ID:133 FC-D01-4 High Oxygenation Efficiency in Femoro-Femoral V-V ECMO by Positioning the Tip of the Drainage Cannula in the Superior Vena Cava: A Case Report

Background: V-V ECMO in a femoro-femoral (F-F) configuration is often avoided due to concerns regarding recirculation. We previously reported that placing the drainage cannula tip in the superior vena cava (SVC) achieves high oxygenation in femoro-jugular configurations. Here, we applied this strategy to an F-F configuration. Clinical Course: A 65-year-old male with a history of lung cancer developed interstitial pneumonia caused by immune-related adverse events. Due to tumor invasion and limited venous access, an F-F configuration was selected. A 23Fr multistage drainage cannula was inserted via the right femoral vein with its tip in the SVC, and a 19Fr return cannula was placed via the left femoral vein with its tip near the fossa ovalis. Despite lung rest settings, a high PaO2 of 170.4 mmHg was initially achieved with a fraction of delivered oxygen (FDO2) of 1.0. Subsequently, FDO2 was weaned to 0.8 while maintaining a target PaO2 of 80 mmHg. Discussion: The high efficiency resulted from positioning the drainage cannula tip in the SVC, which enabled efficient blood drainage from both the SVC and IVC. This increased the proportion of oxygenated ECMO blood within the right atrium. While F-F configurations are generally associated with potential recirculation, this F(SVC)-F strategy provides excellent oxygenation efficiency. This suggests that the configuration may offers a margin to adjust the FDO2 levels as needed. Conclusion: Optimal oxygenation was achieved in an F-F configuration by positioning the drainage cannula tip in the SVC. This case suggests that this strategy may improve oxygenation efficiency when jugular access is limited.