Ventilators for Nonintensivists. Reasonable Initial Ventilator Settings for Patients with Acute Respiratory Distress Syndrome

Video 1.

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Reasonable initial ventilator settings for patients with acute respiratory distress syndrome.

As coronavirus disease (COVID-19) has rapidly evolved into a pandemic, many physicians without prior critical care training are being called upon to help manage severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2)–infected patients who develop respiratory failure and require mechanical ventilation. This video is intended to provide a brief and simplified approach to mechanical ventilation for nonintensivists with an overview of recommended initial ventilator settings for patients with acute respiratory distress syndrome (ARDS). ARDS is defined as an acute insult resulting in bilateral pulmonary opacities, not fully explained by effusions, atelectasis, nodules, or heart failure, and hypoxemia defined as a Pa_O2 to Fi_O2 ratio <300. ARDS patients are frequently intubated in the setting of hypoxia, hypercarbia, or increased work of breathing. For acutely ill patients, the most commonly used mode is the assist control mode. The assist control mode requires the clinician to set the Fi_O2, positive end-expiratory pressure (PEEP), respiratory rate, breath type (most commonly either volume

control [VC] or pressure control [PC]), and either inspiratory time or flow rate. Whether the clinician uses VC or PC, it is important that the set tidal volume (Vt) in case of VC or the resulting Vt in case of PC is 4–8 ml/kg of predicted body weight. Reasonable initial settings are 100% Fi_O2, PEEP of ≥5 cm H₂O, respiratory rate of 20, and Vt or PC to achieve 6 ml/kg of predicted body weight. Reasonable inspiratory flow rates for patients on VC are 60–80 L/min in decelerating ramp flow pattern or 30–40 L/min in square wave flow pattern. Reasonable initial inspiratory time for PC is 0.6–1 second.