The effect of high-frequency oscillatory ventilation combined with tracheal gas insufflation on extravascular lung water in patients with acute respiratory distress syndrome: a randomized, crossover, physiologic study

Abstract

Purpose: High-frequency oscillation combined with tracheal gas insufflation (HFO-TGI) improves oxygenation in patients with acute respiratory distress syndrome (ARDS). There are limited physiologic data regarding the effects of HFO-TGI on hemodynamics and pulmonary edema during ARDS. The aim of this study was to investigate the effect of HFO-TGI on extravascular lung water (EVLW).

Materials and methods: We conducted a prospective, randomized, crossover study. Consecutive eligible patients with ARDS received sessions of conventional mechanical ventilation with recruitment maneuvers (RMs), followed by HFO-TGI with RMs, or vice versa. Each ventilatory technique was administered for 8 hours. The order of administration was randomly assigned. Arterial/central venous blood gas analysis and measurement of hemodynamic parameters and EVLW were performed at baseline and after each 8-hour period using the single-indicator thermodilution technique.

Results: Twelve patients received 32 sessions. Pao2/fraction of inspired oxygen and respiratory system compliance were higher (P<.001 for both), whereas extravascular lung water index to predicted body weight and oxygenation index were lower (P=.021 and .029, respectively) in HFO-TGI compared with conventional mechanical ventilation. There was a significant correlation between Pao2/fraction of inspired oxygen improvement and extravascular lung water index drop during HFO-TGI (Rs=-0.452, P=.009).

Conclusions: High-frequency oscillation combined with tracheal gas insufflation improves gas exchange and lung mechanics in ARDS and potentially attenuates EVLW accumulation.

Keywords: Acute respiratory distress syndrome; Extravascular lung water; High-frequency ventilation.