血液储存条件对制备去白细胞血液的影响

目的：研究血液温度、储存时间对制备去白细胞全血的影响。方法：使用连接去白细胞滤器的多联袋采集CPD-抗凝全血,将其分为0 d冷藏组、0 d常温组、1 d冷藏组,分别过滤。测定过滤时间、白细胞去除率、残留白细胞数和红细胞回收率。结果：0 d冷藏组和0 d常温组相比,白细胞去除率明显提高。红细胞回收率略有下降,过滤时间延长,但差异均无显著性;0 d冷藏组和1 d冷藏组相比,白细胞去除率差异无显著性,但红细胞回收率显著提高。过滤时间延长,但差异无显著性。结论：血液温度对全血中白细胞滤除率的影响显著,延长冷藏时间未能产生影响。根据不同的滤器,必须确定其最佳过滤时间,确保白细胞的有效去除及血液的质量。     

4种一次性去白细胞滤器血袋的质量评价

目的评价3种国产和1种进口一次性去白细胞滤器血袋应用效果。方法随机抽取3种国产和1种进口一次性去白细胞滤器400 ml四联血袋在6 h内采集的血液各20袋进行白细胞过滤,检测过滤后的红细胞回收率、白细胞残留量、过滤前后的游离血红蛋白及凝血因子FⅧ∶C的生物学活性,记录血液过滤时间及有无堵塞现象。结果 1种国产滤器血袋红细胞回收率达不到85%国家标准;2种国产滤器血袋白细胞残留量检测达不到≤5.0×106/400 ml国家标准,进口滤器白细胞残留量可达≤1.0×106/400 ml欧洲标准,4种滤器血袋过滤白细胞前后FHb含量和FⅧ∶C生物活性变化无统计学意义,均符合国家标准;1种进口滤器血袋过滤时间明显高于国产滤器血袋,差异有统计学意义。结论其中1种国产滤器血袋和1种进口滤器血袋对6 h采集的血液进行白细胞过滤效果较好,可保证新鲜冰冻血浆制备需求。     

滤除白细胞对红细胞溶血的观察

目的:了解过滤白细胞造成红细胞溶血的程度。方法:取4℃保存第5天的40袋2U悬浮红细胞随机分为A、B两组,A组与白细胞滤器连接进行过滤,留取检测样品,分别于过滤后第0、7、14、21天分别采用离子选择电极法测定血浆中钾离子浓度、邻甲联苯胺法测定游离血红蛋白浓度。B组不做过滤处理,其他处理同A组。结果:去白细胞滤器滤过的血液中钾离子浓度、游离血红蛋白浓度随保存时间的延长而增高。结论:过滤后的红细胞悬液最好在7d内用完。     

血液温度、贮存时间对制备去白细胞全血的影响

【目的】探讨血液温度、贮存时间对制备去白细胞全血的影响。方法使用连接去白细胞滤器的多联血袋采集ACD-B抗凝全血,将其分为0d常温组、0d冷藏组和1d冷藏组3组,分别过滤。测定过滤时间、白细胞去除率、剩余白细胞数和红细胞回收率。结果0d冷藏组与0d室温组相比,白细胞去除率显著提高(P<0.05),红细胞回收率略有下降,过滤时间延长,但差异均无显著性;0d冷藏组与1d冷藏组相比,白细胞去除率的差异无显著性,但红细胞回收率显著提高(P<0.05),过滤时间延长,但差异无显著性。结论血液温度对全血中白细胞滤除的影响显著,增加冷藏时间未能产生进一步的影响。针对不同的滤器,必须确定其最适过滤条件,保证白细胞的有效去除和血液成分的质量。     

