Healthy Subjects (HS)PHYSIOCLEARNCT07722377
Effect of Continuous Nebulisation of Isotonic Saline Solution Combined With Heated Humidification on Mucociliary Clearance in Healthy Subjects
A study testing Heated humidification and Saline Nebulization in people with Healthy Subjects (HS), run by Cliniques universitaires Saint-Luc- Université Catholique de Louvain at 1 site in Belgium.
Trial summary
Mucociliary clearance is an essential defense mechanism of the lungs that helps remove inhaled particles, pathogens, and airway secretions. This process depends on the coordinated action of cilia, mucus properties, and airway hydration. Read more about this study
- Who is it for?
- Ages 18 years and olderHealthy volunteers can take part
- Conditions the study is for
- Healthy Subjects (HS)
- What is being tested?
- Heated humidification and Saline Nebulization
- Type of treatment
- Medical device
- Could I receive a placebo?
- No, everyone receives an active treatment
- How many people
- 10 participants
- Where
- 1 siteBelgium
- Study dates
- Oct 2026to Dec 2026
- Phase
- Interventional
Key requirements
Who can take part, as listed by the sponsor. Only the study team can confirm whether you are eligible, so take this list to your doctor.
- Ages 18 years and older
- All sexes
- Healthy volunteers accepted
- Adult, Older adult
Who may be able to join
- >18 years old
- healthy spiromètry
Who cannot join
- <18 years old
- Pathologic spiromètry
- Active smokers
Trial locations and contacts
1 site in 1 country. Contact the study team or a site near you to ask about taking part.
Belgium1 site
Cliniques universitaires Saint-Luc
Brussels, 1200
Christophe Thibon, +32 764 16 23, christophe.thibon@saintluc.uclouvain.be
About this study
Mucociliary clearance is an essential defense mechanism of the lungs that helps remove inhaled particles, pathogens, and airway secretions. This process depends on the coordinated action of cilia, mucus properties, and airway hydration. In healthy individuals, mucus is continuously transported toward the throat, allowing effective clearance of harmful substances. However, this mechanism can be influenced by the hydration status of the airway surface liquid.
Heated humidification delivered through high-flow nasal cannula (HFNC) has been shown to improve airway hydration, enhance ciliary function, and support mucociliary clearance. In addition, nebulized saline solutions are commonly used to modify mucus properties. Hypertonic saline has demonstrated short-term benefits in improving mucus hydration and clearance, but its use may be associated with side effects such as airway irritation or bronchoconstriction. In contrast, the effects of isotonic saline remain unclear, particularly when delivered in large volumes.
Read more
The rationale of this study is that continuous nebulization of isotonic saline, when combined with heated humidification, may provide a sufficient cumulative amount of sodium to improve airway hydration and mucociliary clearance, potentially mimicking the effects of hypertonic saline without its adverse effects.
This study is a randomized controlled cross-over trial conducted in healthy adult volunteers. Each participant will undergo three experimental sessions: a baseline assessment without intervention, a control condition with heated humidification alone, and an intervention condition combining heated humidification with continuous isotonic saline nebulization. The order of the control and intervention sessions will be randomized.
Mucociliary clearance will be assessed using pulmonary scintigraphy. Participants will inhale radiolabeled aerosol particles (99mTc-DTPA), and the clearance of these particles from the lungs will be monitored over time using a gamma camera. Images will be acquired at regular intervals to quantify the rate of particle retention and clearance under each condition.
The primary objective of the study is to determine whether continuous isotonic saline nebulization combined with heated humidification improves mucociliary clearance compared to heated humidification alone.
Secondary outcomes include the evolution of mucociliary clearance over time during and after the intervention, as well as participant comfort assessed using a Likert scale.
The findings of this study may help improve understanding of airway hydration strategies and contribute to optimizing respiratory care techniques aimed at enhancing mucus clearance.
- Conditions
- Healthy Subjects (HS)
- Being tested
- Heated humidification, Saline Nebulization
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
Heated humidificationDevice
gas heated humidification through HFNC
Saline NebulizationDevice
0.9 % Saline continuous nebulization
| Study group | Role | What they receive |
|---|---|---|
| Baseline | No intervention | Not described |
| Humidification | Active comparator | Not described Receives: Device: Heated humidification |
| Humidification + nebulization | Experimental | Not described Receives: Device: Heated humidification; Device: Saline Nebulization |
What is being measured
The primary outcome is the main question the study is designed to answer.
Mucociliary clearance
Mucociliary clearance will be assessed using biplane scintigraphy
Measured: 20 minutes interval from the onset through study completion 2 hours
Secondary outcomes (1)
Overall Confort during the use of the device
The comfort while using the device will be assessed using a Lickert Scale
Measured: At study completion 2 hours
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted23 Jul 2026
- Study startOct 2026 (estimated)
- Primary completionOct 2026 (estimated)
- Study completionDec 2026 (estimated)
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Other trials for Healthy Subjects (HS)Studies of the same condition, open and under way.
- What the trial phases meanHow a treatment moves from first tests in people to approval.
More details
For doctors and researchers: how the study is designed, who runs it, and its registry IDs.
Study design
- Study type
- Interventional
- Phase
- Phase N/A
- Primary purpose
- Treatment
- Allocation
- Randomised
- Intervention model
- Crossover
- Masking
- None (open label)
- Enrolment
- 10 participants (estimated)
Sponsor and investigators
- Lead sponsor
- Cliniques universitaires Saint-Luc- Université Catholique de Louvain
- Sponsor type
- University, hospital or other
- Collaborators
- Fisher and Paykel Healthcare, Aerogen
- Responsible party
- Sponsor
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT07722377
- Sponsor's protocol ID
- 2026/09FEV/074
- Acronym
- PHYSIOCLEAR
- Status last verified
- May 2026
- First submitted
- 24 Apr 2026
- Last updated
- 23 Jul 2026
- Results posted
- No
- Data monitoring committee
- No
- FDA-regulated drug
- No
- FDA-regulated device
- No
- Individual data sharing
- No