High-frequency percussive ventilation in cardiac surgery patients failing mechanical conventional ventilation

Failure of mechanical conventional ventilation (MCV) after cardiac surgery portends a dismal prognosis, with extracorporeal membrane oxygenation frequently utilized as a salvage therapy. We describe our experience with high-frequency percussive ventilation (HFPV) as a rescue therapy for hypoxaemia refractory to MCV after cardiac surgery.

In a 6-year retrospective analysis from 2009 to 2015, we identified 16 subjects who required HFPV after cardiac surgery. Data regarding demographics, intraoperative details, postoperative ventilatory settings including length of time on HFPV and postoperative outcomes were collected. The primary outcome was improvement in oxygenation as measured by pre- and post-HFPV partial pressures of oxygen (pO2) and ratio of pO2 to fraction of inspired oxygen (P/F ratio).

Sixteen patients required HFPV after cardiac surgery. Operative procedures included coronary artery bypass surgery (n = 6), aortic aneurysm or dissection repair (n = 5), valve with bypass surgery (n = 2), aortic valve replacement (n = 2) and extracorporeal membrane oxygenation (n = 1). Median pO2 increased from 61 to 149.5 mmHg (P < 0.001) and the median P/F ratio improved from 62 to 169 (P < 0.001). The improvement in pO2 and P/F ratio was durable at 24 h whether the patient was returned to MCV (n = 4) or remained on HFPV (n = 12) with pO2 and P/F ratio increasing from 61 to 104 mmHg (P < 0.001) and from 62 to 193.5 (P < 0.001), respectively. Survival to discharge was 81%.

In our cohort of cardiac surgical patients, HFPV was successfully utilized as a rescue therapy, obviating the need for extracorporeal membrane oxygenation. Although further studies are warranted, HFPV should be considered in cardiac surgical patients failing MCV.