几种滤白全血四联袋的选用和质量评价

目的评价5种去白全血四联袋对采集的全血滤除白细胞的质量的影响。方法分别用5个厂家的滤白全血四联袋对全血进行过滤,观察滤白后红细胞回收率、血细胞比容（HCT）、白细胞残余量、白细胞清除率、游离血红蛋白含量等指标。结果 1～5组红细胞回收率均超过90%,符合大于或等于85%的要求,差异无统计学意义（P〉0.05）;HCT均大于0.35,差异无统计学意义（P〉0.05）;游离血红蛋白含量在111～114mg/L,低于300mg/L的要求,差异无统计学意义（P〉0.05）;白细胞清除率均超过99%,各组间差异无统计学意义（P〉0.05）。5个厂家的白细胞滤器过滤后白细胞残余量均符合小于或等于2.5×106/200mL的要求。1、4组进口滤器过滤白细胞后血液的白细胞残余量均比其他3组国产滤器低。5组滤器白细胞清除率均达到了99.9%,甚至1、4组进口滤器达到了99.99%,而且国产的3、5组也达到了99.98%,去白效果均令人满意。结论如果严格按厂家说明书要求的过滤时的温度和时间,国产滤器也能达到很好的去除白细胞的效果,而且成本较低。     

新型一次性去白细胞滤器血袋应用研究

目的评价一次性去白细胞滤器血袋的应用效果。方法采用CB-RFQM206CDF(1U)和CB-RFQM406CDF(2U)一次性去白细胞滤血袋,随机抽取采集7h内的新鲜全血60袋(各30袋),观察过滤时间、过滤前后细菌学检测、重量、游离血红蛋白含量以及血液常规指标等的变化;另取2种滤器血袋各5个批号各过滤5袋血液,比较不同批号滤器间白细胞过滤效果;采用细胞记数仪检测过滤前后血液常规指标,并用Nageotte计数板检测过滤后残留白细胞数、邻甲苯胺法检测FHb含量。结果2种滤器血袋过滤白细胞前后的血液均无细菌污染。CB-RFQM206CDF和CB-RFQM406CDF型滤器血袋血液过滤时间分别为(321.4±132.9)s和(663.3±210.5)s,血液回收率为(91.68±1.80)%和(92.70±2.11)%,白细胞去除率均为(99.998±0.001)%,白细胞残留量为(2.4±0.7)×104/袋和(4.6±1.6)×104/袋,红细胞回收率为(92.49±4.05)%和(91.99±3.28)%。2种滤器血袋过滤白细胞前后血液其它红细胞指标和FHb含量均无明显变化。2种滤器血袋不同批号间的白细胞去除率和红细胞回收率差异均无统计学意义(P>0.05)。结论该2种新型一次性去白细胞过滤血袋质量优良。     

两种制备去白细胞悬浮红细胞方法的比较

目的探索使用全血及悬浮红细胞过滤白细胞对血液质量的影响。方法使用带有软壳的白细胞滤器、ACDB方抗凝剂四联采血袋采集全血60袋,随机分为各30袋的甲、乙两组,采血后18-24h内过滤白细胞,甲组为全血过滤,乙组为悬浮红细胞过滤。白细胞过滤后24h内测定血红蛋白含量和白细胞残留量,于采血后第1周、第2周、第3周、第4周、储存期末测定红细胞溶血率。结果两组血红蛋白含量和白细胞残留量相比差异无统计学意义（P〉0.05）;两组血液储存第一周红细胞溶血率相比较无显著差异（P〉0.05）,而在第2周、第3周、第4周及储存期末红细胞溶血率差异有统计学意义（P〈0.05）,乙组红细胞溶血率显著增加。结论使用全血或悬浮红细胞过滤白细胞制备的去白细胞悬浮红细胞,血红蛋白含量及白细胞残留量均无差异,但是使用悬浮红细胞制备的去白细胞悬浮红细胞,在储存第2周之后红细胞溶血现象较为显著,所以在发往医疗机构时,应优先发出使用悬浮红细胞过滤白细胞制备的去白细胞悬浮红细胞。     

应用软芯滤器进行血液过滤的效果分析

目的探讨软芯滤器对白细胞的滤除效果。方法取200袋400 ml全血分为实验组（软芯滤器组）和对照组（硬芯滤器组）,于24 h内按操作规程滤除白细胞,计算两组的白细胞残留量、红细胞回收率及血浆游离血红蛋白含量等指标。将两组滤后血液成分各1 000袋应用于临床观察效果。结果两组在白细胞残留量、红细胞回收率及血浆游离血红蛋白含量等指标间的差异无统计学意义（P〉0.05）,在临床应用效果方面差异没有显著性。结论软芯滤器的各项指标符合相关标准,在使用过程中较硬芯滤器方便,值得推广应用。     

国产一次性去除白细胞采血袋的应用评价

为有效预防输血后同种免疫的发生和相关病毒的传播[1],笔者选择3种一次性去除白细胞四联袋,于采血后4~6h内过滤去除白细胞,检测白细胞去除率、红细胞回收率、红细胞压积(Hct)、血小板回收率和血浆游离血红蛋白,评价临床输注是否安全有效。1材料与方法1.1将3家厂家提供的四联一次性白细胞滤器分为Ⅰ、Ⅱ、Ⅲ组,15袋/组,滤前滤后采样检测,于采血后4~6h内滤除白细胞,严格按各滤器的说明书操作。1.2检测方法及计算公式滤前白细胞、血红蛋白及滤前滤后红细胞、Hct、血小板均采用全自动血细胞计数仪(美国Abbott)测定,滤后白细胞采用Nageotte计数…     

去白细胞悬浮红细胞的临床应用

目的观察去白细胞前后血液质量变化,及临床输注去白细胞悬浮红细胞降低非溶血性发热性输血反应（FNHTR）的效果。方法随机采集全血30袋（300ml/袋）,在滤除白细胞操作前、后分别留取血液样本进行检测,分别记录过滤前后血液指标。分析临床130例输注去白细胞悬浮红细胞患者和133例输悬浮红细胞患者FNHTR的发生率。结果过滤后红细胞（RBC）回收率大于90%、白细胞去除率99.99%、血小板去除率76.66%、过滤后血液容积减少（44.28±3.12）ml,血红蛋白（HGB）含量、红细胞压积Hct、游离血红蛋白含量FHb、MCV、MCH及MCHC过滤前后的差异无统计学意义（P〉0.05）。去白细胞组FNHTR发生率（2.95%）低于悬浮红细胞组（12.29%）,差异有统计学意义（P〈0.01）。结论国产一次性使用去白细胞滤器可有效去除白细胞,且红细胞回收率大于90%,达到或超过血站基本标准中对去白细胞血液成分的要求。临床输注去白细胞悬浮红细胞能有效减少非溶血性发热性输血反应的发生,提高输血质量。     

Leukodepletion filters reduce Leishmania in blood products when used at collection or at the bedside

BACKGROUND: Leishmania is an intracellular parasite of monocytes transmissible by transfusion. The feasibility of reducing Leishmania with leukodepletion filters was studied. At collection, infected blood contains the amastigote form of Leishmania within monocytes. Amastigotes cause the rupture of monocytes releasing free amastigotes that convert to promastigotes, which exist extracellularly at blood storage temperatures. Leukodepletion filters were tested at various time points in this process. STUDY DESIGN AND METHODS: Blood products were infected with Leishmania organisms and then filtered with whole-blood filters at collection, with bedside filters after storage, and to determine whether free promastigotes could be eliminated. RESULTS: Filtration at collection reduced Leishmania by 3 to 4 log or to the level of detection. Filtration of infected red cells after 2 weeks of storage showed a reduction of Leishmania by 4 log. Filtration resulted in a 6- to 8-log reduction in promastigotes either in the presence or in the absence of white cells within the filter. CONCLUSION: Filtration at the time of collection and after storage of Leishmania-infected blood resulted in a substantial reduction of free and intracellular organisms. There is currently no donor screen for Leishmania. Until adequate testing is developed, the use of leukodepletion filters could add to the safety of the blood supply.     

