Steel reinforced composite silicone membranes and its integration to microfluidic oxygenators for high performance gas exchange
Steel reinforced composite silicone membranes and its integration to microfluidic oxygenators for high performance gas exchange
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DOI：
10.1063/1.5014028
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发表时间：
2018-01-01
期刊：
影响因子：
3.2
通讯作者：
Selvaganapathy, P. Ravi
中科院分区：
文献类型：
--
作者：
Matharoo, Harpreet;Dabaghi, Mohammadhossein;Selvaganapathy, P. Ravi
呼吸窘迫综合征（RDS）是新生儿尤其是低出生体重儿的主要致死原因之一。在新生儿重症监护病房，已将市售体外氧合器用于低出生体重新生儿。然而，这些氧合器需要高血量来预充。在过去的十年中，已经为此目的开发了使用富氧的微流体氧合器。这些氧合器中的一些使用薄的聚二甲基硅氧烷（PDMS）膜以促进在微通道中流动的血液与外部环境空气之间的气体交换。然而，PDMS是弹性的，并且薄膜在压力下表现出显著的变形和分层，这改变了装置的结构，导致氧合不良或装置失效。因此，需要具有高稳定性、在压力下低变形和高气体交换的替代膜。在本文中，我们提出了一种新型的复合膜，由超薄不锈钢网嵌入PDMS，专为微流控单氧合器单元（SOU）设计。与均相PDMS膜相比，该复合膜表现出高稳定性、在压力下低变形和高气体交换。此外，引入了具有倾斜轮廓和锥形入口配置的氧合器的新设计，以在较低的压降下实现相同的气体交换。通过牛血测试SOU以评价气体交换性能。在所有测试的SOU中，具有复合膜的扁平设计SOU具有最高的氧交换，为40.32 ml/min m（2）。通过构建具有10 ml低预充体积的肺辅助装置（LAD），证明了具有复合膜的新装置的上级性能。在8 - 48 ml/min的血流速率下，通过0.48-0.90 ml/min的氧摄取和1.05-2.27 ml/min的CO2释放来实现LAD。该LAD显示在29 mm Hg的低压降下将氧饱和度水平增加25%。最后，用小猪在体测试LAD的气体交换能力。动物实验结果与体外结果一致，表明LAD能够在类似于24 ml/min的血液流速下提供充分的气体交换。
Respiratory distress syndrome (RDS) is one of the main causes of fatality in newborn infants, particularly in neonates with low birth-weight. Commercial extracorporeal oxygenators have been used for low-birth-weight neonates in neonatal intensive care units. However, these oxygenators require high blood volumes to prime. In the last decade, microfluidics oxygenators using enriched oxygen have been developed for this purpose. Some of these oxygenators use thin polydimethylsiloxane (PDMS) membranes to facilitate gas exchange between the blood flowing in the microchannels and the ambient air outside. However, PDMS is elastic and the thin membranes exhibit significant deformation and delamination under pressure which alters the architecture of the devices causing poor oxygenation or device failure. Therefore, an alternate membrane with high stability, low deformation under pressure, and high gas exchange was desired. In this paper, we present a novel composite membrane consisting of an ultra-thin stainless-steel mesh embedded in PDMS, designed specifically for a microfluidic single oxygenator unit (SOU). In comparison to homogeneous PDMS membranes, this composite membrane demonstrated high stability, low deformation under pressure, and high gas exchange. In addition, a new design for oxygenator with sloping profile and tapered inlet configuration has been introduced to achieve the same gas exchange at lower pressure drops. SOUs were tested by bovine blood to evaluate gas exchange properties. Among all tested SOUs, the flat design SOU with composite membrane has the highest oxygen exchange of 40.32 ml/min m(2). The superior performance of the new device with composite membrane was demonstrated by constructing a lung assist device (LAD) with a low priming volume of 10 ml. The LAD was achieved by the oxygen uptake of 0.48-0.90 ml/min and the CO2 release of 1.05-2.27 ml/min at blood flow rates ranging between 8 and 48 ml/min. This LAD was shown to increase the oxygen saturation level by 25% at the low pressure drop of 29 mm Hg. Finally, a piglet was used to test the gas exchange capacity of the LAD in vivo. The animal experiment results were in accordance with in-vitro results, which shows that the LAD is capable of providing sufficient gas exchange at a blood flow rate of similar to 24 ml/min. Published by AIP Publishing.