Clinical trial NCT07019831: A Study of Body Fat Distribution and Airway Mechanics in Healthy Adults
Official title: Imaging the Respiratory Effects of Truncal Adiposity in Healthy Subjects
Study type: INTERVENTIONAL
Overall status: NOT_YET_RECRUITING
Phase: NA
Conditions: Healthy Volunteers Only
Keywords: obesity
electrical impedance tomography
computed tomography
esophageal manometry
airway geometry
Lead sponsor: Massachusetts General Hospital
Sponsor class: OTHER
Collaborators: name: National Institutes of Health (NIH)
First posted: 2025-06-13
Enrollment: 20
Sex: ALL
Minimum age (years): 18
Maximum age (years): 80
Standard ages: ADULT
OLDER_ADULT
Accepts healthy volunteers: yes
Allocation: NA
Intervention model: SINGLE_GROUP
Intervention model description: In a prospective, single-center, physiological, crossover study, the investigators will recruit 20 healthy volunteers across four standard body mass index categories (normal weight, overweight, class I obesity, class II/III obesity).
Primary purpose: DIAGNOSTIC

Brief summary: This study investigates how body fat distribution affects airway closure and lung mechanics in healthy adults. Using Electrical Impedance Tomography (EIT), esophageal manometry, and computed tomography (CT), we aim to characterize how varying BMI and fat topography influence regional ventilation and airway collapse in supine and prone positions. Healthy volunteers with a range of BMIs will undergo a 2-hour imaging session with noninvasive and minimally invasive monitoring.

Detailed description: This physiological research study explores the relationship between body habitus, fat distribution, and mechanical responses of the lung to the prone and supine position. In a prospective, single-center, physiological, crossover study, study subjects (n=20) will be recruited among healthy volunteers across BMI categories. Lung function will be assessed in the supine and prone position (maintained for 15 min). Intrathoracic pressure (ITP) will be measured using esophageal manometry. Airway opening pressure (AOP) will be measured by as the airway pressure (non-invasively applied through a mask) needed to match ITP. Regional ventilation will be measured in both positions using electrical impedance tomography. Subjects will then transfer to the computed tomography (CT) scanner, where supine and prone images will be acquired during breath holds after normal expiration and after full inspiration. CT scans will then be analyzed for the quantification of lung volumes, thoracic adipose mass and airway geometry.

Eligibility criteria: Inclusion Criteria

• Healthy subjects older than 18 years and younger than 80.

Exclusion Criteria

* Pre-existing cardiopulmonary disease
* history of tobacco or ecigarette smoking

Primary outcomes:
measure: Lung volumes
timeFrame: Day 1, 15 minutes after breathing in the supine and in the prone position
Secondary outcomes:
measure: Thoracic adiposity
timeFrame: Day 1
Other outcomes:
measure: Airway diameters
timeFrame: Day 1, after 15 minutes in the supine and prone positions
measure: Intrathoracic pressure (ITP)
timeFrame: Day 1, after 15 minutes in the supine and prone positions.
measure: Airway opening pressure (AOP)
timeFrame: Day 1, after 15 minutes in supine and prone position
measure: Regional ventilation
timeFrame: Day 1, after 15 minutes in the supine or prone position
measure: Age
timeFrame: Day 1
measure: Height
timeFrame: Day 1
measure: Weight
timeFrame: Day 1
measure: Thoracic circumference
timeFrame: Day 1
measure: Abdominal circumference
timeFrame: Day 1
measure: Hip circumference
timeFrame: Day 1
measure: Medical history
timeFrame: Day 1
Locations:
Study officials:
References:
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citation: Florio G, De Santis Santiago RR, Fumagalli J, Imber DA, Marrazzo F, Sonny A, Bagchi A, Fitch AK, Anekwe CV, Amato MBP, Arora P, Kacmarek RM, Berra L. Pleural Pressure Targeted Positive Airway Pressure Improves Cardiopulmonary Function in Spontaneously Breathing Patients With Obesity. Chest. 2021 Jun;159(6):2373-2383. doi: 10.1016/j.chest.2021.01.055. Epub 2021 May 8.