In vitro evaluation of platelet concentrates, prepared from pooled buffy coats, stored for 8 days after filtration

BACKGROUND: Posttransfusion complications can be prevented by pretransfusion removal of donor white cells from platelet concentrate. The filtration used for this removal seems to have little effect on platelet function and activation, but more information is needed on its effect on function during subsequent long-term storage of concentrate. STUDY DESIGN AND METHODS: The effect of prestorage filtration of buffy coat-prepared platelet concentrates (PCs) on platelet function, metabolism, and activation was investigated. A pool of three PCs, each made of four buffy coats, was split into three equal volumes; two were filtered over two different filters and the third served as a control. Variables monitored immediately after filtration and during the subsequent 8-day storage period at 22 degrees C included aggregation upon stimulation with collagen and/or ADP, platelet adhesion capacity to collagen and fibrinogen in flowing blood, nucleotide content of and nucleobase release by the platelets, expression of activation-dependent antigens, and beta-thromboglobulin release by the platelets. RESULTS: No differences were observed between the PCs filtered over two different filters and the nonfiltered control PCs immediately after filtration and during storage, except for a selective removal (20%) of beta-thromboglobulin by one filter. CONCLUSION: PCs prepared from a pool of four buffy coats can be filtered and subsequently stored for 8 days (starting +/− 24 hours after whole blood collection) without detriment to platelet function, metabolism, or activation.     

Leukoreduction filtration of whole-blood units from sickle trait donors: effects of a metered citrate anticoagulant system

BACKGROUND: Polymerization of hemoglobin (Hb) S is exacerbated by acidic and hyperosmotic citrate anticoagulant solutions and often results in occlusion of leukoreduction filters by red blood cells (RBCs) from sickle cell trait (Hb AS) donors. This study evaluates a blood collection instrument that adds citrate anticoagulant in a metered fashion, thus mitigating adverse citrate effects. STUDY DESIGN AND METHODS: Collection of whole blood by a metered anticoagulant system was compared to traditional phlebotomy in 12 Hb AS and 12 non-sickle trait (Hb AA) donors. Each donated twice; on one occasion, units were filtered after 4-hour storage at 20 to 24 degrees C, and on the other, units were stored at 1 to 6 degrees C for 24 hours before filtration. RESULTS: Filtration times, RBC recoveries, and residual white blood cell (WBC) counts met defined criteria more often in Hb AS units collected by a metered anticoagulant system (9 of 12, 8 of 12, and 4 of 12, respectively) compared to traditional phlebotomy (1 of 12, 2 of 12, and 0 of 12, respectively). Overall, Hb AS units filtered better after storage at 1 to 6 degrees C for 24 hours, with units collected by a metered anticoagulant system undergoing filtration most effectively (5 of 6 had >85% RBC recovery, 3 of 6 had <5 x 10(6) residual WBC). Units exhibited similar changes in RBC storage parameters. CONCLUSION: Use of a metered anticoagulation instrument demonstrates potential for successful leukoreduction and acceptable storage of Hb AS units; however, the system needs further modifications and improvements before it can be utilized to collect and leukoreduce Hb AS blood.     

