Reduced Microstrain and Improved Alveolar Recruitment Using APRV

Ventilator-induced lung injury (VILI) exacerbates acute lung injury by causing additional atelectrauma and volutrauma at the microanatomical level. Kollisch-Singule and colleagues designed a randomized, nonblinded laboratory animal study to investigate alveolar microstrain of subpleural alveoli during dynamic inflation and deflation. The authors hypothesized that airway pressure release ventilation (APRV), with a prolonged plateau pressure (Phigh) and minimal time at end-expiratory release pressure (Plow), would minimize microstrain.

The authors found that an APRV termination of peak expiratory flow rate to peak expiratory flow rate ratio of 75% resulted in significantly less alveolar microstrain and improved alveolar recruitment. The methodology established in this study will likely prove useful in future large animal and clinical studies designed to investigate the optimal mechanical breath profiles for the prevention of VILI.

Read the full Concise Critical Appraisal by logging into the SCCM eCommunity. Concise Critical Appraisal is a regular feature aimed at highlighting the best and most relevant literature from a variety of academic journals and encouraging discussion around recent studies and research.

eNewsletter Issue: