The Effects of Repetitive Alveolar Recruitment on Oxygenation and Compliance in ARDS patients

Abstract

Background If the effects of alveolar recruitment are beneficial, but of short duration, repetitive recruitment maneuvers (RMs) will be necessary to maintain oxygenation. This study was performed to assess the effect of repetitive alveolar recruitment, with high-sustained inflation pressure on oxygenation and compliance of the respiratory system, in patients with acute respiratory distress syndrome.

Methods Ten adult patients on ventilator support, with controlled mechanical ventilation, received three repetitive RMs with a high-sustained inflation pressure. The time intervals from the first to second RM and from the second to third RM were 8.42 ± 0.56 hours and 12.43 ± 1.45 hours, respectively. Recruitment was conducted by setting the ventilator mode to a continuous positive airway pressure of 40 cmH2O for 40 seconds. After each alveolar recruitment, the previous ventilator settings in the pressure control mode were re-established with a high positive end expiratory pressure. The FIO2, PaO2/FIO2 and lung compliance (tidal volume/[plateau pressure - PEEP]) were recorded with reference to the arterial blood gas analysis at both 30 minutes pre and post recruitment.

Results The FIO2 was able to be decreased from 0.9 to 0.5 while maintaining the PaO2 at higher than 80 mmHg after three recruitments. The PaO2/FIO2 improved from 98 to 288 and the compliance of the respiratory system improved from 26 to 41 ml/cmH2O after three recruitments.

Conclusions Our results suggest that repetitive recruitment can be used to maintain the beneficial effects of alveolar recruitment in patients with acute respiratory distress syndrome when supported using a lung protective mechanical ventilation strategy.