Comparative Study on the Effectiveness, Comfort and Compliance of HFNC and Noninvasive Mechanical Ventilation BiPAP Mode in the Treatment of Hypoxemia Patients

Study Overview
=================
Brief Summary
-----------------
Patients who met the inclusion criteria were included and signed an informed consent form, which complied with the requirements of the ethics committee of our unit. All subjects were inpatients. Subjects were randomized into two groups. patients in group A were first treated with HFNC on top of conventional treatment, and after 24 hours, patients were treated with non-invasive ventilator-assisted ventilation BiPAP mode until discharge. patients in group B were treated with a non-invasive ventilator on top of conventional treatment, and after 24 hours of treatment, patients were treated with HFNC until discharge. Patient information was collected during treatment.

Detailed Description
-----------------
Patients who met the inclusion criteria were included and signed the informed consent, which met the requirements of the ethics committee of our unit. All subjects were hospitalized patients. Subjects were randomly divided into two groups. Patients in group A were treated with HFNC on the basis of conventional treatment. The initial parameters were: temperature:31-37℃, flow: 30-40l /min, SpO2 > 92% maintained, the oxygen concentration was adjusted according to the patient's oxygen saturation, and the treatment time was 24h. Twenty-four hours later, the patients were treated with non-invasive ventilator-assisted ventilation BiPAP mode until discharge. On the basis of conventional treatment, patients in group B were given a non-invasive ventilator with the following initial parameters: BiPaP mode, initial inspiratory pressure (IPAP) of 8-15cmH2O, initial expiratory pressure (EPAP) of 4-8cmH2O. The parameters were adjusted according to the specific conditions of the patients. After 24 hours of treatment, the patient was treated with HFNC until discharge. Patient information was collected during treatment.

Official Title
-----------------
Comparative Study on the Effectiveness, Comfort and Compliance of High-flow Nasal Oxygen Therapy and Noninvasive Mechanical Ventilation BiPAP Mode in the Treatment of Hypoxemia Patients

Conditions
-----------------
Hypoxemia

Intervention / Treatment
-----------------
* Device: Non-invasive BiPAP ventilation
* Device: HFNC


Participation Criteria
=================
Eligibility Criteria
-----------------
Inclusion Criteria: . PaO2 < 60mmHg, SpO2 < 92%(without oxygen inhalation); Mild to moderate type I respiratory failure (100 mmHg < PaO/Fi02≤300 mmHg); Exclusion Criteria: Missing primary outcome measures Terminal stage of various chronic diseases; The patient or family members do not agree to NIV or HFNI treatment; Severe type I respiratory failure (PaO2/Fi02≤100 mmHg) Ventilation dysfunction (pH<7.30) Contradictory breathing The patient abandons or terminates treatment, automatically discharges or transfers to another hospital; Serious diseases, such as organ function damage and sepsis;

Ages Eligible for Study
-----------------
Minimum Age: 20 Years
Maximum Age: 80 Years

Sexes Eligible for Study
-----------------
All

Accepts Healthy Volunteers
-----------------
No

Study Plan
=================
How is the study designed?
-----------------

Design Details

Primary Purpose: Treatment
Allocation: Randomized
Intervention Model: Crossover Assignment
Masking: Single


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Non-invasive BiPAP ventilation treatment group<br>Patients were first treated with HFNC on the basis of conventional treatment. The initial parameters were temperature: 31-37 °C, flow rate: 30-40 L/min, maintaining SpO2>92%, adjusting oxygen concentration according to blood oxygen saturation, and treatment duration was 24 h. After 24 h, patients were treated with non-invasive ventilator-assisted ventilation BiPAP mode until discharge | Device: Non-invasive BiPAP ventilation<br>* Patients were first treated with HFNC (High-flow nasal cannula) on the basis of conventional treatment. The initial parameters were temperature: 31-37 °C, flow rate: 30-40l /min, maintaining SpO2>92%, adjusting oxygen concentration according to blood oxygen saturation, and treatment duration was 24 h. After 24 h, patients were treated with non-invasive ventilator-assisted ventilation BiPAP mode until discharge.<br>* Other names: HFNC;Device: HFNC<br>* On the basis of conventional treatment, patients were first administered a noninvasive ventilator with the following initial parameters. BiPAP mode with an initial inspiratory pressure (IPAP) of 8-15 cmH2O and an initial expiratory pressure (EPAP) of 4-8 cmH2O. These parameters were adjusted according to the patient's specific conditions. After 24 hours of treatment, patients received HFNC (High-flow nasal cannula) until discharge.<br>* Other names: Non-invasive BiPAP ventilation;|
| Experimental: HFNC treatment group<br>On the basis of conventional treatment, patients were first administered a noninvasive ventilator with the following initial parameters. BiPAP mode with an initial inspiratory pressure (IPAP) of 8-15 cmH2O and an initial expiratory pressure (EPAP) of 4-8 cmH2O. These parameters were adjusted according to the patient's specific conditions. After 24 hours of treatment, patients received HFNC until discharge. | Device: Non-invasive BiPAP ventilation<br>* Patients were first treated with HFNC (High-flow nasal cannula) on the basis of conventional treatment. The initial parameters were temperature: 31-37 °C, flow rate: 30-40l /min, maintaining SpO2>92%, adjusting oxygen concentration according to blood oxygen saturation, and treatment duration was 24 h. After 24 h, patients were treated with non-invasive ventilator-assisted ventilation BiPAP mode until discharge.<br>* Other names: HFNC;Device: HFNC<br>* On the basis of conventional treatment, patients were first administered a noninvasive ventilator with the following initial parameters. BiPAP mode with an initial inspiratory pressure (IPAP) of 8-15 cmH2O and an initial expiratory pressure (EPAP) of 4-8 cmH2O. These parameters were adjusted according to the patient's specific conditions. After 24 hours of treatment, patients received HFNC (High-flow nasal cannula) until discharge.<br>* Other names: Non-invasive BiPAP ventilation;|

What is the study measuring?
