Positive End-expiratory Pressure and Esophageal Catheter Optimal Calibration Volume in ARDS Patients

Positive End-expiratory Pressure and Esophageal Catheter Optimal Calibration Volume in ARDS Patients

The use of esophageal balloon catheter to estimate pleural pressure has gained renewed popularity in recent years. Indeed, measurement of transpulmonary pressure may allow a more pathophysiological-based approach to ventilator strategy in acute respiratory distress syndrome (ARDS) patients. Nevertheless, it is well known that esophageal balloon catheter derived parameters can be influenced by several patient-related or technical-related factors.

During a PEEP trial, the investigators will observe in-vivo the esophageal pressure and derived measurements obtained using different esophageal balloon calibration volumes.

Inclusion Criteria:

• Diagnosis of ARDS with a PEEP of at least 8 cmH2O
• Fraction of inspired oxygen not higher than 80%
• Intubated and ventilated in Volume Control Ventilation mode set by the attending physician according to clinical criteria
• Need of continuous sedation through intravenous anesthetics and full neuromuscular blockade

Exclusion Criteria:

• Been pregnant or breastfeeding
• Hemodynamic instability
• Presence of tracheobronchial fistula
• Known pneumothorax
• Leak in airway circuitry
• Presence of any kind of inhalator therapy (e.g. Heliox, nitric oxide, anesthetic conserving device)
• Recent history of nasal trauma or lesion of nasal cavity
• Recent history of esophageal, gastrointestinal, ENT, thoracic or cardiac surgery (less than 2 months)
• Known or suspected esophageal varices
• Congenital, acquired or drug-induced hemostatic disorder
• Thrombocytopenia (less than 50000/mm3)
• Recent history of Traumatic Brain Injury or thoraco-abdominal trauma (less than 1 months)
• Rib or sternal fractures