Background: Respiratory failure and acute respiratory distress syndrome secondary to H1N1 influenza infection is a source of substantial morbidity and mortality, having caused over 265,000 hospitalizations in the United States in 2009. During the H1N1 pandemic, up to 31% of the H1N1 patients required intensive care unit admission, and many were refractory to maximal conventional therapies. These most critically ill patients may require extracorporeal membrane oxygenation (ECMO) for survival.
Methods: We retrospectively reviewed the medical records of the 7 patients with refractory hypoxemia due to H1N1 influenza who were treated with ECMO in our pediatric intensive care unit.
Results: Five of the 7 patients survived to hospital discharge. The cohort's mean age was 21 years, and 4 were female. At admission to the pediatric intensive care unit, 6 had at least one comorbid condition, 6 were mechanically ventilated, and one was in shock. All 7 patients were treated with oral oseltamivir, high-frequency oscillatory ventilation, and inhaled nitric oxide prior to ECMO. Five received intravenous steroids, and 2 were treated with compassionate-use intravenous zanamivir. The mean duration of pre-ECMO ventilation was 8.7 days (range 14 h to 25 d). Mean oxygenation index was 50 (range 26-73) at ECMO cannulation. Six received venovenous ECMO, and one received venoarterial ECMO. The mean duration of ECMO was 432 hours (range 192-890 h).
Conclusions: This series suggests that ECMO is a viable treatment for refractory hypoxemia secondary to H1N1 influenza infection in both pediatric and adult patients.