-----------------
Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| HR | Heart rate | At the time of enrollment in the clinical study | 
| HR | Heart rate | On the first hour after enrollment | 
| HR | Heart rate | On the second hour after enrollment | 
| HR | Heart rate | On the 6th hour after enrollment | 
| HR | Heart rate | On the 12th hour after enrollment | 
| HR | Heart rate | On the 24th hour after enrollment | 
| HR | Heart rate | On the 25th hour after enrollment (On the first hour after crossover) | 
| HR | Heart rate | On the 26th hour after enrollment (On the second hour after crossover) | 
| HR | Heart rate | On the 30th hour after enrollment (On the 6th hour after crossover) | 
| HR | Heart rate | On the 36th hour after enrollment (On the 12th hour after crossover) | 
| HR | Heart rate | On the 48th hour after enrollment (On the 24th hour after crossover) | 
| HR | Heart rate | On the third day after enrollment (On the 48th hour after crossover) | 
| HR | Heart rate | On the 4th day after enrollment (On the third day after crossover) | 
| HR | Heart rate | On the 5th day after enrollment (On the 4th day after crossover) | 
| HR | Heart rate | On the 6th day after enrollment (On the 5th day after crossover) | 
| HR | Heart rate | On the 7th day after enrollment (On the 6th day after crossover) | 
| HR | Heart rate | On the 8th day after enrollment (On the 7th day after crossover) | 
| HR | Heart rate | On the 9th day after enrollment (On the 8th day after crossover) | 
| RR | Respiratory rate | At the time of enrollment in the clinical study | 
| RR | Respiratory rate | On the first hour after enrollment | 
| RR | Respiratory rate | On the second hour after enrollment | 
| RR | Respiratory rate | On the 6th hour after enrollment | 
| RR | Respiratory rate | On the 12th hour after enrollment | 
| RR | Respiratory rate | On the 24th hour after enrollment | 
| RR | Respiratory rate | On the 25th hour after enrollment (On the first hour after crossover) | 
| RR | Respiratory rate | On the 26th hour after enrollment (On the second hour after crossover) | 
| RR | Respiratory rate | On the 30th hour after enrollment (On the 6th hour after crossover) | 
| RR | Respiratory rate | On the 36th hour after enrollment (On the 12th hour after crossover) | 
| RR | Respiratory rate | On the 48th hour after enrollment (On the 24th hour after crossover) | 
| RR | Respiratory rate | On the third day after enrollment (On the 48th hour after crossover) | 
| RR | Respiratory rate | On the 4th day after enrollment (On the third day after crossover) | 
| RR | Respiratory rate | On the 5th day after enrollment (On the 4th day after crossover) | 
| RR | Respiratory rate | On the 6th day after enrollment (On the 5th day after crossover) | 
| RR | Respiratory rate | On the 7th day after enrollment (On the 6th day after crossover) | 
| RR | Respiratory rate | On the 8th day after enrollment (On the 7th day after crossover) | 
| RR | Respiratory rate | On the 9th day after enrollment (On the 8th day after crossover) | 
| BP | Blood pressure (Includes systolic and diastolic blood pressure) | At the time of enrollment in the clinical study | 
| BP | Blood pressure (Includes systolic and diastolic blood pressure) | On the first hour after enrollment | 
| BP | Blood pressure (Includes systolic and diastolic blood pressure) | On the second hour after enrollment | 
| BP | Blood pressure (Includes systolic and diastolic blood pressure) | On the 6th hour after enrollment | 
| BP | Blood pressure (Includes systolic and diastolic blood pressure) | On the 12th hour after enrollment | 
| BP | Blood pressure (Includes systolic and diastolic blood pressure) | On the 24th hour after enrollment | 
| BP | Blood pressure (Includes systolic and diastolic blood pressure) | On the 25th hour after enrollment (On the first hour after crossover) | 
| BP | Blood pressure (Includes systolic and diastolic blood pressure) | On the 26th hour after enrollment (On the second hour after crossover) | 
| BP | Blood pressure (Includes systolic and diastolic blood pressure) | On the 30th hour after enrollment (On the 6th hour after crossover) | 
| BP | Blood pressure (Includes systolic and diastolic blood pressure) | On the 36th hour after enrollment (On the 12th hour after crossover) | 
| BP | Blood pressure (Includes systolic and diastolic blood pressure) | On the 48th hour after enrollment (On the 24th hour after crossover) | 
| BP | Blood pressure (Includes systolic and diastolic blood pressure) | On the third day after enrollment (On the 48th hour after crossover) | 
| BP | Blood pressure (Includes systolic and diastolic blood pressure) | On the 4th day after enrollment (On the third day after crossover) | 
| BP | Blood pressure (Includes systolic and diastolic blood pressure) | On the 5th day after enrollment (On the 4th day after crossover) | 
| BP | Blood pressure (Includes systolic and diastolic blood pressure) | On the 6th day after enrollment (On the 5th day after crossover) | 
| BP | Blood pressure (Includes systolic and diastolic blood pressure) | On the 7th day after enrollment (On the 6th day after crossover) | 
| BP | Blood pressure (Includes systolic and diastolic blood pressure) | On the 8th day after enrollment (On the 7th day after crossover) | 
| BP | Blood pressure (Includes systolic and diastolic blood pressure) | On the 9th day after enrollment (On the 8th day after crossover) | 
| SO2 | Pulse oxygen saturation | At the time of enrollment in the clinical study | 
