for people ages 18 years and up (full criteria)
Healthy Volunteers
healthy people welcome
at La Jolla, California
study started
completion around
Principal Investigator
by Alex Pearce



Respiratory physiology involves a complex interplay of elements including control of breathing, respiratory drive, pulmonary mechanics, distribution of ventilation and gas exchange. Body position may also play an important role in respiratory mechanics. While effective methods exist for measuring these variables, they are typically measured in isolation rather than in combination. In pulmonary disease, decreasing mechanical stress and strain and optimizing transpulmonary pressure or the distending pressure across the lung, minimizing overdistention and collapse are central to clinical management. Obesity has a significant impact on pulmonary mechanics and is a risk factor for obstructive sleep apnea (OSA). However, our understanding of these elements is limited even in the general population. The investigators plan to use various validated methods to assess control of breathing, respiratory drive, distribution of ventilation and gas exchange to obtain a better understanding of underlying physiologic signatures in patients with and without obesity and the role of posture/position, with a secondary analysis comparing participants with and without obstructive sleep apnea.


Pulmonary Disease, Respiratory System Abnormalities, OSA, Respiratory Failure, Respiratory Insufficiency, Position change, BMI>24.9 kg/m2, BMI 18-24.9 kg/m2


You can join if…

Open to people ages 18 years and up

  • 18 years or older
  • Non-smokers

You CAN'T join if...

  • <18 years old
  • Significant history of pulmonary disease
  • Chest wall, anatomical, physical abnormalities, skin integrity issues precluding placement of electrode belt in direct contact with skin
  • Skin integrity issues precluding placement of nose clips, or transcutaneous carbon dioxide monitoring
  • Inability to form a seal around a mouthpiece
  • Known esophageal strictures, webs, or varices (if esophageal manometry to be included)
  • Known platelet count < 100,000 (if esophageal manometry to be included)
  • On therapeutic anticoagulation (if esophageal manometry to be included)
  • Known multidrug resistant (MDR) pulmonary infection
  • Non-English language speakers
  • Chronic hypoxemic respiratory failure
  • Confirmed or suspected intracranial bleed, stroke, edema
  • Active implants (i.e. implantable electronic devices such as pacemakers, cardioverter defibrillators or neurostimulators) or if device compatibility is in doubt
  • Pregnant or lactating patients as safety and efficacy for use of EIT in such cases has not been verified


  • University of California San Diego Health
    La Jolla California 92037 United States

Lead Scientist at UCSD

  • Alex Pearce
    Associate Physician Diplomate, Medicine, Vc-health Sciences-schools. Authored (or co-authored) 16 research publications


accepting new patients by invitation only
Start Date
Completion Date
University of California, San Diego
Study Type
Expecting 40 study participants
Last Updated