Acute Respiratory Failure (ARF)
Conditions
Keywords
ARF, HFNC, acute respiratory failure, weaning, ROX INDEX
Brief summary
High-flow nasal cannula (HFNC) is a widely used noninvasive respiratory support technique for patients with acute respiratory failure (ARF). It provides heated and humidified oxygen at high flow rates, improving oxygenation, reducing respiratory effort, and enhancing patient comfort. International guidelines recommend HFNC over conventional oxygen therapy in hypoxemic ARF. However, there is significant variability in clinical practice regarding HFNC discontinuation, and no standardized weaning criteria currently exist. Prolonged HFNC use may increase hospital stay and healthcare costs, while premature discontinuation may lead to respiratory deterioration and the need for further ventilatory support. Previous studies suggest that successful HFNC weaning may be predicted by a Fraction of inspired oxygen (FiO₂) ≤40% and a Respiratory rate-Oxygenation index (ROX index) ≥9.2. The ROX index is calculated as the ratio of peripheral oxygen saturation (SpO₂) divided by fraction of inspired oxygen (FiO₂) to respiratory rate. The primary objective of this study is to compare a standardized HFNC weaning strategy based on ROX index and FiO₂ thresholds with usual clinical practice based on physician judgment. The primary outcome is weaning failure at the first attempt, defined as the need for HFNC reinstitution, noninvasive or invasive mechanical ventilation, or death within 48 hours after discontinuation.
Interventions
OTHERProtocolized HFNC weaning
HFNC discontinuation based on ROX index ≥9.2 and FiO₂ ≤40%
Sponsors
University of Milan
Study design
Allocation
RANDOMIZED
Intervention model
PARALLEL
Primary purpose
OTHER
Masking
NONE
Eligibility
Sex/Gender
ALL
Age
18 Years to No maximum
Healthy volunteers
No
Inclusion criteria
* Age ≥18 years * Presence of acute respiratory failure (ARF) * Receiving HFNC treatment for ≥24 hours
Exclusion criteria
* Post-extubation HFNC use or tracheostomized patients * Respiratory acidosis (pH \<7.35) or clinically significant acute hypercapnia (pCO₂ \>50 mmHg with worsening from baseline) * Long-term home NIV or home CPAP use * Do-not-intubate (DNI) orders precluding escalation to invasive mechanical ventilation * Life expectancy ≤48-72 hours due to terminal non-respiratory disease * Neurological impairment or deep sedation preventing safe HFNC use (e.g. coma or severe uncontrolled delirium) * Technical contraindications to HFNC (i.e. facial trauma, maxillofacial surgery, severe nasal obstruction) * Refusal to participate or inability to provide informed consent
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Weaning failure | Within 48 hours after the first separation attempt | To compare the percentage of patients who fail HFNC weaning within 48 hours after the first separation attempt using a protocolized HFNC weaning strategy based on ROX index and FiO₂ cut-offs versus standard clinical practice guided by physician judgment. |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Second-attempt weaning success | Within 48 hours after the second separation attempt | To compare the percentage of patients who fail HFNC weaning within 48 hours after the second separation attempt using a protocolized HFNC weaning strategy based on ROX index and FiO₂ cut-offs versus standard clinical practice guided by physician judgment. |
| Length of hospital stay | From the day of hospital admission until the day of hospital discharge, assessed up to 60 days; and from the day of HFNC discontinuation until the day of hospital discharge, assessed up to 60 days. | Comparison of total hospital stay and post-weaning hospital stay between the two study arms. |
| In-hospital and 30-day mortality | From the day of admission to the day of discharge or death (in-hospital mortality) and from the day of admission to 30-day after discharge (30-day mortality) | Comparison of in-hospital mortality and 30-day mortality after discharge between the two study arms. |
| Predictors of weaning success | From enrollment through hospital discharge, an average of 10 days. | Identification of clinical and respiratory variables associated with successful HFNC weaning. |
| Number of days of HFNC treatment from initiation to definitive discontinuation | From the date and time of HFNC initiation until the date and time of definitive HFNC discontinuation, assessed up to 30 days. | Number of days of HFNC treatment from initiation to definitive discontinuation |
| Predictors of HFNC treatment duration | From HFNC initiation through hospital discharge, an average of 10 days | Demographic, clinical, radiological and laboratory variables associated with HFNC treatment duration |
| Prevalence of diaphragmatic dysfunction assessed by diaphragm thickening fraction (DTF) and diaphragmatic excursion measured by ultrasound between the two study arms. | 30 minutes before HFNC weaning initiation and 24 hours after weaning completion. | Comparison of the prevalence of diaphragmatic dysfunction assessed by diaphragmatic ultrasound between patients with successful HFNC weaning and those with weaning failure. Diaphragmatic function will be evaluated using diaphragm thickening fraction (DTF) and diaphragmatic excursion measured by ultrasound. |
| Changes in diaphragmatic function | Before HFNC discontinuation and within 48 hours after weaning attempt | Evaluation of diaphragmatic ultrasound parameters before and after HFNC discontinuation. |
Countries
Italy
Contacts
CONTACTMichele Mondoni, MD
Outcome results
None listed