1. In a second part of the study mentioned above, Richard, et al4 also studied the effect of increasing PEEP relative to the measured LIP (LIP + 4 cm H2O, no SI) compared to PEEP set at the lower inflection point following SI. In 10 adults ventilated with low-tidal volume ventilation, measured lung volumes were 175±108 at PEEPLIP versus 332±91 ml at PEEPLIP+4. This increase was even more notable in patients ventilated with high tidal volumes (10 mL/kg), demonstrating the role of plateau pressures (in addition to PEEP) in alveolar recruitment (see Figure 3).