Diaphragm Injury, Lung Injury, Mechanical Ventilation Complication, Respiratory Insufficiency
Conditions
Keywords
Diaphragm Dysfunction, Acute Respiratory Failure, Sedation, Mechanical Ventilation, Lung Stress
Brief summary
This study is designed to test a proposed strategy for lung- and diaphragm-protective ventilation (LDPV) in patients with acute hypoxemic respiratory failure. Ventilation and sedation will be titrated to evaluate whether it is feasible and safe within this patient population.
Detailed description
Lung injury and diaphragm injury incurred by mechanical ventilation have very serious adverse effects on patients with acute respiratory failure. Lung injury results from excessive mechanical stress and strain applied to the lung by the ventilator and/or respiratory muscles, while diaphragm injury results from either insufficient or excessive inspiratory effort. The objective of this study is to investigate a new LDPV strategy designed to prevent both disuse-mediated and load-induced diaphragm injury, while also preventing excess global and regional mechanical stress and strain in the injured lung. To achieve these goals, the following specific targets to be met are: (1) respiratory muscle effort similar to that of healthy subjects breathing at rest, (2) lung stress within safe limits, and (3) clinically acceptable gas exchange. Targets are assessed through measurements of global lung stress, tidal recruitment, inspiratory effort, diaphragm contractile effort and adequacy of respiratory muscle and systemic tissue perfusion. Measurements commence at enrollment and continue for 24 hours consecutively.
Interventions
PROCEDURELung- and Diaphragm-Protective Ventilation
Ventilation and sedation will be progressively modified according to the LDPV algorithm to achieve targets. Patients will be crossed-over to the opposite PEEP strategy. LDPV titration will then be repeated to achieve LDPV targets. After establishing a combination of ventilation and sedation settings at which LDPV targets are achieved, the targets will be maintained over a 24-hour period.
Sponsors
University Health Network, Toronto
Study design
Allocation
RANDOMIZED
Intervention model
PARALLEL
Primary purpose
PREVENTION
Masking
NONE
Eligibility
Sex/Gender
ALL
Age
18 Years to No maximum
Healthy volunteers
No
Inclusion criteria
* Diagnosed with acute hypoxemic respiratory failure * PaO2:FiO2 ratio less than or equal to 300 mm Hg at time of screening * Oral endotracheal intubation and mechanical ventilation * Bilateral airspace opacities on chest radiograph or chest CT scan
Exclusion criteria
* Liberation from mechanical ventilation is anticipated within 24 hours * Intubated for traumatic brain injury or stroke * Contraindication to esophageal catheterization * Intracranial hypertension
Design outcomes
Primary
| Measure | Time frame |
|---|---|
| Rate of patients achieving and maintaining LDPV targets | Assessed after achievement of LDPV targets for 24 hours |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Expiratory diaphragmatic effort at lower and higher PEEP levels | Assessed 10 minutes after PEEP and sedation are adjusted | — |
| Lung stress and strain at low and high sweep gas flow rates | Assessed 10 minutes after PEEP and sedation are adjusted | — |
| Inspiratory effort at lower and higher PEEP levels | Assessed 10 minutes after PEEP and sedation are adjusted | — |
| Sedative infusion rate at low and high sweep gas flow rates | Assessed 10 minutes after PEEP and sedation are adjusted | — |
| Accuracy of artificial intelligence model in predicting patient outcomes | Assessed after completing the 24-hour maintenance period | We will compare the model's prediction of patient's esophageal pressure, pH and transpulmonary pressure to the actual observed values |
| Inspiratory effort at low and high sweep gas flow rates | Assessed 10 minutes after PEEP and sedation are adjusted | — |
Countries
Canada
Outcome results
None listed