A-Maze-Ox: a novel gas-exchange-area-adjustable oxygenator for extremely preterm infants—design and proof of concept

Background Each year, over half a million children worldwide are born extremely prematurely (EPI), often requiring potentially harmful ventilatory support. An artificial placenta with gas exchange provided by an oxygenator offers an alternative. However, current oxygenators are not designed for long-term applications in patients experiencing growth. Thus, a new type of “growing” oxygenator is needed. Methods We developed the A-Maze-Ox, a novel maze-inspired membrane oxygenator featuring two concentric compartments that can be opened sequentially to address patient growth. Each compartment has a priming volume of 5 mL and a gas exchange area of 0.065 m². The prototype was tested for feasibility, gas transfer performance and pressure loss according to ISO 7199. Results Adding the second compartment increased O 2 and CO 2 transfer performance by 57.06% and 35.59%, respectively. While CO 2 transfer was mostly sufficient, O 2 transfer remained below the target. The targeted maximum pressure drop of 20 mmHg was exceeded at 90 mL/min. Conclusions The A-Maze-Ox demonstrates the ability to adapt to increasing demands with good results in CO 2 elimination but requires improvement in terms of O 2 transfer and pressure drop. However, it shows the potential for a growing oxygenator in future artificial placenta applications. Impact Current oxygenators cannot adapt to the dynamic patient growth of extremely premature infants. A-Maze-Ox—a novel membrane oxygenator with two compartments can adapt to growth. Each compartment has a volume of 5 mL and a gas exchange area of 0.065 m². Oxygen transfer increased by 57.06% and carbon dioxide transfer by 35.59% when adding the second compartment. A-Maze-Ox could improve health of extremely premature infants in the future.