Farling Stewart, Klitzman Bruce, Vesel Travis P, Cheifetz Ira M, Straube Tobias L, Deshusses Marc A
Department of Civil & Environmental Engineering, Duke University, Durham, NC, USA.
Kenan Plastic Surgery Research Labs, Duke University School of Medicine, Durham, NC, USA.
Ann Biomed Eng. 2024 Mar;52(3):638-646. doi: 10.1007/s10439-023-03411-x. Epub 2023 Dec 7.
We demonstrate a methodology which both improves oxygen transport and reduces or eliminates bubble formation in a novel hyperbaric membrane oxygenator catheter model system. Angular oscillations were introduced to a bundle of hollow fiber membranes (HFMs) supplied with hyperbaric 100% oxygen at average gauge pressures up to 0.35 barg. Oscillating bundles enabled delivery of an oxygen flux of up to 400 mL min m in an aqueous solution, a doubling over a previous non-oscillating setup. Similarly, the addition of angular oscillations facilitated a five-fold reduction in pressure to achieve similar oxygen flux. The increased angular speed of oscillation improved flux, while the addition of angular micro-oscillation variations resulted in flux reductions of 7-20% compared to continuous macro-oscillation only, depending on mixing conditions. However, semi-quantitative visual observation demonstrated that angular oscillations reduced or eliminated the instance of oxygen bubble formation on the HFMs. The modeled mass transfer coefficients indicated a quasi linear relationship between rotational velocity and flux, suggesting that faster oscillation speeds could further improve oxygen mass transport allowing for HFM bundles to maintain high oxygen fluxes while eliminating bubble formation. This encourages further development of our compact oxygenating catheter that could be used intravascularly.
我们展示了一种方法,该方法在一种新型高压膜式氧合器导管模型系统中既能改善氧气传输,又能减少或消除气泡形成。将角振荡引入一束中空纤维膜(HFMs),这些中空纤维膜在高达0.35 barg的平均表压下供应高压100%氧气。振荡束能够在水溶液中输送高达400 mL min m的氧气通量,比之前的非振荡设置增加了一倍。同样,添加角振荡有助于将压力降低五倍以实现相似的氧气通量。增加的角振荡速度提高了通量,而添加角微振荡变化导致与仅连续宏观振荡相比通量降低7 - 20%,这取决于混合条件。然而,半定量视觉观察表明,角振荡减少或消除了HFMs上氧气气泡形成的情况。模拟的传质系数表明旋转速度与通量之间存在准线性关系,这表明更快的振荡速度可以进一步改善氧气质量传输,使HFM束在消除气泡形成的同时保持高氧气通量。这鼓励了我们可用于血管内的紧凑型氧合导管的进一步开发。