| SO2 | Pulse oxygen saturation | On the first hour after enrollment | 
| SO2 | Pulse oxygen saturation | On the second hour after enrollment | 
| SO2 | Pulse oxygen saturation | On the 6th hour after enrollment | 
| SO2 | Pulse oxygen saturation | On the 12th hour after enrollment | 
| SO2 | Pulse oxygen saturation | On the 24th hour after enrollment | 
| SO2 | Pulse oxygen saturation | On the 25th hour after enrollment (On the first hour after crossover) | 
| SO2 | Pulse oxygen saturation | On the 26th hour after enrollment (On the second hour after crossover) | 
| SO2 | Pulse oxygen saturation | On the 30th hour after enrollment (On the 6th hour after crossover) | 
| SO2 | Pulse oxygen saturation | On the 36th hour after enrollment (On the 12th hour after crossover) | 
| SO2 | Pulse oxygen saturation | On the 48th hour after enrollment (On the 24th hour after crossover) | 
| SO2 | Pulse oxygen saturation | On the third day after enrollment (On the 48th hour after crossover) | 
| SO2 | Pulse oxygen saturation | On the 4th day after enrollment (On the third day after crossover) | 
| SO2 | Pulse oxygen saturation | On the 5th day after enrollment (On the 4th day after crossover) | 
| SO2 | Pulse oxygen saturation | On the 6th day after enrollment (On the 5th day after crossover) | 
| SO2 | Pulse oxygen saturation | On the 7th day after enrollment (On the 6th day after crossover) | 
| SO2 | Pulse oxygen saturation | On the 8th day after enrollment (On the 7th day after crossover) | 
| SO2 | Pulse oxygen saturation | On the 9th day after enrollment (On the 8th day after crossover) | 
| pH | Degree of pH in arterial blood | At the time of enrollment in the clinical study | 
| pH | Degree of pH in arterial blood | On the 24th hour after enrollment | 
| pH | Degree of pH in arterial blood | On the 48th hour after enrollment (On the 24th hour after crossover) | 
| pH | Degree of pH in arterial blood | On the third day after enrollment (On the 48th hour after crossover) | 
| pH | Degree of pH in arterial blood | On the 4th day after enrollment (On the 3th day after crossover) | 
| pH | Degree of pH in arterial blood | On the 5th day after enrollment (On the 4th day after crossover) | 
| pH | Degree of pH in arterial blood | On the 6th day after enrollment (On the 5th day after crossover) | 
| pH | Degree of pH in arterial blood | On the 7th day after enrollment (On the 6th day after crossover) | 
| pH | Degree of pH in arterial blood | On the 8th day after enrollment (On the 7th day after crossover) | 
| pH | Degree of pH in arterial blood | On the 9th day after enrollment (On the 8th day after crossover) | 
| PaO2 | Partial arterial oxygen pressure | At the time of enrollment in the clinical study | 
| PaO2 | Partial arterial oxygen pressure | On the 24th hour after enrollment | 
| PaO2 | Partial arterial oxygen pressure | On the 48th hour after enrollment (On the 24th hour after crossover) | 
| PaO2 | Partial arterial oxygen pressure | On the third day after enrollment (On the 48th hour after crossover) | 
| PaO2 | Partial arterial oxygen pressure | On the 4th day after enrollment (On the 3th day after crossover) | 
| PaO2 | Partial arterial oxygen pressure | On the 5th day after enrollment (On the 4th day after crossover) | 
| PaO2 | Partial arterial oxygen pressure | On the 6th day after enrollment (On the 5th day after crossover) | 
| PaO2 | Partial arterial oxygen pressure | On the 7th day after enrollment (On the 6th day after crossover) | 
| PaO2 | Partial arterial oxygen pressure | On the 8th day after enrollment (On the 7th day after crossover) | 
| PaO2 | Partial arterial oxygen pressure | On the 9th day after enrollment (On the 8th day after crossover) | 
| SaO2 | Arterial oxygen saturation | At the time of enrollment in the clinical study | 
| SaO2 | Arterial oxygen saturation | On the 24th hour after enrollment | 
| SaO2 | Arterial oxygen saturation | On the 48th hour after enrollment (On the 24th hour after crossover) | 
| SaO2 | Arterial oxygen saturation | On the third day after enrollment (On the 48th hour after crossover) | 
| SaO2 | Arterial oxygen saturation | On the 4th day after enrollment (On the third day after crossover) | 
| SaO2 | Arterial oxygen saturation | On the 5th day after enrollment (On the 4th day after crossover) | 
| SaO2 | Arterial oxygen saturation | On the 6th day after enrollment (On the 5th day after crossover) | 
| SaO2 | Arterial oxygen saturation | On the 7th day after enrollment (On the 6th day after crossover) | 
| SaO2 | Arterial oxygen saturation | On the 8th day after enrollment (On the 7th day after crossover) | 
| SaO2 | Arterial oxygen saturation | On the 9th day after enrollment (On the 8th day after crossover) | 
| PCO2 | partial pressure of carbon dioxide in arterial blood | At the time of enrollment in the clinical study | 
| PCO2 | partial pressure of carbon dioxide in arterial blood | On the 24th hour after enrollment | 
| PCO2 | partial pressure of carbon dioxide in arterial blood | On the 48th hour after enrollment (On the 24th hour after crossover) | 
| PCO2 | partial pressure of carbon dioxide in arterial blood | On the third day after enrollment (On the 48th hour after crossover) | 
| PCO2 | partial pressure of carbon dioxide in arterial blood | On the 4th day after enrollment (On the third day after crossover) | 
| PCO2 | partial pressure of carbon dioxide in arterial blood | On the 5th day after enrollment (On the 4th day after crossover) | 
