Effects on PaCO2 Levels of Two Different Nasal Cannula in COPD Patients

Study Overview
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Brief Summary
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High-flow nasal cannula (HFNC) therapy is increasingly used in the management of acute respiratory failure. Its clinical application has been expanded also in other specific settings In stable COPD patients and in those recovering from acute exacerbation, HFNC can reduce PaCO2, respiratory rate, minute ventilation and respiratory effort. The aim of this randomized crossover physiological study is to investigate the effects on PaCO2 levels of two different nasal cannula ('Optiflow + Duet' interface vs standard nasal interface) in COPD patients with persistent hypercapnia following an acute severe exacerbation

Official Title
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Effects on PaCO2 Levels of Two Different Nasal Cannula in COPD Patients With Persistent Hypercapnia Following an Acute Severe Exacerbation

Conditions
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Chronic Obstructive Pulmonary Disease

Intervention / Treatment
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* Device: AIRVO 2, with conventional symmetric nasal cannula
* Device: AIRVO 2, the new asymmetric nasal cannula


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Inpatients recovering from an acute exacerbation of their disease Persisting hypercapnia, despite having reached a stabilization in pH (i.e. pH>7,35 and PaCO2>50 mmHg on 3 consecutive measurements) Informed consent Exclusion Criteria: Body Mass Index (BMI) > 30 kg/m2; Previous diagnosis of Obstructive sleep apnea syndrome (OSAS) Chest wall disease Heart failure Severe hemodynamic instability ( need for amine support) Acute coronary syndrome (ACS) Severe arrhythmia Renal insufficiency Patients unable to protect respiratory airways Respiratory arrest and need for endotracheal intubation Pregnancy Need for sedation Home long-term oxygen therapy

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: Crossover Assignment
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Active Comparator: HFNC 30 L/min with conventional symmetric nasal cannula<br>The patients will be asked to breathe with HFNC at flow of 30 L/min with standard interface | Device: AIRVO 2, the new asymmetric nasal cannula<br>* The patients will be asked to breathe with HFNC at flow of 30 L/min with the new asymmetric nasal cannula The size of nasal cannula will be selected to occlude patient's nostril of about 2/3. Temperature will be set according to the patient's tolerance starting from 31°C, up to 37°C, while FiO2 is adjusted to maintain SpO2 between 91 and 94%.<br>* Other names: Optiflow+ Duet;|
| Active Comparator: HFNC 30 L/min with new asymmetric nasal cannula<br>The patients will be asked to breathe with HFNC at flow of 30 L/min with the new asymmetric nasal cannula | Device: AIRVO 2, with conventional symmetric nasal cannula<br>* The patients will be asked to breathe with HFNC at flow of 30 L/min with the standard cannula The size of nasal cannula will be selected to occlude patient's nostril of about 2/3. Temperature will be set according to the patient's tolerance starting from 31°C, up to 37°C, while FiO2 is adjusted to maintain SpO2 between 91 and 94%.<br>* Other names: standard cannula;|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Changes of the partial pressure of carbon dioxide (PaCO2) levels | Arterial Blood Gases will be analyzed from a sample taken from the arterial artery | immediately after intervention | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Respiratory Rate ( RR), (b/min) | This parameter will be measured by a bioelectrical impedance monitor and a single-use Pad Set sensor that will be placed on the surface of the chest wall (ExSpiron, Respiratory Motion) Inc. USA) | 90 minutes | 
| Tidal Volume ( TV), (mL) | This parameter will be measured by a bioelectrical impedance monitor and a single-use Pad Set sensor that will be placed on the surface of the chest wall (ExSpiron, Respiratory Motion) Inc. USA) | 90 minutes | 
| Minute Ventilation (VE), (L/min) | This parameter will be measured by a bioelectrical impedance monitor and a single-use Pad Set sensor that will be placed on the surface of the chest wall (ExSpiron, Respiratory Motion) Inc. USA) | 90 minutes | 
| Inspiratory effort quantification | Esophageal pressure assessment through dedicated esophageal pressure transducer ( (Marquat Genie Biomedical,France) | 90 minutes | 
| Transcutaneous carbon dioxide (TcPCO2) and oxygen saturation (SpO2) | TcPCO2 and SpO2 will be recorded by using a dedicated device (SenTec AG, Therwil, Switzerland) | 90 minutes | 
| Dyspnea score | Dyspnea will be recorded using the Borg scale that is a numeric scale where 0 is no dyspnea and 10 the maximal dyspnea that a patient can imagine | immediately after intervention | 
| Comfort | this will be assessed by using the Visual Numerical Scale ranging between 1 (extreme discomfort) and 5 (very comfortable), | immediately after intervention | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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HFNC, Hypercapnia, COPD