Three‐dimensional membranes for artificial lungs: Comparison of flow‐induced hemolysis

• Published in: Artificial organs Vol. 46; no. 3; pp. 412 - 426
• Main Authors: Hesselmann, Felix, Arnemann, Daniel, Bongartz, Patrick, Wessling, Matthias, Cornelissen, Christian, Schmitz‐Rode, Thomas, Steinseifer, Ulrich, Jansen, Sebastian Victor, Arens, Jutta
• Format: Journal Article
• Language: English
• Published: United States Wiley Subscription Services, Inc 01-03-2022
• Subjects: artificial lung; Artificial Organs; Boundary layers; Design; Equipment Design; Hemolysis; Hollow fiber membranes; Humans; in vitro test; Laminar boundary layer; Lung; Lungs; Mass transport; Membranes; Membranes, Artificial; Minimal surfaces; Oxygen; Oxygen transfer; pressure loss; Printing, Three-Dimensional; three‐dimensional membrane; TPMS; three-dimensional membrane; artificial lung; in vitro test; TPMS; pressure loss; hemolysis
• ISSN: 0160-564X; 1525-1594
• DOI: 10.1111/aor.14081

Background
Membranes based on triply periodic minimal surfaces (TPMS) have proven a superior gas transfer compared to the contemporary hollow fiber membrane (HFM) design in artificial lungs. The improved oxygen transfer is attributed to disrupting the laminar boundary layer adjacent to the membrane surface known as main limiting factor to mass transport. However, it requires experimental proof that this improvement is not at the expense of greater damage to the blood. Hence, the aim of this work is a valid statement regarding the structure‐dependent hemolytic behavior of TPMS structures compared to the current HFM design.
Methods
Hemolysis tests were performed on structure samples of three different kind of TPMS‐based designs (Schwarz‐P, Schwarz‐D and Schoen’s Gyroid) in direct comparison to a hollow fiber structure as reference.
Results
The results of this study suggest that the difference in hemolysis between TPMS membranes compared to HFMs is small although slightly increased for the TPMS membranes. There is no significant difference between the TPMS structures and the hollow fiber design. Nevertheless, the ratio between the achieved additional oxygen transfer and the additional hemolysis favors the TPMS‐based membrane shapes.
Conclusion
TPMS‐shaped membranes offer a safe way to improve gas transfer in artificial lungs.
The hemolysis induced by different structures (TPMS) with better oxygen transfer properties were investigated in comparison to the state‐of‐the‐art hollow fiber design. The difference in hemolysis between TPMS membranes compared to hollow fiber membranes is small compared to the improved oxygen transfer provided by 3D‐Membranes.