Volume-targeted Versus Pressure-limited Noninvasive Ventilation in Patients With Acute Hypercapnic Respiratory Failure

Study Overview
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Brief Summary
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Volume-targeted noninvasive ventilation (VT-NIV), a hybrid mode that targets a preseted tidal volume (VT) by automated adjustment of pressure support, could guarantee the delivered VT over pressure-limited noninvasive ventilation (PL-NIV) with fixed level pressure support. Whether VT-NIV is more effective in improving gas exchange in patients with acute hypercapnic respiratory failure (AHRF) as compared with PL-NIV remains unclear. Our aim was to verify whether in comparison with PL-NIV, use of VT-NIV was more effective in correcting hypercapnia, hence reducing the need for intubation and improving survival in patients with AHRF.

Conditions
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Acute Hypercapnic Respiratory Failure

Intervention / Treatment
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* Device: Volume-targeted noninvasive ventilation


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: acute hypercapnic respiratory failure (AHRF) arterial pH <7.35 and ≥7.25 PaCO2 >45 mmHg 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 severe metabolic acidosis; severe abdominal distension cardiac or respiratory arrest PaO2/FiO2 <150 mmHg pneumothorax severe ventricular arrhythmia or myocardial ischemia severe hemodynamic instability despite fluid repletion and use of vasoactive agents active upper gastrointestinal bleeding lack of cooperation refusal to receive NIV

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: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Volume-targeted noninvasive ventilation<br>For Volume-targeted noninvasive ventilation, the target VT was set at 10 ml/kg of ideal body weight, with inspiratory positive airway pressure (IPAP) ranging from 10 cmH2O up to 25 cmH2O. | Device: Volume-targeted noninvasive ventilation<br> <br> |
| No Intervention: Pressure-limited noninvasive ventilation<br>For Pressure-limited noninvasive ventilation, IPAP was initially set at 10 cmH2O, and was adjusted by increments of 1-2 cmH2O according to patients' tolerance (up to 25 cmH2O) to obtain a VT of 8-10 ml/kg of ideal body weight and a respiratory rate (RR) less than 25 breaths/min. | |

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| The decrease of arterial partial pressure of carbon dioxide (PaCO2) values from baseline to 6 hours after randomization | PaCO2 value at baseline minus PaCO2 value at 6 hours after randomization | 6 hours after randomization |