VentilationHigh-frequency oscillatory ventilation with and without arteriovenous extracorporeal lung assist in patients with severe respiratory failure

PurposeElimination of carbon dioxide by an arteriovenous extracorporeal lung assist (av-ECLA) can facilitate the lung protective capabilities of high-frequency oscillatory ventilation (HFOV). This case series describes patients treated with HFOV because of severe respiratory failure with and without additional av-ECLA.MethodsA retrospective analysis of 31 patients regarding patient characteristics, gas exchange, respirator settings, hemodynamics, and outcome. In 18 patients, av-ECLA was started before, together with, or during HFOV.ResultsThe initial arterial carbon dioxide tension before HFOV and av-ECLA was higher in patients who received av-ECLA compared with patients without (P = .043): 65 (48-84) mm Hg and 50 (44-60) mmHg (median and interquartile range). The initial arterial oxygen tension (Pao2)/inspiratory oxygen fraction (Fio2) index in patients who received av-ECLA was 79 (63-133) mm Hg. The Pao2/Fio2 index immediately before HFOV was 84 (65-124) mm Hg (av-ECLA) and 121 (68-150) mmHg (no av-ECLA) and improved to 149 (89-231) mm Hg and 200 (117-233) mmHg during HFOV. Similarly, the oxygenation index improved. No statistically significant differences among groups were detected for Pao2/Fio2 index, oxygenation index, and arterial carbon dioxide tension immediately before and during HFOV. The hospital mortality was 39% (av-ECLA) and 69% (no av-ECLA).ConclusionsHigh-frequency oscillatory ventilation improved the oxygenation in patients with severe respiratory failure. Additional av-ECLA may facilitate using lung protective HFOV settings in more severe lung injury and hypercapnia.