In total, 6,419 patients qualified for inclusion. Of these, inhaled nitric oxide was used among 3,629 patients during extracorporeal membrane oxygenation run. Approximately one half of the study patients received inhaled nitric oxide at extracorporeal membrane oxygenation initiation. The proportion of patients receiving inhaled nitric oxide during extracorporeal membrane oxygenation decreased with increasing duration of extracorporeal membrane oxygenation