The intravascular membrane oxygenator (IVOX) is placed into the vena cava via a catheter, without housing or perfusion device, and is anticipated to be used during transportation in ambulance and other emergency settings. For intravascular placement of the IVOX, there are some difficulties in ensuring efficient blood flow over the hollow fiber membrane, thus hampering adequate gas exchange. In this study, we sought to improve the gas exchange performance of the IVOX by introducing a blood flow induction conduit inside the hollow fiber membrane bundles. We designed the appropriate shape and placement of the conduit using computational fluid dynamics analysis. We then constructed a model based on the experimental design and evaluated the model in vitro to examine the oxygen and carbon dioxide transfer rates as well as pressure drop. Our results showed that the mean blood velocity in the hollow fiber membrane bundles was lower for the newly designed model than that for a conventional model without the induction conduit, and we confirmed an 80% improvement over the conventional model in terms of the volumes of oxygen and carbon dioxide flow at a blood flow of 3L/min.