保存前去除白细胞对浓缩红细胞保存质量影响研究

为了研究保存前去除白细胞对不同方法制备的浓缩红细胞 (RCC)保存质量的可能影响 ,分别取分离血浆后所得浓缩红细胞 (RCC1)和分离富含血小板血浆后所得含少量血浆的浓缩红细胞 (RCC2 )各 8袋 ,每袋等量分为两份 :过滤组和对照组。过滤组在保存当天用去白细胞滤器过滤 ,然后按常规方法 4℃保存 35天 ;对照组直接 4℃常规保存 5周。每周取样本测定平均红细胞体积 (MCV)、平均红细胞血红蛋白含量 (MCH)和平均红细胞血红蛋白浓度 (MCHC) ,血浆K+浓度和乳酸脱氢酶 (LDH) ,游离血红蛋白 (FHb)和红细胞ATP水平 ,同时做细菌培养污染监测。结果表明 :两种方法制备的RCC在过滤组与对照组中MCV ,MCH和MCHC无显著差别 ;红细胞ATP水平在保存第 0 ,1,2和 3周过滤组与对照组无显著差异 ,第 4和 5周过滤组红细胞ATP水平低于对照组 (P <0 .0 5 ) ;在保存过程中过滤组K+水平低于对照组 ,除了RCC1在保存第 0 ,1,2和 3周与对照组无显著差别外 ,均有显著差异 (P <0 .0 5 )。过滤组血浆LDH释放量显著低于对照组 (P <0 .0 1) ,在分离血小板后制备的RCC2这种差别更为明显。在保存期间RCC2组血浆的FHb水平过滤组显著低于对照组 (P <0 .0 5 ) ,而RCC1两组间FHb水平无显著差异。各组细菌培养均为无细菌生长。结论 :保存前去白细胞过     

Improved red cell quality after erythroplasmapheresis with MCS-3P

The cell separator MCS-3P is an apheresis system offering the flexibility to collect standardized red blood cells, plasma, and/or platelets from one donor. Two different programs were used for the red cell apheresis'RBCP (collection of one unit of red cells and two units of plasma) and RBCPS (one unit of red cells and one unit of plasma). The quality of the red cell concentrates (RCC resuspended in SAG-Mannitol) during the storage time of 42 days was measured by biochemical (ATP, 2,3-DPG, pH, free Hb, free potassium, glucose, lactose, p⁵⁰, hemoglobin derivatives) and Theological (morphological index, filtration/rigidity index) parameters. The donation time with 53 donors was 20 min for 355 ml RCC-SAGM and 440 ml plasma and 7 min for 335 ml RCC-SAGM and 239 ml plasma. The donor tolerance was analogous to plateletpheresis or plasmapheresis. Twenty units of the RCC-SAGM were in-line filtered within 6 or 24 hours after donation. The results obtained for red blood cell storage are at least as good as with standard collection (free hemoglobin, free potassium, glucose, lactose, hemolysis) or better (ATP, 2,3-DPG, p⁵⁰, hemoglobin derivatives, filtration/rigidity index) owing to prevention of collection lesion. All blood preparations were sterile after storage (red cells 42 days, plasma after freezing). The erythroplasmapheresis with MCS-3P can be especially recommended for application in an autologous blood program because the application of autologous blood donation in hospitals is often limited by the preconditions of component separation. The erythroplasmapheresis data with MCS-3P are encouraging for the development of a new blood collection methodology.     

The in vitro evaluation of two filters (Erypur and Imugard IG 500) for white cell-poor platelet concentrates

White cell-poor blood components are useful in patients with white cell antibodies. White cells are efficiently removed by two different filters, Imugard and Erypur, which have used saline as the filter solution. This study evaluated these filters as to their production of white cell-poor platelets. Pools of random-donor platelet concentrates were filtered. Prefiltration and postfiltration samples were evaluated for percentages of platelet recovery, white cell (WBC) removal, and platelet function. The two filter solutions tested were normal-strength saline (NSS) and fresh-frozen plasma (FFP). Postfiltration samples using NSS showed no measurable platelet aggregation with ADP, epinephrine, or collagen. However, with FFP, both filters showed 100 percent platelet aggregation with ADP, epinephrine, and collagen. The FFP filter solution provided excellent white cell removal in both filters (Imugard: 100% WBC removal or less than 1.0 X 10(6) residual WBC; Erypur: 99.5% removal or greater than 1.0 X 10(7) residual WBC); however, platelet recovery was better with Imugard (95%) than with Erypur (55%). The filtration procedure is an excellent method for the preparation of white cell-poor platelets; however, the quantity of the saline solution recommended for the filtering of red cells must be minimized for platelets.     

