The goal of this interventional crossover study in morbidly obese intubated and mechanically
ventilated patients is to describe the respiratory mechanics and the heart-lung interaction
at titrated positive end-expiratory pressure levels following a recruitment maneuver with
transthoracic echocardiography and electric impedance tomography imaging.
Obese patients under mechanical ventilation are more likely to develop atelectasis as a
consequence of the increased abdominal weight. Atelectasis is the primary responsible for
respiratory insufficiency and impossibility to wean obese patients from respiratory support.
In a previous study we demonstrated the efficacy of the application of titrated PEEP levels
following a recruitment maneuver in obese patients, i.e. improvement in respiratory mechanics
and gas exchanges without negative hemodynamic effects.
The application of lung and heat imaging will allow us to quantitatively describe:
- Increase in aerated lung tissue (reduction of atelectasis)
- Reduction of over-inflation of the ventilated regions
- Recoupling of ventilation and perfusion
- Improvement in right heart function by reduction of right heart afterload
- ICU admitted requiring intubation and mechanical ventilation
- BMI ≥ 35 kg/m2
- Waist circumference > 88 cm (for women)
- Waist circumference > 102 cm (for men)
- Known presence of esophageal varices
- Recent esophageal trauma or surgery
- Severe thrombocytopenia (Platelets count ≤ 5,000/mm3)
- Severe coagulopathy (INR ≥ 4)
- Presence or history of pneumothorax
- Patients with poor oxygenation index at screening (PaO2/FiO2< 100 mmHg with at least
10 cmH2O of PEEP)
- Pacemaker and/or internal cardiac defibrillator
- Hemodynamic parameters: systolic blood pressure (SBP) <100 mmHg and >180 mmHg, or if
SBP is between 100-180 mmHg on high dose of IV continuous infusion norepinephrine (>20
μg per minute), or dobutamine (>10 μg per minute), or dopamine (>10 μg per Kg per
minute), or epinephrine (>10 μg per minute).