Extracorporeal Membrane Oxygenation for ARDS Due to 2009 Influenza A(H1N1)

To the Editor: Dr Davies and colleagues¹ reported the use of extracorporeal membrane oxygenation (ECMO) for severe acute respiratory distress syndrome (ARDS) during the 2009 influenza A(H1N1) epidemic in Australia and New Zealand. Compared with the previous winter, the incidence of ECMO use was far greater in conjunction with H1N1 infections.

Only 20 patients (32%) were treated with inhaled nitric oxide before initiation of ECMO, although this therapy is considered an effective rescue treatment of refractory hypoxemia in acute lung injury.² Moreover, it is not reported whether inhaled nitric oxide was continued on ECMO and what concentrations were used. In addition to providing selective pulmonary vasodilation, inhaled nitric oxide may be an effective topical anti-infective agent,³ with activity against the replication of influenza viruses in vitro.⁴ During the severe acute respiratory syndrome (SARS) epidemic, an antiviral effect on the SARS coronavirus was reported.⁵ It remains to be determined whether inhaled nitric oxide might be a therapy for H1N1-induced acute respiratory failure that could reduce the need for and the duration of ECMO treatment.