Modified HFNC Therapy for ARF Patients Undergoing Flexible Bronchoscopy

Study Overview
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Brief Summary
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Acute respiratory failure (AFR) is a serious condition that requires prompt and appropriate intervention to prevent further deterioration and improve outcomes. Bronchoscopy is a commonly used diagnostic and therapeutic procedure in patients with respiratory failure. However, traditional low-flow oxygen supplementation during bronchoscopy may not provide adequate oxygenation and ventilation, leading to complications and worsening of the patient's condition. High-flow nasal cannula therapy has improved oxygenation and ventilation in critically ill patients, making it a promising alternative to traditional oxygen supplementation during bronchoscopy. The bronchoscope is passed through the nose during all procedures in our center. HFNC oxygen therapy is applied to both nostrils. The bronchoscope occupies one of the nares receiving oxygen therapy during bronchoscopy. As a result, the application of HFNC needs to be optimized. Therefore, the investigators designed a modified HFNC with a single cannula. However, limited data exist on the safety and efficacy of modified HFNC therapy in patients with respiratory failure undergoing bronchoscopy. Therefore, the aim of this study is to evaluate the impact of modified HFNC therapy on the outcomes of undergoing bronchoscopy in patients with ARF. The findings of this study will contribute to understanding the role of modified HFNC therapy in managing ARF and inform clinical practice.

Official Title
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Modified Nasal High-flow Oxygen Therapy for Acute Respiratory Failure Patients Undergoing Flexible Bronchoscopy

Conditions
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Acute Hypoxemic Respiratory Failure, High-flow Nasal Cannula Oxygen

Intervention / Treatment
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* Device: Modified HFNC oxygen therapy
* Device: Face mask


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Age ≥ 18 years old; Bronchoscopy is required; 150 mmHg ≤ PaO2/FiO2 < 300 mmHg. Exclusion Criteria: Not tolerate HFNC oxygen therapy; Obstruction of nasopharynx cavity; Platelet<60 × 109/L； Need tracheal intubation; The patient has received invasive ventilation.

Ages Eligible for Study
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Minimum Age: 18 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Treatment
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Double


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Modified HFNC oxygen therapy group<br> | Device: Modified HFNC oxygen therapy<br>* In the modified HFNC group, high-flow devices (AIRVOTM 2; Fisher & Paykel Healthcare, Auckland, New Zealand) were utilized for respiratory support. The nasal cannula used was a modified single nasal cannula.<br>|
| Other: Face mask group<br> | Device: Face mask<br>* In the face mask group, oxygen was delivered via a face mask during bronchoscopy. The oxygen flow was set to achieve a saturation of pulse oxygen > 90%.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Need to increase ventilatory support | The proportion of patients needs to increase ventilatory support, including (1) upgrading respiratory support; (2) increasing parameters of non-invasive mechanical ventilation or modified HFNC. | Within 24 hours after bronchoscopy | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| The incidence of hypoxia during bronchoscopy | Hypoxia is defined as SpO2 < 90%. | During bronchoscopy |