Table 2

Equations for calculating pulmonary mechanics in ventilated patients

Static compliance

Tidal volume/(P_plat - PEEP)

Total lung resistance

(P_peak - P_plat)/flow

Airways resistance

(P_peak - P_init)/flow

Viscoelastic resistance

(P_init - P_plat)/flow

Flow, inspiratory flow rate; PEEP, positive end-expiratory pressure; P_init = initial pressure; P_peak = peak airway pressure; P_plat = plateau pressure.

Jain and Sznajder Critical Care 2007 11:206   doi:10.1186/cc5159