An interventional study of Apneic oxygenation and Usual Care in Hypoxemic Acute Respiratory Failure, sponsored by University Hospital, Tours. Not yet recruiting at 1 site in France. Open to participants aged 18 Years and older. Per ClinicalTrials.gov, last updated 2025-09-23.
Sponsored by University Hospital, Tours · Not applicable, Interventional, and Prevention
The aim of this clinical study is to assess whether apneic oxygenation with High-Flow Nasal Oxygen (HFNO) would decrease the incidence of severe hypoxemia compared to no apneic oxygenation during the intubation procedure (from the start of laryngoscopy to 5 minutes after successful intubation) in patients with hypoxemic acute respiratory failure.
The sponsor expects that apneic oxygenation (between the laryngoscopy and the success of intubation) with HFNO compared to no apneic oxygenation could decrease the risk of severe hypoxemia after intubation in hypoxemic critical ill patients.
Participants will be enrolled according to eligibility criteria and randomized into one of the following groups:
Experimental group : Apneic oxygenation will be used with HFNO between the laryngoscopy and the successful intubation (study intervention).
non-invasive ventilation (NIV) alone will be used for the preoxygenation and hypoventilation phase until the laryngoscopy. The nasal cannulas of HFNO will be placed on hold beneath the patient's chin (with HFNO on and set with a flow at 60-70L.min-1, FiO2 1.0) pending laryngoscopy began.
At the time of laryngoscopy: after removing the facemask of NIV, the nasal cannulas for HFNO will be placed in the patient's nares then the laryngoscopy will be performed.
Control group: The control group will receive usual care, i.e., no oxygen during the apneic phase (between the laryngoscopy and the success of the intubation procedure) During the preoxygenation and hypoventilation phase until laryngoscopy, NIV alone will be used as in the experimental group.
Endotracheal intubation is often performed in intensive care unit (ICU). Severe complications (such as severe hypoxemia, hypotension, cardiac arrest) occur up to 50%. Severe hypoxemia is more frequent in patients with hypoxemia prior to intubation or during difficult intubation and could increase the risk of cardiac arrest.
The procedure of intubation includes, in order 1) a preoxygenation phase ending with iv administration of anesthetic drugs 2) a hypoventilation phase 3) an apneic phase beginning with laryngoscopy and ending with successful intubation 4) mechanical ventilation. Optimization of this procedure is essential.
Non-invasive ventilation (NIV) is recommended for preoxygenation in hypoxemic patients and this technique can maintain ventilation during the hypoventilation phase.
Apneic oxygenation is defined as the administration of oxygen during the apneic phase. The objective is to increase the duration of apnea without desaturation. In physiological studies and in the operating room, when apneic oxygen is used with standard oxygen (up to 15L/min) or high-flow nasal oxygenation (HFNO) (up to 70L/min and FiO2 at 1.0), the apnea length without desaturation can reach several minutes.
Several meta-analyses (with high heterogeneity between studies) found that apneic oxygenation (including standard oxygen or HFNO) in emergency intubation could decrease the risk of hypoxemia. In most studies that investigated the effect of HFNO as apneic oxygenation, HFNO was also used as a preoxygenation method. Thus, the different methods of preoxygenation could affect the real effect of apneic oxygenation.
Only one single-center study evaluated apneic oxygenation with HFNO after preoxygenation by NIV. In this study the lowest SpO2 during intubation procedure was significantly higher in the apneic oxygenation group. However, in this study the mask used for NIV was applied over the nasal cannulas of HFNO, which may have resulted in less efficient preoxygenation due to leakage.
Intubation rate for HFNO failure during acute respiratory failure is about 40% in ICU patients. The question of continuing HFNO or not during the apnea phase remains open. The experts suggest continuing HFNO during intubation (conditional recommendation, moderate certainty).
We hypothesized that apneic oxygenation (between the laryngoscopy and the success of intubation) with HFNO compared to no apneic oxygenation could decrease the risk of severe hypoxemia after intubation in hypoxemic critical ill patients.
