Figure 5

Measurement of end-inspiratory plateau pressure, an estimate of average end-inspiratory alveolar pressures. The peak-to-plateau gradient is easily determined by stopping flow at end-inspiration and can be used as a measure of the severity of inspiratory airway resistance. The plateau pressure is a reflection of the respiratory system pressure change resulting from the delivery of the tidal volume, added to any level of intrinsic positive end-expiratory pressure. The plateau pressure is a useful marker of lung hyperinflation and should be maintained at less than 30 cmH₂O. The dotted line indicates a high peak-to-plateau gradient observed in status asthmaticus. Published with permission from Principles of Critical Care [69].