Skip to content

Respiratory Kinematics During Voluntary and Reflex Cough in Healthy Adults

Respiratory Kinematics During Voluntary and Reflex Cough in Healthy Adults

Status
Completed
Phases
Phase 1Phase 2
Study type
Interventional
Source
ClinicalTrials.gov
Registry ID
NCT01854268
Enrollment
25
Registered
2013-05-15
Start date
2013-05-31
Completion date
2014-05-31
Last updated
2022-02-09

For informational purposes only — not medical advice. Sourced from public registries and may not reflect the latest updates. Terms

Conditions

Cough

Keywords

cough

Brief summary

Cough is a defensive behavior that involves three stages. A large inspiratory phase, a compression phase where the vocal folds close and subglottal pressure is developed, and an expiratory phase. Cough serves to protect the upper and lower airways from material such as liquids, solids, or saliva, that have been aspirated. There are two types of cough: voluntary and reflex cough. Voluntary cough involves a cough to command. Reflex cough is a cough that is generated secondary to a stimulus in or near the airway. There has been some research regarding the differences between voluntary and reflex cough. However, no research has described the differences in airflow or movement pattern (kinematics) between the two types of cough. This study seeks to determine the respiratory kinematics and airflow differences between voluntary and reflex cough in healthy participants.

Detailed description

As a participant, completion of this study will require the following: Investigators will first place cotton elastic bands around your chest and abdomen so that measures of chest wall and abdominal movements can be measured. Then, tests of your breathing made from pulmonary function testing will be completed. Investigators will then have you complete a maximum inspiration followed by a maximum expiration three times. Investigators will ask you to produce a voluntary cough three times into a facemask which is attached to a computer. Then the investigators will provide you with nebulized water (FOG) through the facemask for up to a minute three times. You will have a minute break in between each presentation. Finally, the investigators will provide you with a nebulized dose of Capsaicin, which is derived from hot peppers, through the same facemask used in all of the above tasks. You will receive three doses of capsaicin and be provided with water at any time during the study.

Interventions

DRUGHealthy adults who receive capsaicin

Participants will be seated in a comfortable chair and fitted with cotton elastic bands designed to measure changes in chest wall and abdominal movement during cough. The participant will hold a facemask attached to a pneumotachograph, nebulized, and dosimeter. The participant will receive 3 nebulized doses of 200 microMolar capsaicin through the facemask. The participants will have a minute in between each presentation and water will be available at all times.

Sponsors

University of Florida
Lead SponsorOTHER

Study design

Allocation
NA
Intervention model
SINGLE_GROUP
Primary purpose
DIAGNOSTIC
Masking
NONE

Eligibility

Sex/Gender
ALL
Age
18 Years to 80 Years
Healthy volunteers
Yes

Inclusion criteria

* Healthy adults between the ages of 18-80 years. * Ability to provide informed consent.

Exclusion criteria

* No history of smoking within the last 5 years as this reduces the sensitivity to capsaicin * No history of neurological disease (i.e. Parkinson's disease, stroke, traumatic brain injury, etc.) * No known allergy to capsaicin * No history of respiratory disease (i.e. asthma, chronic obstructive pulmonary disease, or respiratory infection within the last 5 weeks.)

Design outcomes

Primary

MeasureTime frameDescription
Lung Volume Initiation1 hourRespiratory kinematic measure: lung volume initiation (LVI) Lung volume initiation is a measure of the volume of air in the lungs prior to a respiratory task.

Secondary

MeasureTime frameDescription
Peak Expiratory Airflow Rate1 hourAirflow measures: Peak expiratory airflow rate Peak expiratory flow rate is a measure of the velocity of air expelled from the respiratory apparatus during cough. Measured in liters/second.
Urge-to-cough1 hourUrge-to-cough: A measure of respiratory sensation that rates the perceived magnitude of the need to cough on a Borg scale (0=no urge-to-cough; 10=maximal urge-to-cough).

Countries

United States

Participant flow

Participants by arm

ArmCount
Healthy Adults Who Receive Capsaicin
Single treatment consisting of healthy adults. Healthy adults who receive capsaicin: Participants were seated in a comfortable chair and fitted with cotton elastic bands designed to measure changes in chest wall and abdominal movement during cough. The participant breathed through a facemask attached to a pneumotachograph, nebulizer, and dosimeter. The participant received 3 nebulized doses of 200 microMolar capsaicin through the facemask. The participants had a minute in between each presentation and water was available at all times. Pulmonary function testing: Investigators will first place cotton elastic bands around your chest and abdomen so that measures of chest wall and abdominal movements can be measured. Forced vital capacity and rest breathing maneuvers were completed. Nebulized water (Fog): The investigators will provide you with nebulized water (FOG) through the facemask for up to a minute three times. A minute break in between each presentation.
25
Total25

Baseline characteristics

CharacteristicHealthy Adults Who Receive Capsaicin
Age, Categorical
<=18 years
0 Participants
Age, Categorical
>=65 years
0 Participants
Age, Categorical
Between 18 and 65 years
25 Participants
Age, Continuous23.3 years
STANDARD_DEVIATION 3.3
Lung volume initiation23.3 %vital capacity, relative to EEL
STANDARD_DEVIATION 5.8
Peak expiratory airflow rate6.058 Liters/second
STANDARD_DEVIATION 0.56
Region of Enrollment
United States
25 participants
Sex: Female, Male
Female
14 Participants
Sex: Female, Male
Male
11 Participants
Urge-to-cough7 units on a scale
STANDARD_DEVIATION 0.32

Adverse events

Event typeEG000
affected / at risk
deaths
Total, all-cause mortality
— / —
other
Total, other adverse events
0 / 25
serious
Total, serious adverse events
0 / 25

Outcome results

Primary

Lung Volume Initiation

Respiratory kinematic measure: lung volume initiation (LVI) Lung volume initiation is a measure of the volume of air in the lungs prior to a respiratory task.

Time frame: 1 hour

Population: 25 healthy young volunteers participated in this study. The average age was 23 years and none had a history of respiratory or neurological disease.

ArmMeasureValue (MEAN)Dispersion
Healthy Adults Who Receive CapsaicinLung Volume Initiation23.3 % Vital Capacity, relative to EELStandard Deviation 5.7
Secondary

Peak Expiratory Airflow Rate

Airflow measures: Peak expiratory airflow rate Peak expiratory flow rate is a measure of the velocity of air expelled from the respiratory apparatus during cough. Measured in liters/second.

Time frame: 1 hour

ArmMeasureGroupValue (MEAN)Dispersion
Healthy Adults Who Receive CapsaicinPeak Expiratory Airflow RatePEFR - Voluntary Cough6.058 Liters/secondStandard Deviation 0.56
Healthy Adults Who Receive CapsaicinPeak Expiratory Airflow RatePEFR - Reflex Cough5.437 Liters/secondStandard Deviation 0.43
Secondary

Urge-to-cough

Urge-to-cough: A measure of respiratory sensation that rates the perceived magnitude of the need to cough on a Borg scale (0=no urge-to-cough; 10=maximal urge-to-cough).

Time frame: 1 hour

ArmMeasureValue (MEDIAN)Dispersion
Healthy Adults Who Receive CapsaicinUrge-to-cough6 units on a scaleStandard Error 0.4

Source: ClinicalTrials.gov · Data processed: Feb 4, 2026