Physiological Flow of Liquids in Healthy Swallowing
Study Details
Study Description
Brief Summary
Thickened liquids are commonly used as an intervention for people with dysphagia (swallowing impairment). However, the field currently lacks a proper understanding of how this intervention works. The overall goal of the project is to collect measurements of bolus flow through the oropharynx (i.e., mouth and throat) during swallowing. The factors that are expected to influence bolus flow include the liquid/food consistency (i.e., thin, slightly-thick, mildly-thick, moderately-thick, extremely thick, solid) and the forces applied during swallowing (i.e., tongue pressures and swallowing muscle contraction). The objective is to determine how these factors interact to influence the flow of a bolus through the oropharynx in healthy swallowing.
| Condition or Disease | Intervention/Treatment | Phase |
|---|---|---|
|
N/A |
Detailed Description
The aims of this study are as follows:
Aim 1: To determine the relationship between bolus flow and healthy swallowing physiology. The investigators will collect concurrent videofluoroscopic and physiological measures of swallowing (tongue pressure, electromyography [sEMG]) in healthy adults using barium stimuli across the continuum of liquid consistency (thin, slightly thick, mildly thick, moderately thick and extremely thick liquids, as defined by the International Dysphagia Diet Standardisation Initiative, www.iddsi.org). Significance: This will show the impact of consistency on bolus flow through the oropharynx, controlling for the forces used to initiate flow and propel the bolus.
Aim 2: To compare healthy swallowing physiology for barium versus non-barium stimuli. The investigators will collect physiological measures of swallowing using barium and non-barium stimuli matched for consistency. Significance: This will determine how swallowing behaviors (tongue pressures, sEMG) differ between barium and non-barium stimuli with matched consistency, enabling us to develop models of flow accounting for these differences.
Aim 3: To compare healthy swallowing physiology across different commercial barium products. Significance: This will determine whether differences in barium concentration or brand influence swallowing behaviors, enabling us to make recommendations regarding ideal contrast agents for use in radiographic swallowing assessment.
Aim 4: To explore swallowing behaviors across solid foods of different consistencies (minced and moist, soft & bite-sized, regular) in comparison to liquids. Significance: This will provide preliminary data regarding swallowing physiology across these consistencies.
Study Design
Arms and Interventions
| Arm | Intervention/Treatment |
|---|---|
| Experimental: Healthy Adults Participants will be asked to swallow a series of up to 54 liquid stimuli: a) liquid barium (different brands and concentrations); b) a 20% w/v concentration liquid barium thickened to different consistencies using either a starch-based or xanthan-gum based food thickener; c) lemon-flavored water thickened to different consistencies using either a starch-based or xanthan-gum based food thickener; and/or d) foods representative of "minced and moist", "soft-and-bite-sized" or "regular" consistency. |
Other: Starch-thickened liquids
Thickener added in amounts required to reach slightly thick, mildly thick, moderately thick and extremely thick consistencies, as defined by the International Dysphagia Diet Standardisation Initiative flow test.
Other Names:
Other: Xanthan-gum thickened liquids
Thickener added in amounts required to reach slightly thick, mildly thick, moderately thick and extremely thick consistencies, as defined by the International Dysphagia Diet Standardisation Initiative flow test.
Other Names:
Combination Product: Barium concentration
Commercially available barium products diluted to different concentrations (i.e., 20% w/v, 40% w/v) through the addition of water
Other Names:
Other: Food consistency
Commercially available food products in different consistencies: Carr's Table Water crackers, Squish gummy candies, baby carrots
|
Outcome Measures
Primary Outcome Measures
- Penetration-Aspiration Scale (Swallow Safety) [Baseline (single timepoint only)]
The Penetration-Aspiration Scale is an 8-point categorical scale that will be used to characterize swallowing safety for each bolus based on the depth to which any material enters the airway and whether or not the material is ejected. Levels 1 and 2 on the scale are considered safe, while levels > 3 are considered unsafe. Actual scale scores (1-8) will be recorded and then converted to binary categorical scores (< 3 vs >/= 3).
- Swallowing Efficiency [Baseline (single timepoint only)]
Pixel-based measures of post-swallow residue in the pharynx will be performed on the videofluoroscopy recordings.
- Number of swallows per bolus [Baseline (single timepoint only)]
The number of swallows needed to clear a single bolus will be counted. 1-2 swallows is considered efficient, while > 2 for a single bolus is considered inefficient.
