Respiratory Failure
Conditions
Brief summary
This study evaluates the work of breathing among patients under various conditions of treatment with high flow nasal cannulas. Sixteen spontaneously breathing patients with respiratory failure (hypercapnic or hypoxemic) will be included. The design of this study is a cross over of four treatment periods with different flow settings.
Detailed description
High flow oxygen therapy (HFOT) is a promising technique increasingly used in the management of acute respiratory failure. In hospitalised hypoxemic patients, recent clinical evidence showed that HFOT can reduce endotracheal intubation and reduce mortality. Physiologically, the HFOT causes a decrease in respiratory rate and minute-ventilation and may be associated with a decrease in PaCO2. It is possible that these effects are associated with decreased work of breathing, which could explain some of the benefits in terms of comfort and efficiency. The objective of this research is to evaluate the impact of a wash-out of anatomical dead space by high flow nasal cannulas on respiratory parameters and on the work of breathing. The investigators will evaluate the baseline status with conventional oxygen therapy methods (low flows), and then compare it with three different levels of high flow oxygen therapy in a randomised order. The primary endpoint will be the work of breathing.
Interventions
DEVICEAirvo 2; Ficher and Paykel HealthCare
High flow nasal cannulas
DEVICEOxygen delivery via conventional nasal mask
Low flow of oxygen delivered through conventional nasal prongs
Sponsors
Laval University
Study design
Allocation
RANDOMIZED
Intervention model
CROSSOVER
Primary purpose
TREATMENT
Masking
SINGLE (Subject)
Eligibility
Sex/Gender
ALL
Age
18 Years to No maximum
Healthy volunteers
No
Inclusion criteria
Spontaneously breathing patients exhibiting a respiratory distress defined by a respiratory rate ≥ 20 breaths/min associated with * either hypoxemia (SpO2\<90% with O2≥3L/min) ; * or hypercapnia (PaCO2\>45 mmHg with a respiratory acidosis (pH\<7,38).
Exclusion criteria
* Patients below 18yo, pregnant or breastfeeding women; * Patients enrolled in another study excluding co-enrolment; * History of ear nose and throat disease (i.e. surgery, epistaxis, trauma), eso-gastric disease (i.e. esophageal varices, digestive haemorrhage), rheumatologic or neurologic disease possibly interfering with the design of the study; * Acute respiratory or cardiovascular disease contra-indicating the enrolment in the study protocol (i.e. acute coronary syndrome, pulmonary embolism, pneumothorax); * Need for immediate intubation or for continuous noninvasive ventilation and/or recent (\<6h) arterial blood gases showing a respiratory acidosis with a pH\<7.30; * Patient feeling nauseous or under recent fed condition (\<1h).
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Work of breathing | 15 minutes | Work of breathing at the end of each period is calculated from the measurement of esophageal pressure and tidal volume (composite outcome) |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Tidal volume | 15 minutes | Measured at the end of each period |
| Comfort of breathing | 15 minutes | Subjective evaluation at the end of each period |
| Blood gases | 15 minutes | Arterial or capillary blood gases at the end of each period |
| Dyspnea | 15 minutes | Evaluation on a borg scale at the end of each period |
| Esophageal pressure-time product | 15 minutes | Measured at the end of each period |
| Heart rate | 15 minutes | Measured at the end of each period |
| End-tidal carbon dioxide | 15 minutes | Measured at the end of each period |
| Oxygen saturation | 15 minutes | Measured at the end of each period |
| Respiratory rate | 15 minutes | Measured at the end of each period |
Countries
Canada
Contacts
Primary ContactMathieu Delorme, PT, MSc
Backup ContactFrançois Lellouche, MD, PhD
Outcome results
None listed