Acute Hypoxemic Respiratory Failure
Conditions
Brief summary
The optimal noninvasive management of acute hypoxemic respiratory failure is debated. Helmet noninvasive ventilation may be more effective than facemask noninvasive ventilation for these patients. Putatitve benefits of helmet use are the possibility to apply significantly higher positive end-expiratory pressure without air leaks and with good patient's comfort. In this randomized crossover study, the investigators will assess the physiological effects of helmet compared to facemask noninvasive ventilation, with the latter applied with different ventilator settings (similar to or different from helmet settings).
Interventions
DEVICENoninvasive ventilation
noninvasive ventilation
Sponsors
Fondazione Policlinico Universitario Agostino Gemelli IRCCS
Study design
Allocation
RANDOMIZED
Intervention model
CROSSOVER
Primary purpose
TREATMENT
Masking
NONE
Intervention model description
Crossover randomized trial
Eligibility
Sex/Gender
ALL
Age
18 Years to No maximum
Healthy volunteers
No
Inclusion criteria
* Acute hypoxemic respiratory failure and PaO2/FiO2\<200 mmHg * PaCO2\<45 mmHg * Respiratory failure not caused by exacerbation of chronic pulmonary disease, cardiac failure or fluid overload
Exclusion criteria
* Pregnancy * Contraindication to helmet or facemask noninvasive ventilation * Contraindication to esophageal manometry * Contraindication to electrical-impedance tomography monitoring * Recent surgery involving the abdomen or the thorax * Pneumothorax or documented barotrauma
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Inspiratory effort | 1 hour | negative deflection in esophageal pressure |
| End-expiratory lung impedance | 1 hour | Electrical-impedance derived end-expiratory lung volume |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Respiratory rate | 1 hour | Respiratory rate per minute |
| Dynamic transpulmonary driving pressure | 1 hour | Tidal change in transpulmonary pressure |
| Compliance | 1 hour | Ratio of tidal volume to transpulmonary driving pressure |
| Dyspnea | 1 hour | Dyspnea rated through a visual analog scale (ranging from 0 to 10, with representing most severe dyspnea) adapted for critically ill patients |
| Discomfort | 1 hour | Device-related discomfort (ranging from 0 to 10, with representing most severe dyspnea) rated through a visual analog scale adapted for critically ill patients |
| Tidal volume | 1 hour | Electrical-impedance derived tidal volume size |
| Pendelluft extent | 1 hour | Pendelluft extent, expressed in % of the total tidal volume |
| Corrected minute ventilation | 1 hour | The product of tidal volume and respiratory rate, normalized to PaCO2. This value is expressed in Arbitrary units per minute divided by mmHg and is a proxy of dead space |
| Arteria Carbon dioxide tension | 1 hour | PaCO2 |
| Tidal volume distribution | 1 hour | Tidal volume distribution, assessed with electrical impedance tomography in 4 regions of interest (ventral, mid-ventral, mid-dorsal, dorsal) |
| Oxygenation | 1 hour | PaO2/FiO2 ratio |
| Work of breathing | 1 hour | Esophageal pressure simplified pressure-time product |
Countries
Italy
Outcome results
None listed