| PCO2 | partial pressure of carbon dioxide in arterial blood | On the 6th day after enrollment (On the 5th day after crossover) | 
| PCO2 | partial pressure of carbon dioxide in arterial blood | On the 7th day after enrollment (On the 6th day after crossover) | 
| PCO2 | partial pressure of carbon dioxide in arterial blood | On the 8th day after enrollment (On the 7th day after crossover) | 
| PCO2 | partial pressure of carbon dioxide in arterial blood | On the 9th day after enrollment (On the 8th day after crossover) | 
| FiO2 | Fraction of inspiration O2 | At the time of enrollment in the clinical study | 
| FiO2 | Fraction of inspiration O2 | On the 24th hour after enrollment | 
| FiO2 | Fraction of inspiration O2 | On the 48th hour after enrollment (On the 24th hour after crossover) | 
| FiO2 | Fraction of inspiration O2 | On the third day after enrollment (On the 48th hour after crossover) | 
| FiO2 | Fraction of inspiration O2 | On the 4th day after enrollment (On the third day after crossover) | 
| FiO2 | Fraction of inspiration O2 | On the 5th day after enrollment (On the 4th day after crossover) | 
| FiO2 | Fraction of inspiration O2 | On the 6th day after enrollment (On the 5th day after crossover) | 
| FiO2 | Fraction of inspiration O2 | On the 7th day after enrollment (On the 6th day after crossover) | 
| FiO2 | Fraction of inspiration O2 | On the 8th day after enrollment (On the 7th day after crossover) | 
| FiO2 | Fraction of inspiration O2 | On the 9th day after enrollment (On the 8th day after crossover) | 
| Lac | Lactic acid in arterial blood | At the time of enrollment in the clinical study | 
| Lac | Lactic acid in arterial blood | On the 24th hour after enrollment | 
| Lac | Lactic acid in arterial blood | On the 48th hour after enrollment (On the 24th hour after crossover) | 
| Lac | Lactic acid in arterial blood | On the third day after enrollment (On the 48th hour after crossover) | 
| Lac | Lactic acid in arterial blood | On the 4th day after enrollment (On the third day after crossover) | 
| Lac | Lactic acid in arterial blood | On the 5th day after enrollment (On the 4th day after crossover) | 
| Lac | Lactic acid in arterial blood | On the 6th day after enrollment (On the 5th day after crossover) | 
| Lac | Lactic acid in arterial blood | On the 7th day after enrollment (On the 6th day after crossover) | 
| Lac | Lactic acid in arterial blood | On the 8th day after enrollment (On the 7th day after crossover) | 
| Lac | Lactic acid in arterial blood | On the 9th day after enrollment (On the 8th day after crossover) | 
| Glu | Arterial blood glucose in arterial blood | At the time of enrollment in the clinical study | 
| Glu | Arterial blood glucose in arterial blood | On the 24th hour after enrollment | 
| Glu | Arterial blood glucose in arterial blood | On the 48th hour after enrollment (On the 24th hour after crossover) | 
| Glu | Arterial blood glucose in arterial blood | On the third day after enrollment (On the 48th hour after crossover) | 
| GLu | Arterial blood glucose in arterial blood | On the 4th day after enrollment (On the third day after crossover) | 
| Glu | Arterial blood glucose in arterial blood | On the 5th day after enrollment (On the 4th day after crossover) | 
| Glu | Arterial blood glucose in arterial blood | On the 6th day after enrollment (On the 5th day after crossover) | 
| Glu | Arterial blood glucose in arterial blood | On the 7th day after enrollment (On the 6th day after crossover) | 
| Glu | Arterial blood glucose in arterial blood | On the 8th day after enrollment (On the 7th day after crossover) | 
| Glu | Arterial blood glucose in arterial blood | On the 9th day after enrollment (On the 8th day after crossover) | 
| A-aDO2 | The difference between the oxygen partial pressure of alveolar air and the oxygen partial pressure of arterial blood | At the time of enrollment in the clinical study | 
| A-aDO2 | The difference between the oxygen partial pressure of alveolar air and the oxygen partial pressure of arterial blood | On the 24th hour after enrollment | 
| A-aDO2 | The difference between the oxygen partial pressure of alveolar air and the oxygen partial pressure of arterial blood | On the 48th hour after enrollment (On the 24th hour after crossover) | 
| A-aDO2 | The difference between the oxygen partial pressure of alveolar air and the oxygen partial pressure of arterial blood | On the third day after enrollment (On the 48th hour after crossover) | 
| A-aDO2 | The difference between the oxygen partial pressure of alveolar air and the oxygen partial pressure of arterial blood | On the 4th day after enrollment (On the third day after crossover) | 
| A-aDO2 | The difference between the oxygen partial pressure of alveolar air and the oxygen partial pressure of arterial blood | On the 5th day after enrollment (On the 4th day after crossover) | 
| A-aDO2 | The difference between the oxygen partial pressure of alveolar air and the oxygen partial pressure of arterial blood | On the 6th day after enrollment (On the 5th day after crossover) | 
| A-aDO2 | The difference between the oxygen partial pressure of alveolar air and the oxygen partial pressure of arterial blood | On the 7th day after enrollment (On the 6th day after crossover) | 
| A-aDO2 | The difference between the oxygen partial pressure of alveolar air and the oxygen partial pressure of arterial blood | On the 8th day after enrollment (On the 7th day after crossover) | 
