Effects of High-intensity Noninvasive Positive Pressure Ventilation in AECOPD

Study Overview
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Brief Summary
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This study aims to investigate the effects of high-intensity noninvasive positive pressure ventilation (NPPV), as compared with low-intensity NPPV, on hypercapnia, consciousness, inspiratory muscle effort, dyspnea, NPPV tolerance, inflammatory response, adverse events and other outcomes in patients with acute exacerbation of chronic obstructive pulmonary disease.

Official Title
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Effects of High-intensity Versus Low-intensity Noninvasive Positive Pressure Ventilation in Acute Exacerbation of Chronic Obstructive Pulmonary Disease: A Randomized Controlled Trial

Conditions
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Acute Exacerbation of Chronic Obstructive Pulmonary Disease

Intervention / Treatment
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* Device: High-intensity NPPV
* Device: Low-intensity NPPV


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Diagnosis of COPD according to the criteria of the Global Initiative for Chronic Obstructive Lung Disease in 2019 Presence of acute exacerbation Arterial pH <7.35 with arterial carbon dioxide tension (PaCO2) >45 mmHg on room air or supplemental oxygen PaCO2 >45 mmHg following low-intensity NPPV of ≥6 hours Exclusion Criteria: Age <18 years Excessive amount of respiratory secretions or weak cough Upper airway obstruction Recent oral, facial, or cranial trauma or surgery; recent gastric or esophageal surgery Potential risk factors for restrictive ventilatory dysfunction (eg, consolidation or removal of at least one pulmonary lobe, massive pleural effusion, chest wall deformity, continuous strapping with thoracic or abdominal bandage, and severe abdominal distention) Active upper gastrointestinal bleeding Cardiac or respiratory arrest Arterial oxygen tension/fraction of inspired oxygen <100 mmHg Pneumothorax Severe ventricular arrhythmia or myocardial ischemia Severe hemodynamic instability despite fluid repletion and use of vasoactive agents Severe metabolic acidosis Refusal to receive NPPV Endotracheal intubation already performed before ICU admission

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: High-intensity NPPV<br>The patients will receive high-intensity noninvasive positive pressure ventilation. | Device: High-intensity NPPV<br>* In the high-intensity NPPV group, patients will undergo pressure-limited NPPV (eg, NPPV in spontaneous/timed mode) at a higher IPAP level. IPAP is initially set at 10 cmH2O and continuously adjusted by increments and decrements of 1-2 cmH2O (typically ranging between 20 and 30 cmH2O), according to patients' tolerance, to obtain a tidal volume (VT) of 10-15 mL/kg. IPAP should be increased as much as possible to decrease PaCO2 to a normal level. However, if PaCO2 decreases to less than 35 mmHg, IPAP should be decreased to achieve normocapnia.<br>|
| Active Comparator: Low-intensity NPPV<br>The patients will receive low-intensity noninvasive positive pressure ventilation. | Device: Low-intensity NPPV<br>* In the low-intensity NPPV group, patients will undergo pressure-limited NPPV (eg, NPPV in spontaneous/timed mode) with a conventional IPAP level. IPAP is initially set to 10 cmH2O and is continuously adjusted by increments and decrements of 1-2 cmH2O (up to 20 cmH2O), according to patients' tolerance, to obtain a VT of 6-10 mL/kg.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| PaCO2 measured at 24 hours after enrollment | PaCO2 measured at 24 hours after enrollment. | 24 hours | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| PaCO2 measured at 2 hours after enrollment | PaCO2 measured at 2 hours after enrollment | 2 hours | 
| PaCO2 measured at 6 hours after enrollment | PaCO2 measured at 6 hours after enrollment | 6 hours | 
| PaCO2 measured at 48 hours after enrollment | PaCO2 measured at 48 hours after enrollment | 48 hours | 
| PaCO2 measured at 72 hours after enrollment | PaCO2 measured at 72 hours after enrollment | 72 hours | 
| Glasgow coma scale score | The glasgow coma scale score, ranging from 3 (coma) to 15 (normal consciousness), will be used to assess the consciousness level. | 72 hours | 
| ΔPes | Inspiratory esophageal pressure swing | 72 hours | 
| Dyspnea score | The dyspnea score will be assessed using a verbal analogue scale with levels from 0 (no dyspnea) to 10 (maximum dyspnea). | 72 hours | 
| NPPV tolerance score | NPPV tolerance will be recorded on a 4-point scale and then dichotomized into acceptable (score of 2 or 3) or poor (score of 0 or 1) tolerance. | 72 hours | 
| Plasma level of TNF-α | Plasma level of TNF-α | 72 hours | 
| Plasma level of I-1β | Plasma level of IL-1β | 72 hours | 
| Plasma level of IL-6 | Plasma level of IL-6 | 72 hours | 
| Plasma level of IL-8 | Plasma level of IL-8 | 72 hours | 
| Plasma level of IL-10 | Plasma level of IL-10 | 72 hours |