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

In Reply: Dr Laudi and colleagues note that 32% of patients in our series received inhaled nitric oxide before commencing ECMO for 2009 influenza A(H1N1)–related ARDS. As a case series, management of patients followed clinical practice rather than standardized care, and we did not collect data on nitric oxide dosage or use once ECMO was initiated. One of the notable features of the pandemic was the widespread distribution of patients to intensive care units (ICUs) in Australia and New Zealand, with many admissions to community hospitals, few of which are likely to have nitric oxide available. The meta-analysis¹ cited by Laudi et al concluded that “nitric oxide is associated with limited improvement in oxygenation in patients with [acute lung injury] or ARDS but confers no mortality benefit and may cause harm.” We are unaware of data indicating that nitric oxide is better than other rescue therapies, such as recruitment maneuvers, prone positioning, and inhaled prostacyclin, which were widely used in our patients. We are also unaware of strong clinical evidence to support an antiviral effect.