Figure 2. Experimental records that help illustrate the effects of the different ventilatory settings in a representative patient. From top to bottom: flow, airway opening pressure (Pao), volume (Delta V), esophageal, gastric, and transdiaphragmatic (Pdi) pressures. CPAP = continuous positive airway pressure; FA = flow assistance; PEEP = positive end-expiratory pressure; SB = spontaneous breathing; VA = volume assistance. Arrows indicate “runaway” breaths. See text for explanation.