Imaging the Respiratory Effects of Truncal Adiposity in Acute Hypoxemic Respiratory Failure
Maurizio F. Cereda, MD
Summary
Acute Hypoxemic Respiratory Failure (AHRF) is a condition in which injury to the lungs impairs the ability of the air sacs (alveoli) to ventilate and exchange oxygen. This impairment may be worsened in individuals with elevated body weight, particularly when fat tissue compresses the lungs and promotes alveolar collapse. The impact of body weight on lung function may be greater in individuals with upper-body fat distribution. Two common interventions for AHRF-positive end-expiratory pressure (PEEP) and prone positioning-are used to improve lung ventilation. However, it is unclear whether these therapies are equally effective across different body weight categories and fat distributions. This study will evaluate whether body weight and fat distribution affect patients' lung inflation responses to PEEP and prone positioning. Lung inflation will be assessed using electrical impedance tomography (EIT), a bedside imaging tool that maps lung ventilation, and esophageal manometry, which estimates lung compression through a thin catheter placed in the esophagus. Laboratory tests will also be used to measure markers of inflammation and AHRF severity and find correlations with fat distribution and responses to the tested treatments.. Patients with AHRF requiring mechanical ventilation will be enrolled across a range of body weights. Each participant will undergo combinations of two PEEP levels and two body positions (supine and prone) for 30 minutes each. At the end of the study procedures, clinical care will continue as determined by the treating team.
Description
This study investigates the relationship between body habitus and the physiological response to ventilatory interventions in patients with Acute Hypoxemic Respiratory Failure (AHRF). The primary objectives are to determine: 1. Whether excess body weight affects the regional lung inflation response to PEEP and prone positioning; 2. Whether body fat distribution (e.g., central vs. peripheral) is associated with lung recruitment; 3. Whether inflation responses correlate with laboratory markers of systemic inflammation and AHRF severity. Adult patients with AHRF requiring invasive mechanical ven…
Eligibility
- Age range
- 18–80 years
- Sex
- All
- Healthy volunteers
- No
Inclusion Criteria: * AHRF with PaO2/FiO2 \<= 300 mmHg) intubated for less than 72 hours * Presence of an arterial line for blood gas measurement and blood pressure monitoring * 18 years or older Exclusion Criteria: * Suspected pregnancy, pregnancy or less than six weeks postpartum * Younger than 18 years or older than 80 years. * Subject enrolled in another interventional research study * Presence of pneumothorax * Usage of any devices with electric current generation such as pacemaker or internal cardiac defibrillator * Preexisting chronic lung disease or pulmonary hypertension * Acute ca…
Interventions
- OtherPEEP Titration Using Electrical Impedance Tomography (EIT)
EIT will be used to guide individualized PEEP titration in mechanically ventilated patients with AHRF. Each subject will receive mechanical ventilation at two PEEP levels: PEEP\_CLIN (set by the treating clinician) PEEP\_TIT (identified using EIT to minimize alveolar collapse and overdistension) Both levels will be maintained for 30 minutes in each body position, with continuous physiologic data collected during each phase.
- ProcedureBody Positioning: Supine and Prone
Each subject will be ventilated in both the supine and prone positions. Positioning will follow institutional protocols and be coordinated with clinical staff to ensure safety. After supine assessments are completed, the patient will be transitioned to prone, followed by a recruitment maneuver to standardize lung volume history. The PEEP titration protocol will then be repeated in the prone position.
Location
- Massachusetts General HospitalBoston, Massachusetts