Ventilator Settings for Mechanically Ventilated Patients
Initial Ventilator Settings
- The American Thoracic Society recommends starting with lung-protective ventilation using tidal volumes of 4-8 ml/kg predicted body weight, plateau pressure ≤30 cmH2O, PEEP ≥5 cmH2O, initial FiO2 of 40%, and respiratory rate 20-35 breaths/min 1
- For most patients, start with tidal volume of 6-8 ml/kg predicted body weight 1, 2
- For patients with ARDS, use tidal volume of 4-6 ml/kg predicted body weight 1, 2
Disease-Specific Modifications
- For ARDS patients, maintain plateau pressure <30 cmH2O and apply higher PEEP (≥10 cmH2O) for moderate-severe ARDS 1, 4
- For obstructive disease patients, use tidal volume of 6-8 ml/kg predicted body weight and set I:E ratio 1:2 to 1:4 to prevent air-trapping 3, 4
- For cardiac patients, apply the same principles as for non-cardiac patients and use sufficient PEEP to maintain end-expiratory lung volume 3
Ventilator Mode Selection
- No specific mode is universally superior, but consider pressure-controlled ventilation and volume-controlled ventilation 2, 5, 6, 7
Critical Monitoring Parameters
- Obtain arterial blood gas within 1-2 hours of initiating mechanical ventilation and monitor dynamic compliance and driving pressure (plateau pressure - PEEP) 2, 3
- Assess for auto-PEEP, especially in obstructive disease, and monitor pressure-time and flow-time scalars 3