| A-aDO2 | The difference between the oxygen partial pressure of alveolar air and the oxygen partial pressure of arterial blood | On the 9th day after enrollment (On the 8th day after crossover) | 
| BE | Base excess in arterial blood | At the time of enrollment in the clinical study | 
| BE | Base excess in arterial blood | On the 24th hour after enrollment | 
| BE | Base excess in arterial blood | On the 48th hour after enrollment (On the 24th hour after crossover) | 
| BE | Base excess in arterial blood | On the third day after enrollment (On the 48th hour after crossover) | 
| BE | Base excess in arterial blood | On the 4th day after enrollment (On the third day after crossover) | 
| BE | Base excess in arterial blood | On the 5th day after enrollment (On the 4th day after crossover) | 
| BE | Base excess in arterial blood | On the 6th day after enrollment (On the 5th day after crossover) | 
| BE | Base excess in arterial blood | On the 7th day after enrollment (On the 6th day after crossover) | 
| BE | Base excess in arterial blood | On the 8th day after enrollment (On the 7th day after crossover) | 
| BE | Base excess in arterial blood | On the 9th day after enrollment (On the 8th day after crossover) | 
| RI | Respiratory Index | At the time of enrollment in the clinical study | 
| RI | Respiratory Index | On the 24th hour after enrollment | 
| RI | Respiratory Index | On the 48th hour after enrollment (On the 24th hour after crossover) | 
| RI | Respiratory Index | On the third day after enrollment (On the 48th hour after crossover) | 
| RI | Respiratory Index | On the 4th day after enrollment (On the third day after crossover) | 
| RI | Respiratory Index | On the 5th day after enrollment (On the 4th day after crossover) | 
| RI | Respiratory Index | On the 6th day after enrollment (On the 5th day after crossover) | 
| RI | Respiratory Index | On the 7th day after enrollment (On the 6th day after crossover) | 
| RI | Respiratory Index | On the 8th day after enrollment (On the 7th day after crossover) | 
| RI | Respiratory Index | On the 9th day after enrollment (On the 8th day after crossover) | 
| Arterial blood HCO3- concentration | Arterial blood HCO3- concentration，including arterial blood HCO3- std concentration | At the time of enrollment in the clinical study | 
| Arterial blood HCO3- concentration | Arterial blood HCO3- concentration，including arterial blood HCO3- std concentration | On the 24th hour after enrollment | 
| Arterial blood HCO3- concentration | Arterial blood HCO3- concentration，including arterial blood HCO3- std concentration | On the 48th hour after enrollment (On the 24th hour after crossover) | 
| Arterial blood HCO3- concentration | Arterial blood HCO3- concentration，including arterial blood HCO3- std concentration | On the third day after enrollment (On the 48th hour after crossover) | 
| Arterial blood HCO3- concentration | Arterial blood HCO3- concentration，including arterial blood HCO3- std concentration | On the 4th day after enrollment (On the third day after crossover) | 
| Arterial blood HCO3- concentration | Arterial blood HCO3- concentration，including arterial blood HCO3- std concentration | On the 5th day after enrollment (On the 4th day after crossover) | 
| Arterial blood HCO3- concentration | Arterial blood HCO3- concentration，including arterial blood HCO3- std concentration | On the 6th day after enrollment (On the 5th day after crossover) | 
| Arterial blood HCO3- concentration | Arterial blood HCO3- concentration，including arterial blood HCO3- std concentration | On the 7th day after enrollment (On the 6th day after crossover) | 
| Arterial blood HCO3- concentration | Arterial blood HCO3- concentration，including arterial blood HCO3- std concentration | On the 8th day after enrollment (On the 7th day after crossover) | 
| Arterial blood HCO3- concentration | Arterial blood HCO3- concentration，including arterial blood HCO3- std concentration | On the 9th day after enrollment (On the 8th day after crossover) | 
| Arterial blood K+ concentration | Arterial blood K+ concentration | At the time of enrollment in the clinical study | 
| Arterial blood K+ concentration | Arterial blood K+ concentration | On the 24th hour after enrollment | 
| Arterial blood K+ concentration | Arterial blood K+ concentration | On the 48th hour after enrollment (On the 24th hour after crossover) | 
| Arterial blood K+ concentration | Arterial blood K+ concentration | On the third day after enrollment (On the 48th hour after crossover) | 
| Arterial blood K+ concentration | Arterial blood K+ concentration | On the 4th day after enrollment (On the third day after crossover) | 
| Arterial blood K+ concentration | Arterial blood K+ concentration | On the 5th day after enrollment (On the 4th day after crossover) | 
| Arterial blood K+ concentration | Arterial blood K+ concentration | On the 6th day after enrollment (On the 5th day after crossover) | 
| Arterial blood K+ concentration | Arterial blood K+ concentration | On the 7th day after enrollment (On the 6th day after crossover) | 
| Arterial blood K+ concentration | Arterial blood K+ concentration | On the 8th day after enrollment (On the 7th day after crossover) | 
| Arterial blood K+ concentration | Arterial blood K+ concentration | On the 9th day after enrollment (On the 8th day after crossover) | 
| Arterial blood Ca2+ concentration | Arterial blood Ca2+ concentration | At the time of enrollment in the clinical study | 
| Arterial blood Ca2+ concentration | Arterial blood Ca2+ concentration | On the 24th hour after enrollment | 
