NCT05696184 · Medical College of Wisconsin
Mechanisms Preventing Pharyngeal Reflux
What this study is about
The overall goal is to define and characterize the manometric characteristics of UES incompetence associated with objectively documented pharyngeal reflux. The investigators will use endoscopic reflux detection as gold standard.
View original scientific description
The overall goal is to define and characterize the manometric characteristics of UES incompetence associated with objectively documented pharyngeal reflux. The investigators will use endoscopic reflux detection as gold standard.
Interventions
DIAGNOSTIC_TEST
Concurrent manometry/impedance/pH with video pharyngo-laryngoscopy
Combined manometric/impedance/pH recording: we will use combined solid-state high-resolution manometry and impedance catheter with 36 circumferential pressure sensors, spaced 1 cm apart, 18 impedance sensor couplets spaced 2 cm apart, 3 pH sensors spaced 7 and 10 cm respectively. The catheter will be introduced trans-nasally. Concurrent video-pharyngo-laryngoscopy: to monitor concurrently the pharynx and larynx for entry of simulated refluxate we will use a laryngo-pharyngo-scope passed through the other nostril and positioned within the pharynx such that the UES inlet, vocal cords and pyriform sinuses are visualized. The laryngo-pharyngo-scope images will be synchronized with manometric/impedance/pH recordings by importing and superimposing the endoscopic images onto high resolution manometric recordings. A specially designed timer will be superimposed on the video images for durational analyses of endoscopic images.
DIAGNOSTIC_TEST
Slow and rapid intra-esophageal infusion
A 3 mm outer diameter injection tube will be placed through the nose in a fashion that the injection port will be located 5-7cm above the manometrically determined upper border of lower esophageal sphincter (LES). With this arrangement gastroesophageal reflux events will be simulated by intra-esophageal injection of body temperature1/2 normal saline (its ionic nature helps impedance recording and identification of intra-esophageal distribution), 0.1 N HCl. Infused liquid will be colored green using food dye for ease of recognition of pharyngeal reflux. Esophageal clearance will be verified by the presence of an effective peristalsis and return of intra-esophageal impedance and pressure to baseline. Endoscopic views of pharynx will be watched carefully during infusions. At the first sign of reflux, perfusion will be stopped, and participants will be instructed to swallow to avoid any potential airway compromise.
Primary outcome measures
Pressure Data Analysis
Time frame: During simulated reflux perfusion of the esophagus
All pressure measurements will be recorded at a 35HZ frequency and measured in reference to the atmospheric pressure UES and LES pressures will be measured utilizing the e-sleeve function of the manometric analysis software. All UES, LES and esophageal baseline pressures will be measured as peaks and troughs over 3 tidal volume respiratory cycles at stable resting conditions when no pharyngeal, gastric, esophageal, UES or LES events are present. Type, frequency, amplitude, onset, and duration of the UES response along with the LES and esophageal body response will be recorded.
Videoendoscopic data analysis
Time frame: During simulated reflux perfusion of the esophagus
Onset of the entry of colored refluxate into the pharynx though the UES inlet will be determined and correlated with the UES, esophageal and LES pressure phenomena, impedance and pH events. Endoscopic documentation of pharyngeal reflux will be considered the gold standard and impedance and pH data will be compared to it.
Who can participate
This study lists these criteria on ClinicalTrials.gov. A study coordinator reviews eligibility during screening — this page does not determine whether you qualify.
Inclusion criteria
- Age 18 to 85
- GERD patients with complaints of regurgitation and supra-esophageal symptoms will be included and recruited from our GI \& Otolaryngology clinics
- GERD patients without complaint of supra-esophageal symptoms and regurgitation will be included and recruited from our GI \& Otolaryngology clinics
- Asthma patients with and without supra-esophageal symptoms will be included and recruited from clinics affiliated with Medical College of Wisconsin. Asthma patients with the following classifications of asthma severity will be included: intermittent, mild persistent, moderate persistent, and severe persistent (as long as no acute asthma exacerbation at the time of the study)
- Patient definition will be based on position statement and technical reviews of the American Gastroenterological Association and Montreal definition and classification of gastroesophageal and reflux disease (Am J Gastroenterol. 2006;101:1900-1920).
- SERD is defined as patients on long term acid suppressive therapy complaining of persistent regurgitation along with supra-esophageal manifestations such as burning throat, asthma, chronic cough, or hoarseness. Patients will be screened by Reflux Symptom Index \> 13.
- Barrett's esophagus patients will be recruited based on histological diagnosis from previous endoscopic biopsy that will be found using the clinical database warehouse.
Exclusion criteria
- Age \<18 or \>85
- Active alcohol or drug abuse
- History of ear, nose, throat and pulmonary diseases suspected of being GERD induced
- History of head and neck malignancy and chemo-radiation therapy to the head and neck
- Unable to give consent
- Pregnant women (see justification in the Women and Minority Inclusion in Clinical Research section)
- History of allergy to Lidocaine for nasal topical anesthesia
- Allergy to green food dye
- Asthma patients with an acute asthma exacerbation with symptoms including breathlessness, wheezing, and chest tightness
Where
- Milwaukee, Wisconsin
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Frequently asked questions
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A clinical trial is a research study that tests new medical treatments, drugs, devices, or procedures to determine their safety and effectiveness. Trials are carefully designed and monitored to protect participants while advancing medical knowledge.
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Clinical trials follow strict safety guidelines and ethical standards. Trials must be reviewed and approved, and participants are closely monitored by medical professionals throughout the study. You can withdraw at any time if you choose.
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Will I receive a placebo instead of treatment?
When effective treatment exists, participants typically receive either the standard treatment plus the study intervention, or the standard treatment plus placebo. You would not be denied effective care. Placebos are primarily used when no proven treatment is available, or in addition to standard care. Your trial consent form will clearly explain what treatments you may receive.
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Data: ClinicalTrials.gov · synced Feb 10, 2026 · Source of record for eligibility and locations