From the Guidelines
For patients with acute respiratory distress syndrome (ARDS), I recommend a lung-protective ventilation strategy with low tidal volumes of 4-6 mL/kg of predicted body weight and plateau pressures maintained below 30 cmH2O, as supported by the most recent guidelines 1.
Ventilator Settings
The initial settings should include a PEEP of 8-12 cmH2O, titrated based on oxygenation response, and an FiO2 starting at 100% that can be decreased as tolerated to maintain SpO2 between 88-95% 1.
- Respiratory rate should be set at 20-35 breaths per minute to achieve adequate minute ventilation while avoiding auto-PEEP.
- For severe ARDS cases with persistent hypoxemia (PaO2/FiO2 < 150), consider prone positioning for 12-16 hours daily, as this has shown a significant survival benefit for 28-day mortality 1.
Additional Considerations
- Recruitment maneuvers and possibly neuromuscular blockade with cisatracurium (initial bolus of 0.2 mg/kg followed by infusion of 1-2 mcg/kg/min) for the first 48 hours may also be considered for severe ARDS cases.
- Regular arterial blood gas monitoring is essential to guide adjustments, and daily assessment for readiness to wean ventilation should be performed once the patient stabilizes.
Rationale
These lung-protective strategies help prevent ventilator-induced lung injury by minimizing alveolar overdistension and cyclical opening and closing of alveoli, which can worsen inflammation and lung damage 1.
From the Research
Ventilator Settings for ARDS
The appropriate ventilator settings for a patient with Acute Respiratory Distress Syndrome (ARDS) include:
- Lung-protective ventilator strategies to minimize ventilator-induced lung injury 2, 3, 4
- Tidal volume (V(T)) of 6 mL/kg 2, 3
- Plateau pressure < 30 cmH2O 3
- Positive end-expiratory pressure (PEEP) set to maximize alveolar recruitment while avoiding overdistention 2, 3, 5
- Fraction of inspired oxygen (Fio(2)) and PEEP titrated to maintain arterial oxygen saturation (Spo(2)) of 88 to 95% (Pao(2) 55-80 mm Hg) 2, 3
- Respiratory rate of 20 to 35 breaths per minute 3
Advanced Modes of Ventilation
There is currently no clear proven benefit for advanced modes of ventilation in ARDS patients 2. However, assisted ventilation modes such as neurally adjusted ventilatory assist (NAVA) may improve patient-ventilator interaction and preserve respiratory variability 6.
Individualized Ventilator Settings
Bedside techniques have been developed to adapt ventilatory settings to the individual patient and the different stages of ARDS 4. The optimal ventilatory strategy may depend on the severity of ARDS, with higher PEEP recommended for moderate and severe ARDS 2, 5.