Physiological Effects of Continuous Negative External Pressure for Acute Hypoxemic Respiratory Failure
For patients and families
In plain language
An automatic summary of structured registry data. It is an orientation aid, not a substitute for the official protocol or a physician assessment.
- What is being studied
- The protocol lists: HFNC only, HFNC + CNEP10, HFNC + CNEP20, HFNC + CNEP30.
- Who it may be relevant to
- Registry conditions: Acute Hypoxemic Respiratory Failure. Basic parameters: from 18 years · All.
- What needs checking
- Age, condition and sex are only basic indicators. Prior treatment, laboratory values and other mandatory requirements appear in the eligibility criteria below.
- Where it takes place
- United States
- Next step
- Save the trial, show it to the treating physician, and confirm current recruitment with the study center. Costs, documents and travel →
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Official title
Physiological Effects of Continuous Negative External Pressure for Acute Hypoxemic Respiratory Failure: A Pilot Crossover Trial
Overview
This study is being conducted to evaluate if wearing a non-invasive breathing support device over the chest/abdomen improves markers of breathing in patients with lung injury requiring high-flow oxygen. The breathing support device consists of a plastic shell that sits over the chest and abdomen and connects to a vacuum that helps the chest expand with breathing. This breathing support is known as continuous negative external pressure (CNEP). Study findings will help determine if this breathing support device might be useful for patients with acute hypoxemic respiratory failure (AHRF).
Detailed description
This study is a prospective randomized cross-over trial. Eligible, consenting participants will undergo 4 strategies of respiratory support: high-flow nasal cannula (HFNC) only, HFNC + continuous negative external pressure (CNEP) of 10 cmH2O, HFNC + CNEP of 20 cmH2O, HFNC + CNEP of 30 cmH2O. Throughout the study period, HFNC will be managed at a constant flow rate with fraction of inspired oxygen (FiO2) titrated to achieve goal oxygen saturation (SpO2) of 90-97%, measured via continuous pulse-oximetry. Each of the 4 strategies will be performed for 45 minutes per strategy, interspersed with a 15-minute washout period of HFNC only. Participants will be randomized to the sequence of strategies for respiratory support.
A summary of the sequence of trial procedures is as follows:
1. Perform baseline measures. 2. Wait 5-10 minutes for recovery. 3. Initiate first random treatment assignment for up to 45 minutes. 4. HFNC-only washout for 15 minutes 5. Initiate second random treatment assignment for up to 45 minutes. 6. HFNC-only washout for 15 minutes 7. Initiate third random treatment assignment for up to 45 minutes. 8. HFNC-only washout for 15 minutes 9. Initiate fourth random treatment assignment for up to 45 minutes. 10. Return to usual care (HFNC only)
If a participant does not tolerate a given level of CNEP, the patient will be returned to HFNC for 5 minutes and then given the option to attempt that CNEP level again. If the patient declines reattempt or does not tolerate that CNEP level on reattempt, the HFNC-only washout will be instituted for 15 minutes before proceeding to the next protocol step.
Interventions
- Device HFNC only
HFNC for 45 minutes, with FiO2 titrated to SpO2 of 90-97% - Device HFNC + CNEP10
HFNC with CNEP of 10 cmH2O for 45 minutes, with FiO2 titrated to SpO2 of 90-97% - Device HFNC + CNEP20
HFNC with CNEP of 20 cmH2O for 45 minutes, with FiO2 titrated to SpO2 of 90-97% - Device HFNC + CNEP30
HFNC with CNEP of 30 cmH2O for 45 minutes, with FiO2 titrated to SpO2 of 90-97%
Primary outcome measures
- Change from baseline in SpO2/FiO2 [Time frame: At the end of each treatment period, up to 45 minutes]
Secondary outcome measures (12)
- Change from baseline in Respiratory Rate [Time frame: At the end of each treatment period, up to 45 minutes]
- Change from baseline in ROX Index [Time frame: At the end of each treatment period, up to 45 minutes]
- Change from baseline in Transcutaneous Carbon Dioxide (CO2) [Time frame: At the end of each treatment period, up to 45 minutes]
- Change from baseline in Heart Rate [Time frame: At the end of each treatment period, up to 45 minutes]
- Change from baseline in Blood Pressure [Time frame: At the end of each treatment period, up to 45 minutes]
- Change from baseline in Breathing Discomfort [Time frame: At the end of each treatment period, up to 45 minutes]
- Change from baseline in Lightheadedness [Time frame: At the end of each treatment period, up to 45 minutes]
- Change from baseline in Nausea [Time frame: At the end of each treatment period, up to 45 minutes]
- Change from baseline in Skin Discomfort [Time frame: At the end of each treatment period, up to 45 minutes]
- Change from baseline in Skin Erythema [Time frame: At the end of each treatment period, up to 45 minutes]
- Tolerance of intervention period [Time frame: For the duration of each treatment period, up to 45 minutes]
- Proportion of time within 3 cm H2O of target CNEP level [Time frame: For the duration of each treatment period, up to 45 minutes]
Eligibility criteria
Inclusion criteria
- Age 18 years or older
- Acute hypoxemic respiratory failure
- Non-cardiogenic airspace opacities on chest radiograph or computed tomography (CT) scan
- High-flow nasal cannula (flow ≥ 30 LPM) initiated within last 96 hours (4 days)
- FiO2 ≥ 40%
- SpO2 ≥ 92%
Exclusion criteria
- Do-not-intubate order
- Anatomical factor predisposing to poor fit of cuirass (e.g. severe kyphosis or scoliosis)
- Use of cuirass precluded, e.g. due to:
- Clinically prescribed prone positioning
- Tense ascites
- Severe abdominal pain
- Abdominal wound or surgery
- Pregnancy
- Agitated delirium
- Prior intubation during hospital stay
- Cardiogenic pulmonary edema
- Exacerbation of asthma or COPD
- Chronic lung disease, including:
- Interstitial lung disease
- Cystic fibrosis
- Lung mass, lung cancer, or metastasis to the lung
- Lung transplant recipient
- Any disease that requires home oxygen
- Glasgow coma score < 15
- Chest tube, pneumothorax, or pneumomediastinum
- Hemodynamic instability (mean arterial pressure < 55 mmHg or norepinephrine-equivalent vasopressor requirement > 0.1mcg/kg/min)
- Implantable electrical device (e.g. pacemaker, defibrillator, neurostimulator)
- Unreliable pulse-oximetry tracing
- Imminent intubation
- Anticipated lack of patient availability to complete study procedures (e.g. due to planned clinical procedure such as CT scan or dialysis during potential time of study)
- Attending physician refusal
Criteria are shown verbatim from the registry (in English). Final eligibility is always assessed by the study center.
Healthy volunteers: No
Study design
- Allocation
- Randomized
- Model
- Crossover
- Masking
- Open label
- Primary purpose
- Treatment
Study locations
United States · 1 center
- Columbia University Irving Medical Center — New York
Identifiers
NCT: NCT05675345 · AAAT7361