Airway pressure release ventilation (APRV) is another mode of ventilation that has been used in potential lung donor patients to improve hypoxemia or to limit PIP.35,36 It applies a high airway pressure (Phigh) over a prolonged inspiratory time with brief pressure releases to a low airway pressure (Plow), causing progressive lung recruitment and enhancing oxygenation.35,37 In transitioning from more conventional ventilator modes to APRV, the initial settings in adult lung donor patients usually consist of a Phigh (lasting 4-6 s) that is equivalent to the plateau airway pressure from the prior VCV or the previous PIP on PCV and a Plow of 0 cm H2O (lasting 0.2-0.8 s).35,37 A major benefit associated with APRV is lost in potential lung donor patients. In a patient who is not brain dead, APRV allows spontaneous breathing, thereby theoretically allowing better recruitment of dorsal dependent lung regions. However, in patients who are brain dead, this theoretical benefit does not exist.37 Thus, in this setting, it functions like pressure-controlled inverse ratio ventilation. A retrospective case series compared VCV to APRV in potential lung donor patients.36 Initial settings on VCV were 10 to 12 breaths/min, Vt of 5 to 10 mL/kg, Fio2 of 0.4, and PEEP of 5 cm H2O, whereas on APRV they were 6 to 10 breaths/min, Phigh of 20 to 25 cm H2O, and Fio2 of 0.4.36 However, the Vt generated, the presence or absence of auto-PEEP, and the duration of both Phigh and Plow (ie, prolonged inspiratory time and inspiratory time for the low CPAP level) were not reported. Nonetheless, patients on APRV had a higher mean Pao2/Fio2 (498 ± 43 mm Hg vs 334 ± 104 mm Hg) following a 45-min 100% oxygen challenge, which the authors attributed to improved alveolar recruitment and resolution of pulmonary atelectasis. They further suggest that this improvement in oxygenation may have led to concurrent rise in the rate of lung donation (95% vs 18%) in organ donors meeting standard criteria, with posttransplant survivals in both ventilator groups comparing favorably with national averages.36 This study, however, is limited by its retrospective nature as well as unreported ventilator data, which may have played a role in improving oxygenation.