四联袋及配套的塑料卡在制作成分血过程中，塑料卡的功能是将曲折后的多联袋导管卡住，以避免保养液、添加剂、血液串袋。但经过离心，常常出现塑料卡使血袋壁变薄、破裂，造成破袋漏血而使血液报废。为避免这种情况的发生，笔者采用橡皮圈代替塑料卡的办法，即将多联袋导... The function of the plastic card is to trap the tortuous multiple-bundle catheters in order to avoid maintenance fluids, additives, and blood string bags. However, after centrifugation, plastic cards often appear to make the wall of the blood bag thinner and broken, causing the bag to leak blood and causing the blood to be scrapped. In order to avoid this happening, the author uses a rubber band instead of a plastic card method;