| Arterial blood Ca2+ concentration | Arterial blood Ca2+ concentration | On the 48th hour after enrollment (On the 24th hour after crossover) | 
| Arterial blood Ca2+ concentration | Arterial blood Ca2+ concentration | On the third day after enrollment (On the 48th hour after crossover) | 
| Arterial blood Ca2+ concentration | Arterial blood Ca2+ concentration | On the 4th day after enrollment (On the third day after crossover) | 
| Arterial blood Ca2+ concentration | Arterial blood Ca2+ concentration | On the 5th day after enrollment (On the 4th day after crossover) | 
| Arterial blood Ca2+ concentration | Arterial blood Ca2+ concentration | On the 6th day after enrollment (On the 5th day after crossover) | 
| Arterial blood Ca2+ concentration | Arterial blood Ca2+ concentration | On the 7th day after enrollment (On the 6th day after crossover) | 
| Arterial blood Ca2+ concentration | Arterial blood Ca2+ concentration | On the 8th day after enrollment (On the 7th day after crossover) | 
| Arterial blood Ca2+ concentration | Arterial blood Ca2+ concentration | On the 9th day after enrollment (On the 8th day after crossover) | 
| Arterial blood Na+ concentration | Arterial blood Na+ concentration | At the time of enrollment in the clinical study | 
| Arterial blood Na+ concentration | Arterial blood Na+ concentration | On the 24th hour after enrollment | 
| Arterial blood Na+ concentration | Arterial blood Na+ concentration | On the 48th hour after enrollment (On the 24th hour after crossover) | 
| Arterial blood Na+ concentration | Arterial blood Na+ concentration | On the third day after enrollment (On the 48th hour after crossover) | 
| Arterial blood Na+ concentration | Arterial blood Na+ concentration | On the 4th day after enrollment (On the third day after crossover) | 
| Arterial blood Na+ concentration | Arterial blood Na+ concentration | On the 5th day after enrollment (On the 4th day after crossover) | 
| Arterial blood Na+ concentration | Arterial blood Na+ concentration | On the 6th day after enrollment (On the 5th day after crossover) | 
| Arterial blood Na+ concentration | Arterial blood Na+ concentration | On the 7th day after enrollment (On the 6th day after crossover) | 
| Arterial blood Na+ concentration | Arterial blood Na+ concentration | On the 8th day after enrollment (On the 7th day after crossover) | 
| Arterial blood Na+ concentration | Arterial blood Na+ concentration | On the 9th day after enrollment (On the 8th day after crossover) | 
| TCO2 | Total carbon dioxide in arterial blood | At the time of enrollment in the clinical study | 
| TCO2 | Total carbon dioxide in arterial blood | On the 24th hour after enrollment | 
| TCO2 | Total carbon dioxide in arterial blood | On the 48th hour after enrollment (On the 24th hour after crossover) | 
| TCO2 | Total carbon dioxide in arterial blood | On the third day after enrollment (On the 48th hour after crossover) | 
| TCO2 | Total carbon dioxide in arterial blood | On the 4th day after enrollment (On the third day after crossover) | 
| TCO2 | Total carbon dioxide in arterial blood | On the 5th day after enrollment (On the 4th day after crossover) | 
| TCO2 | Total carbon dioxide in arterial blood | On the 6th day after enrollment (On the 5th day after crossover) | 
| TCO2 | Total carbon dioxide in arterial blood | On the 7th day after enrollment (On the 6th day after crossover) | 
| TCO2 | Total carbon dioxide in arterial blood | On the 8th day after enrollment (On the 7th day after crossover) | 
| TCO2 | Total carbon dioxide in arterial blood | On the 9th day after enrollment (On the 8th day after crossover) | 
| HCT | hematocrit in arterial blood | At the time of enrollment in the clinical study | 
| HCT | hematocrit in arterial blood | On the 24th hour after enrollment | 
| HCT | hematocrit in arterial blood | On the 48th hour after enrollment (On the 24th hour after crossover) | 
| HCT | hematocrit in arterial blood | On the third day after enrollment (On the 48th hour after crossover) | 
| HCT | hematocrit in arterial blood | On the 4th day after enrollment (On the third day after crossover) | 
| HCT | hematocrit in arterial blood | On the 5th day after enrollment (On the 4th day after crossover) | 
| HCT | hematocrit in arterial blood | On the 6th day after enrollment (On the 5th day after crossover) | 
| HCT | hematocrit in arterial blood | On the 7th day after enrollment (On the 6th day after crossover) | 
| HCT | hematocrit in arterial blood | On the 8th day after enrollment (On the 7th day after crossover) | 
| HCT | hematocrit in arterial blood | On the 9th day after enrollment (On the 8th day after crossover) | 
| tHbc | Total hemoglobin in arterial blood | At the time of enrollment in the clinical study | 
| tHbc | Total hemoglobin in arterial blood | On the 24th hour after enrollment | 
| tHbc | Total hemoglobin in arterial blood | On the 48th hour after enrollment (On the 24th hour after crossover) | 
| tHbc | Total hemoglobin in arterial blood | On the third day after enrollment (On the 48th hour after crossover) | 
| tHbc | Total hemoglobin in arterial blood | On the 4th day after enrollment (On the third day after crossover) | 
| tHbc | Total hemoglobin in arterial blood | On the 5th day after enrollment (On the 4th day after crossover) | 
| tHbc | Total hemoglobin in arterial blood | On the 6th day after enrollment (On the 5th day after crossover) | 
| tHbc | Total hemoglobin in arterial blood | On the 7th day after enrollment (On the 6th day after crossover) | 
