EPVent 2- A Phase II Study of Mechanical Ventilation Directed by Transpulmonary Pressures


About this study

This phase II multi-centered, randomized controlled trial of mechanical ventilation directed by esophageal pressure measurement will test the primary hypothesis that using a strategy of maintaining a minimal but positive transpulmonary pressure (PTP = airway pressure minus pleural pressure) throughout the ventilatory cycle will lead to an improvement in patient survival.

Participation eligibility

Participant eligibility includes age, gender, type and stage of disease, and previous treatments or health concerns. Guidelines differ from study to study, and identify who can or cannot participate. There is no guarantee that every individual who qualifies and wants to participate in a trial will be enrolled. Contact the study team to discuss study eligibility and potential participation.

Inclusion Criteria:

  • Acute onset of ARDS as defined by the Berlin Consensus Conference definitions:
    1. Hypoxemic respiratory failure with PaO2 / FIO2 ratio < 200 mmHg
    2. b) Bilateral alveolar/interstitial infiltrates on chest x-ray, with opacities not present for more than 7 days
    3. Respiratory failure not fully explained by cardiac failure or fluid overload
    4. Intubation on controlled ventilation and receiving PEEP ≥ 5 cm H2O
  • Age 16 years or older
  • Duration of ARDS 36 hours or less from meeting final Berlin criterion.

Exclusion Criteria:

  • Received mechanical ventilation more than 96 hours
  • Recently treated or bleeding varices, esophageal stricture, hematemesis, esophageal trauma, recent esophageal surgery or other contraindication for nasogastric tube placement
  • Severe coagulopathy (platelet count < 5000/microliter or INR > 3)
  • History of lung or liver transplantation
  • Elevated intracranial pressure or conditions where hypercapnia-induced elevations in intracranial pressure should be avoided
  • Evidence of active air leak from the lung
  • not committed to full support
  • Participation in other intervention trials for ARDS or for sepsis within the past 30 days.
  • Neuromuscular disease that impairs ability to ventilate spontaneously
  • Severe chronic liver disease, defined as Child-Pugh Score of ≥12
  • Treating clinician refusal, or unwillingness to commit to controlled ventilation for at least 24 hours
  • Inability to get informed consent from the patient or surrogate.
  • Use of rescue therapies for prior to enrollment (e.g. nitric oxide, ECMO, prone positioning, high frequency oscillation). This does not exclude cases where these therapies were used as the initial mode of ventilation

Participating Mayo Clinic locations

Study statuses change often. Please contact the study team for the most up-to-date information regarding possible participation.

Mayo Clinic Location Status

Rochester, Minn.

Mayo Clinic principal investigator

Richard Oeckler, M.D., Ph.D.

Closed for enrollment

More information


  • Optimal ventilator management for patients with acute respiratory distress syndrome (ARDS) remains uncertain. Lower tidal volume ventilation appears to be beneficial, but optimal management of positive end-expiratory pressure (PEEP) remains unclear. The Esophageal Pressure-Guided Ventilation 2 Trial (EPVent2) aims to examine the impact of mechanical ventilation directed at maintaining a positive transpulmonary pressure (PTP) in patients with moderate-to-severe ARDS. Read More on PubMed
  • Trials comparing higher vs lower levels of positive end-expiratory pressure (PEEP) in adults with acute lung injury or acute respiratory distress syndrome (ARDS) have been underpowered to detect small but potentially important effects on mortality or to explore subgroup differences. Read More on PubMed
  • Acute respiratory distress syndrome (ARDS) and ventilator induced lung injury (VILI) continue to challenge clinicians who care for the critically ill. Current research in ARDS has focused on ventilator strategies to improve the outcome for these patients. In this review, we emphasize the limitations of managing ventilators based on airway pressures alone. Specifically, basic pulmonary mechanics including chest wall compliance and transpulmonary pressure are reviewed. This review suggests that perturbations in chest wall compliance and transpulmonary pressure may explain the lack of efficacy observed in recent clinical trials of ventilator management. We present a method for estimating pleural and transpulmonary pressures from esophageal manometry. Quantifying these variables and individualizing ventilator management based on individual patient physiology may be useful to intensive care clinicians who treat patients with ARDS. Read More on PubMed
  • Survival of patients with acute lung injury or the acute respiratory distress syndrome (ARDS) has been improved by ventilation with small tidal volumes and the use of positive end-expiratory pressure (PEEP); however, the optimal level of PEEP has been difficult to determine. In this pilot study, we estimated transpulmonary pressure with the use of esophageal balloon catheters. We reasoned that the use of pleural-pressure measurements, despite the technical limitations to the accuracy of such measurements, would enable us to find a PEEP value that could maintain oxygenation while preventing lung injury due to repeated alveolar collapse or overdistention. Read More on PubMed
  • Low-tidal-volume ventilation reduces mortality in critically ill patients with acute lung injury and acute respiratory distress syndrome. Instituting additional strategies to open collapsed lung tissue may further reduce mortality. Read More on PubMed
  • Pressure inflating the lung during mechanical ventilation is the difference between pressure applied at the airway opening (Pao) and pleural pressure (Ppl). Depending on the chest wall's contribution to respiratory mechanics, a given positive end-expiratory and/or end-inspiratory plateau pressure may be appropriate for one patient but inadequate or potentially injurious for another. Thus, failure to account for chest wall mechanics may affect results in clinical trials of mechanical ventilation strategies in acute respiratory distress syndrome. By measuring esophageal pressure (Pes), we sought to characterize influence of the chest wall on Ppl and transpulmonary pressure (PL) in patients with acute respiratory failure. Read More on PubMed
  • Acute lung injury is a critical illness syndrome consisting of acute hypoxemic respiratory failure with bilateral pulmonary infiltrates that are not attributed to left atrial hypertension. Despite recent advances in our understanding of the mechanism and treatment of acute lung injury, its incidence and outcomes in the United States have been unclear. Read More on PubMed
  • The purpose of this paper is to review the mechanisms of ventilator-induced lung injury as a basis for providing the less damaging mechanical ventilation in patients with acute respiratory failure. Read More on PubMed
  • Most patients requiring mechanical ventilation for acute lung injury and the acute respiratory distress syndrome (ARDS) receive positive end-expiratory pressure (PEEP) of 5 to 12 cm of water. Higher PEEP levels may improve oxygenation and reduce ventilator-induced lung injury but may also cause circulatory depression and lung injury from overdistention. We conducted this trial to compare the effects of higher and lower PEEP levels on clinical outcomes in these patients. Read More on PubMed
  • As more patients survive the acute respiratory distress syndrome, an understanding of the long-term outcomes of this condition is needed. Read More on PubMed

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