Efficacy and Safety of High-Flow Nasal Cannula Versus Noninvasive Ventilation for Pulmonary Arterial Hypertension-Associated Acute Respiratory Failure

HFNC treatment HFNC therapy. The initial flow rate of 50-60 L/min was subsequently adjusted to maintain an oxygen saturation (SpO2) ≥92%. The FiO2 was titrated to maintain the PaO2 between 60 and 80 mmHg.

NIV treatment A Mindray SV300 ventilator (Mindray Medical International Limited, Shenzhen, China) was used to deliver NIV via an oronasal mask. The initial inspiratory positive airway pressure (IPAP) was 12-15 cmH2O and adjusted later to achieve a tidal volume of 6-8 mL/kg of predicted body weight and a respiratory rate of \<30 breaths/min. The expiratory positive airway pressure (EPAP) was established at 5-8 cmH2O. Additional-ly, FiO2 was titrated to maintain a PaO2 between 60 and 80 mmHg.