| tHbc | Total hemoglobin in arterial blood | On the 8th day after enrollment (On the 7th day after crossover) | 
| tHbc | Total hemoglobin in arterial blood | On the 9th day after enrollment (On the 8th day after crossover) | 
| height | m | At the time of enrollment in the clinical study | 
| Weight | Kg | At the time of enrollment in the clinical study | 
| gender | Male and female | At the time of enrollment in the clinical study | 
| age | year | At the time of enrollment in the clinical study | 
| WBC | The number of white blood cells in venous blood | On the first day after enrollment | 
| WBC | The number of white blood cells in venous blood | up to 9 days | 
| NEU | The number of Neutrophil granulocyte in venous blood | On the first day after enrollment | 
| NEU | The number of Neutrophil granulocyte in venous blood | up to 9 days | 
| LYM | The number of Venous blood lymphocytes in venous blood | On the first day after enrollment | 
| LYM | The number of Venous blood lymphocytes in venous blood | up to 9 days | 
| EOS | The number of Venous blood eosinophils in venous blood | On the first day after enrollment | 
| EOS | The number of Venous blood eosinophils in venous blood | up to 9 days | 
| BAS | The number of Venous blood Basophils in venous blood | On the first day after enrollment | 
| BAS | The number of Venous blood Basophils in venous blood | up to 9 days | 
| MON | The number of Venous blood Monocyte cell in venous blood | On the first day after enrollment | 
| MON | The number of Venous blood Monocyte cell in venous blood | up to 9 days | 
| RBC | The number of red blood cells in venous blood | On the first day after enrollment | 
| RBC | The number of red blood cells in venous blood | up to 9 days | 
| HGB | The number of haemoglobin in venous blood | On the first day after enrollment | 
| HGB | The number of haemoglobin in venous blood | up to 9 days | 
| HCT | hematocrit in venous blood | On the first day after enrollment | 
| HCT | hematocrit in venous blood | up to 9 days | 
| MCV | Mean Corpuscular Volume in venous blood | On the first day after enrollment | 
| MCV | Mean Corpuscular Volume in venous blood | up to 9 days | 
| MCH | Mean Corpuscular Haemoglobin Concentration in venous blood | On the first day after enrollment | 
| MCH | Mean Corpuscular Haemoglobin Concentration in venous blood | up to 9 days | 
| RDW | red blood cell distribution width in venous blood | On the first day after enrollment | 
| RDW | red blood cell distribution width in venous blood | up to 9 days | 
| PLT | platelet in venous blood | On the first day after enrollment | 
| PLT | platelet in venous blood | up to 9 days | 
| PDW | Platelet distributionwidth in venous blood | On the first day after enrollment | 
| PDW | Platelet distributionwidth in venous blood | up to 9 days | 
| MPV | Mean Platelet Volume in venous blood | On the first day after enrollment | 
| MPV | Mean Platelet Volume in venous blood | up to 9 days | 
| plateletcrit | plateletcrit in venous blood | On the first day after enrollment | 
| plateletcrit | plateletcrit in venous blood | up to 9 days | 
| CRP | C-reactive protein in venous blood | On the first day after enrollment | 
| CRP | C-reactive protein in venous blood | up to 9 days | 
| PCT | Procalcitonin in venous blood | On the first day after enrollment | 
| PCT | Procalcitonin in venous blood | up to 9 days | 
| NT-proBNP | NT-proBNP in venous blood | On the first day after enrollment | 
| NT-proBNP | NT-proBNP in venous blood | up to 9 days | 
| ESR | erythrocytesedimentationrate in venous blood | On the first day after enrollment | 
| ESR | erythrocytesedimentationrate in venous blood | up to 9 days | 
| PT | prothrombin time in venous blood | On the first day after enrollment | 
| PT | prothrombin time in venous blood | up to 9 days | 
| APTT | activated partial thromboplastin time in venous blood | On the first day after enrollment | 
| APTT | activated partial thromboplastin time in venous blood | up to 9 days | 
| TT | Thrombin time in venous blood | On the first day after enrollment | 
| TT | Thrombin time in venous blood | up to 9 days | 
| D-Di | D-Dimer in venous blood | On the first day after enrollment | 
| D-Di | D-Dimer in venous blood | up to 9 days | 
| ALT | alanine transaminase in venous blood | On the first day after enrollment | 
| ALT | alanine transaminase in venous blood | up to 9 days | 
| AST | Aspartate Transaminase in venous blood | On the first day after enrollment | 
| AST | Aspartate Transaminase in venous blood | up to 9 days | 
| PA | Serum prealbumin in venous blood | On the first day after enrollment | 
| PA | Serum prealbumin in venous blood | up to 9 days | 
| TP | Total serum protein in venous blood | On the first day after enrollment | 
| TP | Total serum protein in venous blood | up to 9 days | 
| ALB | Albumin protein in venous blood | On the first day after enrollment | 
| ALB | Albumin protein in venous blood | up to 9 days | 
| GLB | Globulin globulin in venous blood | On the first day after enrollment | 
| GLB | Globulin globulin in venous blood | up to 9 days | 
| Cr | creatinine in venous blood | On the first day after enrollment | 
| Cr | creatinine in venous blood | up to 9 days | 
| BUN | Urea nitrogen in venous blood | On the first day after enrollment | 
| BUN | Urea nitrogen in venous blood | up to 9 days | 
| Cys-C | Cystatin C in venous blood | On the first day after enrollment | 
