Functional Cardiovascular Engineering Laboratory, University of California San Diego, La Jolla, California, United States.
J Appl Physiol (1985). 2024 Jan 1;136(1):213-223. doi: 10.1152/japplphysiol.00397.2023. Epub 2023 Dec 7.
High-molecular-weight linear polymers (HMWLPs) have earned the name "drag-reducing polymers" because of their ability to reduce drag in turbulent flows. Recently, these polymers have become popular in bioengineering applications. This study investigated whether the addition of HMWLP in a venoarterial extracorporeal circulation (ECC) model could improve microvascular perfusion and oxygenation. Golden Syrian hamsters were instrumented with a dorsal skinfold window chamber and subjected to ECC using a circuit comprised of a peristaltic pump and a bubble trap. The circuit was primed with lactated Ringer solution (LR) containing either 5 ppm of polyethylene glycol (PEG) with a low molecular weight of 500 kDa (PEG500k) or 5 ppm of PEG with a high molecular weight of 3,500 kDa (PEG3500k). After 90 min of ECC at 15% of the animal's cardiac output, the results showed that the addition of PEG3500k to LR improved microvascular blood flow in arterioles and venules acutely (2 h after ECC), whereas functional capillary density showed improvement up to 24 h after ECC. Similarly, PEG3500k improved venular hemoglobin O saturation on the following day after ECC. The serum and various excised organs all displayed reduced inflammation with the addition of PEG3500k, and several of these organs also had a reduction in markers of damage with the HMWLPs compared to LR alone. These promising results suggest that the addition of small amounts of PEG3500k can help mitigate the loss of microcirculatory function and reduce the inflammatory response from ECC procedures. High-molecular-weight linear polymers have gained traction in bioengineering applications. The addition of PEG3500k to lactated Ringer solution (LR) improved microvascular blood flow in arterioles and venules acutely after extracorporeal circulation (ECC) in a hamster model and improved functional capillary density up to 24 h after ECC. PEG3500k improved venular hemoglobin O saturation and oxygen delivery acutely after ECC and reduced inflammation in various organs compared to LR alone.
高分子线性聚合物（HMWLP）因其能够减少湍流中的阻力而被称为“减阻聚合物”。最近，这些聚合物在生物工程应用中变得流行。本研究探讨了在静脉-动脉体外循环（ECC）模型中添加 HMWLP 是否可以改善微血管灌注和氧合。金黄地鼠被安置了一个背部皮肤窗室，并使用由蠕动泵和气泡阱组成的回路进行 ECC。该回路用含有 5ppm 低分子量 500kDa 的聚乙二醇（PEG500k）或 5ppm 高分子量 3500kDa 的 PEG（PEG3500k）的乳酸林格溶液（LR）预充。在 15%动物心输出量的 ECC 90 分钟后，结果表明，LR 中添加 PEG3500k 可急性改善微动脉和微静脉中的微血管血流（ECC 后 2 小时），而功能毛细血管密度在 ECC 后 24 小时内持续改善。同样，ECC 后第二天，PEG3500k 也改善了微静脉的血红蛋白 O 饱和度。与单独使用 LR 相比，添加 PEG3500k 可减少血清和各种切除器官的炎症，并且这些器官中的几种也减少了与 HMWLP 相关的损伤标志物。这些有希望的结果表明，添加少量 PEG3500k 可以帮助减轻微循环功能的丧失，并减少 ECC 过程中的炎症反应。高分子线性聚合物在生物工程应用中得到了广泛关注。在金黄地鼠模型的 ECC 后，将 PEG3500k 添加到乳酸林格溶液（LR）中可急性改善微动脉和微静脉中的血流，并在 ECC 后 24 小时内改善功能毛细血管密度。PEG3500k 可改善 ECC 后微静脉的血红蛋白 O 饱和度和氧输送，并与单独使用 LR 相比，减少各种器官的炎症。
