The time-controlled adaptive ventilation protocol: mechanistic approach to reducing ventilator-induced lung injury.

Airway pressure release ventilation (APRV) is a ventilator mode that has previously been considered a rescue mode, but has gained acceptance as a primary mode of ventilation. In clinical series and experimental animal models of extrapulmonary acute respiratory distress syndrome (ARDS), the early application of APRV was able to prevent the development of ARDS. Recent experimental evidence has suggested mechanisms by which APRV, using the time-controlled adaptive ventilation (TCAV) protocol, may reduce lung injury, including: 1) an improvement in alveolar recruitment and homogeneity; 2) reduction in alveolar and alveolar duct micro-strain and stress-risers; 3) reduction in alveolar tidal volumes; and 4) recruitment of the chest wall by combating increased intra-abdominal pressure. This review examines these studies and discusses our current understanding of the pleiotropic mechanisms by which TCAV protects the lung. APRV set according to the TCAV protocol has been misunderstood and this review serves to highlight the various protective physiological and mechanical effects it has on the lung, so that its clinical application may be broadened.
Competing Interests: Conflict of interest: M. Kollisch-Singule reports grants from NIH during the conduct of the study, and other funding from Dräger Medical Systems, Inc. and the Intensive Care On-line Network, Inc. (ICON), outside the submitted work. Conflict of interest: P. Andrews has presented and received honoraria and travel reimbursement at events sponsored by Dräger Medical outside of the submitted work. She is employed by the Intensive Care On-line Network (ICON). Conflict of interest: J. Satalin has nothing to disclose. Conflict of interest: L.A. Gatto reports being listed as co-inventor in U.S. Patent No. 5 977 091 issued to the Research Foundation of SUNY (no related funds or royalties). Conflict of interest: G.F. Nieman reports grants from Drager Medical, outside the submitted work. In addition, He has patents issued on the method of preventing acute lung injury, the method of treating sepsis-induced ARDS, the novel method of assessing alveolar inflation, the method of reducing blood loss associated with cardiopulmonary bypass, minimally invasive suction and treatment device (MIST), and apparatus system and method for assessing alveolar inflation issued. Conflict of interest: N.M. Habashi has presented and received honoraria and travel reimbursement at events sponsored by Dräger Medical outside of the submitted work. He holds patents in the area of mechanical ventilation and is the founder of the Intensive Care On-line Network (ICON).
(Copyright ©ERS 2019.)