Gas exchange in extracorporeal circuits for neonates: comparison of three different canulation systems during animal...

During twenty animal experiments the effectiveness of the gas exchange during extracorporeal membrane oxygenation (ECMO) was evaluated. Arteriovenous, venovenous and venoarterial perfusion systems were compared. While PO2 saturation values were sufficient in all three groups the PO2 values were significant higher during arteriovenous perfusion (84.22 +/- 3.5 mmHg) compared to venovenous 71.99 +/- 7.3 mmHg) and venoarterial (65.11 +/- 4.5 mmHg) perfusion (p less than 0.001). PCO2 values correlated with the flow in the extracorporeal circuit in all three groups. The absolute values of PCO2 were significantly lowest during venoarterial perfusion (39.68 +/- 3.1 mmHg) compared to the venovenous (42.69 +/- 3.3 mmHg) and the arteriovenous mode (49.96 +/- 4.1 mmHg). These results indicate that perfusion circuits other than the original venoarterial ECMO could provide sufficient gas transfer for respiratory insufficient neonates while avoiding points of criticism of such systems.