chapter  20
22 Pages

Role of Tidal Volume and PEEP in the Reduction of VILI

WithDavid N. Hager, Roy G. Brower

Acute lung injury and acute respiratory distress syndrome (ALI/ARDS)

are life-threatening disorders associated with severe impairments of respiratory gas exchange. Without mechanical ventilation (MV), many

patients with ALI/ARDS would die from hypoxemic and hypercarbic

respiratory failure. MV allows time for treatment of the underlying condi-

tions that cause ALI/ARDS, such as pneumonia and sepsis, and for natural

healing processes. However, MV can also cause ALI [ventilator-induced

lung injury (VILI)], which may delay or prevent recovery. Modifications

of traditional MV techniques can reduce VILI and improve the likelihood

of recovery. These modifications include the use of relatively small tidal volumes with low inspiratory pressures (volume-and-pressure limitation)

and relatively high levels of positive end-expiratory pressure (higher

PEEP). In this chapter, we review the traditional approach to MV, the

experimental data that motivated investigators to study lung-protective

modifications of the traditional approach, and the results of clinical studies

that compare different MV approaches.