| Cys-C | Cystatin C in venous blood | up to 9 days | 
| eGFR | Estimate glomerular filtration rate in venous blood | On the first day after enrollment | 
| eGFR | Estimate glomerular filtration rate in venous blood | up to 9 days | 
| Respiratory support time | Daily respiratory support time after patients were enrolled in the clinical study，h/Day | during hospitalization, approximately 9 days | 
| Relief time for dyspnea | Remission time of dyspnea after intervention | during hospitalization, approximately 9 days | 
| Tracheal intubation | Yes or No | during hospitalization, approximately 9 days | 
| Stay in the ICU | Yes or No | during hospitalization, approximately 9 days | 
| Complications | Facial injury, flatulence，Gastroesophageal reflux，Dry throat, sore throat，pneumothorax，Eye irritation discomfort，Low blood pressure. | during hospitalization, approximately 9 days | 
| Outcome of disease | Get better, get worse, die | during hospitalization, approximately 9 days | 
| Total bilirubin | Serum total bilirubin in venous blood | On the first day after enrollment | 
| Total bilirubin | Serum total bilirubin in venous blood | up to 9 days | 
| DBIL | Direct bilirubin in venous blood | On the first day after enrollment | 
| DBIL | Direct bilirubin in venous blood | up to 9 days | 
| IBIL | Indirect bilirubin in venous blood | On the first day after enrollment | 
| IBIL | Indirect bilirubin in venous blood | up to 9 days | 
| Diaphragm mobility | The patient is lying in a flat position. The convex array probe is placed at the junction of the anterior axillary line, midclavicular line, and rib margin (bilaterally), with the probe mark facing outward and downward for measurement. | At the time of enrollment in the clinical study | 
| Diaphragm mobility | The patient is lying in a flat position. The convex array probe is placed at the junction of the anterior axillary line, midclavicular line, and rib margin (bilaterally), with the probe mark facing outward and downward for measurement. | On the 24th hour after enrollment | 
| Diaphragm mobility | The patient is lying in a flat position. The convex array probe is placed at the junction of the anterior axillary line, midclavicular line, and rib margin (bilaterally), with the probe mark facing outward and downward for measurement. | On the 48th hour after enrollment (On the 24th hour after crossover) | 
| Diaphragm mobility | The patient is lying in a flat position. The convex array probe is placed at the junction of the anterior axillary line, midclavicular line, and rib margin (bilaterally), with the probe mark facing outward and downward for measurement. | up to 9 days | 
| Diaphragm thickness | Includes end-inspiratory diaphragm thickness and end-expiratory diaphragm thickness；The patient is lying flat on the bed. A linear array probe is placed in the mid-axillary line or between the anterior and mid-axillary lines between the eighth and tenth ribs, and measurements are taken. | At the time of enrollment in the clinical study | 
| Diaphragm thickness | Includes end-inspiratory diaphragm thickness and end-expiratory diaphragm thickness；The patient is lying flat on the bed. A linear array probe is placed in the mid-axillary line or between the anterior and mid-axillary lines between the eighth and tenth ribs, and measurements are taken. | On the 24th hour after enrollment | 
| Diaphragm thickness | Includes end-inspiratory diaphragm thickness and end-expiratory diaphragm thickness；The patient is lying flat on the bed. A linear array probe is placed in the mid-axillary line or between the anterior and mid-axillary lines between the eighth and tenth ribs, and measurements are taken. | On the 48th hour after enrollment (On the 24th hour after crossover) | 
| Diaphragm thickness | Includes end-inspiratory diaphragm thickness and end-expiratory diaphragm thickness；The patient is lying flat on the bed. A linear array probe is placed in the mid-axillary line or between the anterior and mid-axillary lines between the eighth and tenth ribs, and measurements are taken. | up to 9 days | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Patient compliance to the treatment | Patients were managed for compliance with the treatment.Dependent judgment Complete dependence: patients actively cooperate with medical staff in treatment Partial dependence: in most cases, patients can cooperate with the treatment, and in a few cases, patients resist the treatment but receive treatment after being enlightened by the medical staff. Non-dependence: patients have strong resistance and resistance, so that they are unable to use ventilators or nasal high-flow humidification instruments. | during hospitalization, approximately 9 days | 
| Kolcaba Comfort Scale (GCQ) assessment assesses patient comfort | Kolcaba's General Comfort Questionnaire (GCQ) is composed of 28 items from 4 dimensions: physiological, psychological, spiritual, socio-cultural and environmental. The modification Scale adopts 1 to 4Likert Scale, with 1 indicating strongly disagree and 4 indicating strongly agree. In the negative question, 1 means strongly agree and 4 means strongly disagree. A higher score indicates more comfort. | during hospitalization, approximately 9 days | 
| Dyspnea rating scale | According to the degree of dyspnea and symptoms of the patient, the lowest score is 0, the highest score is 10. | during hospitalization, approximately 9 days | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Hypoxemia, High-flow nasal cannula, Mechanical ventilation