Airway Pressure Release Ventilation (PC-APRV) enables spontaneous breathing under continuous positive airway pressure with brief pressure releases. With PC-APRV you could maximize the benefits of spontaneous breathing and stabilize and maintain the end expiratory lung volume.

It’s a pressure controlled ventilation mode where it’s possible to set two different levels of pressure (Phigh and Plow) and two different timings for the two pressure levels (Thigh and Tlow). In PC-APRV, the patient’s spontaneous breathing takes place at the upper pressure level Phigh. This pressure level Phigh is maintained for the duration of Thigh. The alternation between the two pressure levels is machine-triggered and time cycled. The breathing volume expired during the release times, results from the pressure difference between Phigh and Plow and the lung mechanics. Since resistance and/or compliance may change during the ventilation treatment, the supplied tidal volume and thus the minute volume also vary.

When the underlying pulmonary condition is restrictive and hypoxic in nature, fewer and shorter releases should be scheduled to avoid de-recruitment and maintain end-expiratory lung volume. When hypercapnia is an issue, more and longer releases will be required to assure sufficient ventilation.

APRV has been shown to facilitate spontaneous breathing and is associated with decreased peak airway pressures and improved oxygenation/ventilation when compared with conventional ventilation. Additionally, improvements in hemodynamic parameters, splanchnic perfusion, and reduced sedation/neuromuscular blocker requirements have been reported. APRV may offer potential clinical advantages for ventilator management of acute lung injury/acute respiratory distress syndrome and may be considered as an alternative “open lung approach” to mechanical ventilation.

In patients suffering from moderate to severe ARDS, application of APRV improved lung function and hemodynamics. It also reduced the need for sedatives and the duration of mechanical ventilation as well as days in ICU.⁴

1.   Putensen C., Zech S. et al. "Long-term effects of spontaneous breathing  during ventilatory support in patients with acute lung injury", American Journal of Critica Care Medicine 2001; 164; 43-49.
2.  Kollish-Singule, M. Emr, B. et al. "APRV reduces conducing airway micro-strain in lung injury", Journal of American College of Surgeons 2014, 219.9.
3.  Summeet et al. "The 30-year evolution of Airway Pressure Release Ventilation (APRV), Intensive Care Med Exp. 2016, 4:11. Published online 2016 May 20.
4.  Li JQ. Et al. "Clinical research about airway pressure release ventilation for moderate to severe acute respiratory distress syndrome", Eur Rev Med Pharmacol Sci. 2016 Jun; 20(12):2634-41