Department of Transfusion Medicine, Tokyo Metropolitan Bokutoh Hospital, Tokyo, Japan.
Clinical Laboratory, Tokyo Metropolitan Bokutoh Hospital, Tokyo, Japan.
Blood Transfus. 2018 Feb;16(2):173-177. doi: 10.2450/2017.0231-16. Epub 2017 Mar 1.
Although ammonia in plasma does not usually pass through the blood-brain barrier (BBB), in cases of traumatic brain injury it may do so, acting as a neurotoxin on the brain. Excess intake of ammonia should be restricted in conditions involving BBB breakdown, such as traumatic brain injury. Washing is a method to remove ammonia from blood products, but fresh-frozen plasma and albumin products cannot be washed. A potassium adsorption filter (PAF) can remove not only potassium, but also ammonia from red blood cell solutions. We, therefore, examined the effects of a PAF on the removal of ammonia from a range of blood products.
Ammonia concentrations were measured in expired red blood cell solutions, fresh-frozen plasma, and platelet concentrates and purchased albumin products before and after filtration through a PAF. The PAF was primed with saline, which was removed before the filter was used.
The percentages of ammonia removal from the red blood cell solutions, fresh-frozen plasma, plasma concentrates, 20% albumin and 5% albumin were approximately 76-87%, 21-31%, 53%, 77-92% and 49-63%, respectively.
A PAF appears capable of removing ammonia from a range of blood products, although the reason for the lesser effect on the ammonia concentration in fresh-frozen plasma compared to other blood products remains unknown. We hypothesise that, by lowering ammonia levels in blood products, the PAF could improve the clinical prognosis of neonates with an underdeveloped BBB or patients with BBB breakdown following traumatic brain injury.
尽管血浆中的氨通常不会穿透血脑屏障（BBB），但在创伤性脑损伤的情况下，它可能会穿透并对大脑产生神经毒性。在涉及 BBB 破裂的情况下，如创伤性脑损伤，应限制氨的过度摄入。洗涤是一种从血液制品中去除氨的方法，但新鲜冷冻血浆和白蛋白制品不能洗涤。钾吸附过滤器（PAF）不仅可以去除钾，还可以从红细胞溶液中去除氨。因此，我们检查了 PAF 对各种血液制品中氨去除的影响。
在通过 PAF 过滤前后，测量了呼出的红细胞溶液、新鲜冷冻血浆和血小板浓缩物以及购买的白蛋白制品中的氨浓度。PAF 用生理盐水预充，在使用过滤器之前将其去除。
红细胞溶液、新鲜冷冻血浆、血浆浓缩物、20%白蛋白和 5%白蛋白中氨的去除率分别约为 76-87%、21-31%、53%、77-92%和 49-63%。
PAF 似乎能够从各种血液制品中去除氨，尽管与其他血液制品相比，其对新鲜冷冻血浆中氨浓度的影响较小的原因尚不清楚。我们假设，通过降低血液制品中的氨水平，PAF 可以改善未成熟 BBB 的新生儿或创伤性脑损伤后 BBB 破裂患者的临床预后。
