Predictors of Non-invasive Ventilation Failure in Patients With Acute Cardiogenic Pulmonary Edema

Inclusion Criteria: * Presence of ACPE diagnosed based on SpO2 below 90% with \>5 L/ min oxygen via reservoir face mask * Acute respiratory distress as evidenced by severe dyspnea * Breathing frequency of \>30 breaths/min, and use of accessory respiratory muscles or paradoxical abdominal motion in association with tachycardia * Cardiac gallops, bilateral rales, and typical findings of congestion on chest radiography, without a history suggesting pulmonary aspiration or evidence of pneumonia. Exclusion Criteria: * Patients were excluded from the study if they were intubated before ICU admission, or required immediate intubation without prior NIV, or presented a respiratory or cardiac arrest * Severe hemodynamic instability (systolic arterial pressure \<70 mmHg despite adequate fluid repletion and use of vasoactive agents) or life-threatening ventricular arrhythmias. * Patients were also excluded if they were unresponsive, agitated, and unable to cooperate; or if they had any condition that precluded application of a face mask including upper airway obstruction * Recent oral or facial trauma or surgery * Recent gastric or esophageal surgery * Inability to clear respiratory secretions or high risk for aspiration. * In addition, patients were excluded if they had a "do not intubate" order or refused research authorization.