- Swallow Reaction Time [Baseline (single timepoint only)]
The time interval between the bolus passing the ramus of the mandible (jaw) and onset of the hyoid burst movement in swallowing will be calculated (in milliseconds) for each bolus.
- Hyoid burst to Upper Esophageal Sphincter Opening Interval [Baseline (single timepoint only)]
The time interval between onset of the hyoid burst and opening of the upper esophageal sphincter will be measured (in milliseconds) for each bolus.
- Upper Esophageal Sphincter Opening Duration [Baseline (single timepoint only)]
The time interval between opening and closing of the upper esophageal sphincter will be measured for each bolus (in milliseconds).
- Time-to-Laryngeal-Vestibule-Closure [Baseline (single timepoint only)]
The time interval between onset of the hyoid burst and achieving closure of the laryngeal vestibule will be measured for each bolus (in milliseconds)
- Laryngeal Vestibule Closure Duration [Baseline (single timepoint only)]
The time interval between laryngeal vestibule closure onset and offset will be measured for each bolus (in milliseconds)
- Maximum Pharyngeal Constriction [Baseline (single timepoint only)]
The degree of pharyngeal constriction will be measured using pixel-based tracing in ImageJ software on the frame of maximum constriction.
- Pharyngeal Area at Rest [Baseline (single timepoint only)]
The size of the pharynx will be measured at rest using pixel-based tracing in ImageJ software.
- Upper Esophageal Sphincter Opening diameter [Baseline (single timepoint only)]
The diameter of upper esophageal sphincter opening on the frame of maximum distension will be measured using pixel-based tracing in Image J software.
- Tongue-Palate Pressure [Baseline (single timepoint only)]
The amplitude of tongue-palate pressure will be measured continuously throughout swallowing using the KayPentax Digital Swallow Workstation Swallowing Signals Lab 3-bulb tongue pressure array.
- Submental Surface Electromyography [Baseline (single timepoint only)]
The amplitude of submental suprahyoid muscle electromyographic (EMG) activity will be measured continuously using the surface EMG module of the KayPentax Digital Swallow Workstation Swallowing Signals Lab.
- Direction of Airflow [Baseline (single timepoint only)]
The direction of breathing (inspiration/expiration) will be measured continuously via nasal cannula using the airflow module of the KayPentax Digital Swallow Workstation Swallowing Signals Lab. This information will be used to identify the direction of airflow immediately preceding and immediately following each swallow. An expiration-swallow-expiration pattern is considered normal. All other variants (inspiration-swallow-expiration, inspiration-swallow-inspiration, expiration-swallow-inspiration) are considered abnormal.
- Duration of Respiratory Pause [Baseline (single timepoint only)]
The duration of the pause in respiration (in milliseconds) seen with each swallow will be measured from the continuous airflow waveform collected via nasal cannula using the airflow module of the KayPentax Digital Swallow Workstation Swallowing Signals Lab.
- Number of chews per bolus [Baseline (single timepoint only)]
The number of chews taken for each bolus of food will be counted
- Bolus consistency when ready to swallow [Baseline (single timepoint only)]
Some of the solid food boluses will be expectorated when the participant indicates they have finished chewing and are ready to swallow. Particle size will be measured to determine consistency.
Eligibility Criteria
Criteria
Inclusion Criteria:
- healthy adults
Exclusion Criteria:
-
prior history of swallowing, motor speech, gastro-esophageal or neurological difficulties, chronic sinusitis or taste disturbance
-
history of surgery to the speech or swallowing apparatus (other than routine tonsillectomy or adenoidectomy)
-
Type 1 Diabetes
-
cognitive communication difficulties that may hinder comprehension of the study documents
-
known allergies to latex, food coloring or dental glue
-
current pregnancy
-
recent x-ray to the neck (in the past 6 months)
-
occupationally exposure to radiation exceeding 10 milliSieverts in the year
Contacts and Locations
Locations
| Site | City | State | Country | Postal Code | |
|---|---|---|---|---|---|
| 1 | Toronto Rehabilitation Institute | Toronto | Ontario | Canada | M5G 2A2 |
Sponsors and Collaborators
- University Health Network, Toronto
- National Institute on Deafness and Other Communication Disorders (NIDCD)
Investigators
- Principal Investigator: Catriona Steele, PhD, KITE - Toronto Rehabilitation Institute, University Health Network
Study Documents (Full-Text)
None provided.More Information
Publications
None provided.- CAPCR 15-9431 (NIH_HV)
- 5R01DC011020
- CAPCR 15-9431