Efficacy of SLN Block for Chronic Cough

Medical University of South Carolina17 enrolled

Overview

This is a research study to find out if superior laryngeal nerve blocks are an effective way to reduce cough when compared to placebo (a substance without any medical value). Eligibility for the study include the following: age \>18, cough history suggestive that the nerve to the voice box is overactive, non-smoker, Patients will be followed over time and assigned to either the treatment or placebo group at random. The treatment would be four superior laryngeal nerve blocks and the placebo would be four saline injections (the inactive substance). Study team will measure if the injection improved cough and ask patients to keep a log of symptoms and fill out questionnaires at each visit. After the four injections, patients will follow up in 3 months to see if cough has returned and if so, how severe the cough is.

Study Type

INTERVENTIONAL

Allocation

RANDOMIZED

Purpose

HEALTH_SERVICES_RESEARCH

Masking

SINGLE

Enrollment

Conditions

Cough Superior Laryngeal Nerve Block Neurogenic Cough

Superior laryngeal nerve blockPROCEDURE

Injection of either the steroid-lidocaine mixture or placebo through the skin around where the superior laryngeal nerve is located on the neck. The procedure lasts 5 minutes and is done in the clinic.

Injection of placebo (saline)PROCEDURE

Superior laryngeal nerve block using 1mL of saline as the injection.

Injection of steroid-lidocaine mixturePROCEDURE

Superior laryngeal nerve block using 1mg 1:1 triamcinolone 40mg: 1% lidocaine with 1:200000 epinephrine as the injection.

Eligibility

Sex: ALLMin age: 18 YearsHealthy volunteers:

Medical Language ↔ Plain English

Inclusion Criteria: * History consistent with neurogenic cough * Exclusion of other etiologies (see exclusion criteria) * Age ≥ 18 Exclusion Criteria: * Current neuromodulating medication use * Untreated other etiologies of cough: Current smoker Current ACE/ARB use Abnormal PFTs within 6 months Uncontrolled OSA Abnormal CXR within 6 months RSI \> 13 or RFS \>11 AND workup positive for GERD (esophagram, 24-hour pH probe, manometry, EGD)

Outcomes

Primary Outcomes

Change in Cough Severity

Patient will complete the Leicester Cough Questionnaire at each visit. This is a validated survey that measures 3 domains (physical, psychological and social). The total score range is 3-21 and domain scores range from 1-7; a higher score indicates a better quality of life.

Time frame: Change from Baseline to 3 months

Secondary Outcomes

Subjective Improvement in Cough

Improvement was defined as a 'yes' response at any time point during the study (1-4 weeks or 3 months post-treatment). The reported value reflects the total number of participants who reported improvement at any time point.

Time frame: Baseline, 1-4 weeks post-injection, and 3 months post-treatment

Summed Daily Change in Subjective Cough Severity

Participants rate cough severity on a 0-15 visual analogue scale. Scores are recorded daily and analyzed using regression. Higher scores indicate greater severity. VAS is a 0-15 scale completed daily by participants. Severity is measured using a ruler to determine percentage along the scale. Scores were analyzed using regression models to assess trends over time.

Time frame: Daily for 3 months post-injection