Fig. 1.
Atelectasis 20 min after anesthesia and surgery during spontaneous breathing in patients with no positive end-expiratory pressure (PEEP) or continuous positive airway pressure (CPAP) during emergence and patients who had this support. Note the almost 50% smaller atelectasis when end-expiratory lung volume has been kept elevated by PEEP/CPAP. Reprinted with permission from Edmark et al.25