High Hemoglobin Level As a Limiting Factor for Extracorporeal Membrane Oxygenation.

We report the case of a 47 year old male who developed acute respiratory distress syndrome after bariatric surgery, requiring a venovenous extracorporeal membrane oxygenation. An inadequate extracorporeal membrane oxygenation output flow was observed, possibly because of severe polycythemia and hyperviscosity. Management with acute normovolemic hemodilution corrected both the biologic and hemodynamic parameters. To our knowledge, this is the first reported case of acute normovolemic hemodilution to improve extracorporeal membrane oxygenation outflow. Clinicians should be aware that polycythemia and hyperviscosity may impair extracorporeal membrane oxygenation support and that acute normovolemic hemodilution may be a safe and efficient procedure to address such matter. The optimal hemoglobin level on extracorporeal membrane oxygenation deserves further investigation.