In both groups, NIV will be used during the preoxygenation and hypoventilation phases.
Procedure of intubation will be standardized according to guidelines
Preoxygenation will be performed using NIV through a facemask in both group
At the time of laryngoscopy :
1,650 studies on the registry are indexed under Respiratory Insufficiency; 296 are open to participants now.
This study's planned enrollment of 500 is above the median of 55 across 1,043 interventional studies indexed under Respiratory Insufficiency.
Browse Respiratory Insufficiency studies →University Hospital, Tours is the lead sponsor of 304 studies on the registry; 78 are open to participants now.
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Indication of orotracheal intubation for Hypoxemic acute respiratory failure defined by:
Exclusion Criteria:
\< 18 years old
Apneic oxygenation will be used with HFNO between the laryngoscopy and the successful intubation (study intervention). NIV alone will be used for the preoxygenation and hypoventilation phase until the laryngoscopy. Apneic oxygenation will be used with HFNO at the time of laryngoscopy after removing the facemask of NIV (with HFNO on and set with a flow at 60-70L.min-1, FiO2 1.0)
Procedure: Apneic oxygenation
The control group will receive usual care, i.e., no oxygen during the apneic phase (between the laryngoscopy and the success of the intubation procedure) During the preoxygenation and hypoventilation phase until laryngoscopy, NIV alone will be used as in the experimental group.
Procedure: Usual Care
* Preoxygenation will be performed using NIV for 3-5 min With nasal cannulas placed in standby beneath the patient's chin (with HFNO on and set with a flow at 60-70L.min-1, FiO2 1.0) * Rapide sequence induction * Hypoventilation phase will be continue for 1 min using NIV * At the time of laryngoscopy : After removing the facemask, the nasal cannulas of HFNO will be placed in the patient's nares then the laryngoscopy will be performed. \* Use of capnography to confirm the success of procedure
* Preoxygenation will be performed using NIV for 3-5 min without HFNO * Rapide sequence induction * Hypoventilation phase will be continue using NIV for 1min * At the time of laryngoscopy : After removing the facemask, laryngoscopy will be performed without oxygen. \* Use of capnography to confirm the success of procedure
Incidence of severe hypoxemia
The incidence of severe hypoxemia defined as the occurrence of at least one episode of oxygen saturation measured by pulse oximetry (SpO2) \< 80%
Time frame: from the start of laryngoscopy to 5 minutes after successful intubation
Incidence of prolonged severe hypoxemia
The incidence of prolonged severe hypoxemia defined by an SpO2 \< 80% for more than 24 seconds
Time frame: from the start of laryngoscopy to 5 minutes after successful intubation
The highest and lowest SpO2 values during the procedure
The highest and lowest SpO2 values during the procedure
Time frame: from the start of laryngoscopy to 5 minutes after successful intubation
The occurrence of each immediate severe complications
The occurrence of each immediate severe complications including cardiovascular instability (systolic arterial blood pressure \<65 mmHg at least once, new or increase need of vasopressors or fluid bolus \>15 mL/kg), cardiac arrest, new onset cardiac arrhythmia (atrial fibrillation, ventricular tachycardia, bradycardia \<30beats per minute).
Time frame: from the start of laryngoscopy to 5 minutes after successful intubation
The occurrence of each other adverse events
The occurrence of each other adverse events: difficult intubation (defined as a procedure requiring more than 2 laryngoscopy attempts before success), operator-reported aspiration between induction and intubation, dental injury, esophageal intubation, pneumothorax visualized on the follow-up chest X-ray as part of the patient's routine care.
Time frame: from the start of laryngoscopy to 5 minutes after successful intubation; At Day 28
Duration of laryngoscopy
The duration of laryngoscopy will be compared in both group
Time frame: From the 1st attempt to the successful intubation
Number of laryngoscopies
The number of laryngoscopies will be compared in both group
Time frame: from the 1st attempt to the successful intubation
Day-28 mortality
Time frame: at Day 28
This study is not yet recruiting, as verified in Sep 2025. You cannot join it, but the record below documents what was studied.
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University Hospital, Tours