NCT04524091

Prediction of Inspiratory Effort Response to High PEEP in Patients Recovering From ARDS

• Status: Recruiting
• Phase: —
• Study type: Observational
• Enrollment: 30 (estimated)
• Sponsor: Sanatorio Anchorena San Martin · Academic / Other
• Sex: All
• Age: 18 Years
• Healthy volunteers: Not accepted

Summary

Spontaneous breathing during the transition from controlled to assisted ventilation in ARDS may be harmful, as high respiratory drive can generate large transpulmonary pressure swings and worsen lung injury. Higher PEEP may mitigate this by reducing inspiratory effort and lung stress, but patient response is variable and difficult to predict. While improved lung compliance appears to mediate the protective effects of PEEP, its bedside assessment is complex. Preclinical data suggest that changes in compliance are inversely reflected by changes in respiratory rate, but this relationship and its clinical utility in ARDS patients remain unclear.

Detailed description

Spontaneous Breathing (SB) can be potentially harmful in patient with Acute Respiratory Distress Syndrome (ARDS) during the transition phase of passive ventilation to partial ventilatory support. A high respiratory drive and consequently, a strong inspiratory effort, may produce large transpulmonary pressure (TP) swings mainly in dependent lung regions closer to the diaphragm and cause alveolar rupture and inflammatory mediators release. The application of high Positive End Expiratory Pressure (PEEP) during SB has shown to ameliorate the progression of lung injury by decreasing the TP and esophageal pressure (EP) swings and the stress / strain applied to the lung. However, it is uncertain which patient will respond adequately to the application of high PEEP and consequently will reduce the inspiratory effort. Recent evidence suggests that high PEEP may confer protective effects when lung compliance improves. However, assessing lung compliance at the bedside is challenging, as it requires esophageal pressure monitoring. Simpler tools to identify lung compliance response to PEEP are neccesary. Preclinical data suggest that the changes in compliance are followed by opposite changes in respiratory rate (RR) - i.e., if compliance improves, RR decreases and vicerversa. However, if this behaviour is also observed in ARDS patients ventilated at different PEEP levels is unkown. Additionally, whether changes in RR can be useful to identify changes in lung compliance when increasing PEEP has never been tested.

Conditions

• Acute Respiratory Distress Syndrome

Interventions

Type	Name	Description
OTHER	Positive end expiratory pressure	Initially, the patients will be ventilated using pressure support ventilation with an inspiratory pressure adjusted to achieve 6 - 8 ml/kg of PBW with a minimal esophageal pressure swing of 5 cmH2O and a PEEP of 5 cmH2O. After 5 minutes, we will collect basic and advanced respiratory monitoring, including esophageal pressure and transpulmonary pressure swings. The same procedure will be carried out with 10 and 15 cmH2O of PEEP. Inspiratory pressure will be kept constant throughout the protocol.

Timeline

• Start date: 2020-08-01
• Primary completion: 2026-04-01
• Completion: 2026-08-01
• First posted: 2020-08-24
• Last updated: 2026-04-16

Locations

1 site across 1 country: Argentina