
analysis of results was conducted using patient-reported outcome measures. Most interventions demonstrated improvement in cough, although medical interventions had the highest rate of adverse events. Such events for SNL block were low. Study limitations included lack of direct comparisons between intervention types due to the heterogeneity of included study designs and lack of long-term follow-up among most reviewed studies.

CITATION: Wamkpah NS, Peterson AM, Lee JJ, et al. Curbing the cough: Multimodal treatments for neurogenic cough: A systematic review and meta-analysis [published online ahead of print October 21, 2020]. Laryngoscope.