血液白细胞滤除方法及其临床应用效果比较

【目的】探讨去白细胞血液制备最佳工艺方法和临床应用效果。【方法】应用五种全血过滤方法,即无菌导管连接法（A法）;贮存后过滤法（B法）;采用血袋和滤器一体四联袋采血后6h直接过滤法（C法）;采用血袋和滤器一体四联袋采血后24～72h直接过滤法（D法）;采用血袋和滤器一体四联袋采血后96h直接过滤法（E法）。对过滤前后的血液进行血细胞计数、游离血红蛋白含量、红细胞膜脆性实验、白细胞介素2（IL-2）等质量检测,同时计算去白细胞血液红细胞回收率、白细胞去除率。比较不同方法制备的去白细胞血液经临床输注后红细胞输注效果及非溶血性发热性输血反应（febrilenonhemolytictransfusionreactions,FNHTR）。【结果】采用不同的过滤方法制备的血液产品质量不同,B法与C法制备血液临床输注后FNHTR和红细胞输注效果都有统计学意义（P〈0．05）。B法和E法两种方法与A法、C法、D法三种方法比较去白细胞血液红细胞脆性和游离血红蛋白FHb有统计学意义（P〈0．05）,同时前两种方法制备血液保存期末IL-2与其它方法也有差异（P〈0．01）。C法制备的去白细胞血液质量及制备工艺整体优于其它方法,而且能够减少临床FNHTR和红细胞输注无效。【结论】采用联袋采集血液后6h内进行血液白细胞过滤,能够提高临床输血整体疗效,减少红细胞输注无效及FNHTR。     

Prestorage white cell reduction in saline-adenine-glucose-mannitol red cells by use of an integral filter: evaluation of storage values and invivo recovery

BACKGROUND : Prestorage white cell (WBC) reduction in blood components may decrease the incidence of adverse reactions and improve component quality. A bottom-and-top system with an integral third-generation WBC- reduction filter has been studied. STUDY DESIGN AND METHODS : Whole blood was collected from 30 healthy donors: from 20 by using a blood container system with an integral filter and from 10 controls by using a standard blood container system. Ten test units were buffy coat- depleted, stored for 72 hours at 4 degrees C, and then filtered, while an additional 10 test units were buffy coat-depleted and filtered at room temperature within 8 hours of collection. All units were stored at 4 degrees C for 42 days and sampled weekly. RESULTS : The mean WBC content of the 72-hour, 4 degrees C units was 0.33 × 10(6), that of the room-temperature units was 2.6 × 10(6), and that of the buffy coat- depleted controls was 460 × 10(6) (p < 0.0005). No significant differences were found among lactate, glucose, sodium, potassium, and plasma hemoglobin levels in the three groups. ATP and 2,3 DPG levels were significantly better preserved in control units than in 72-hour, 4 degrees C units (p = 0.016 and p = 0.032, respectively), but not better than in the room-temperature units. Significant differences were observed between pH values in filtered units and both groups of test units (p = 0.016). In biologic terms however, these differences were small. Red cells from an additional eight healthy volunteer donors were processed by an 8-hour room-temperature method and stored for 35 days. Studies in vivo 24-hour recovery of autologous red cells were performed by transfusing a radiolabeled (51Cr plus 131I-albumin) aliquot after 35 days' storage. Good recovery (mean > 80%) was found by both the single- and double-isotope-label methods. Recovery was significantly greater when calculated by the single-isotope method (p = 0.02). CONCLUSION : The combination of buffy coat removal and filtration in the blood container system with an integral filter achieved effective WBC reduction (> or = 3 log10 reduction from whole blood) without biologically significant detriment to in vitro or in vivo storage values.     

Improved removal of white cells with minimal platelet loss by filtration of apheresis platelets during collection

BACKGROUND: Filtration of apheresis platelets to remove white cells (WBCs) requires operator intervention after the collection procedure (postcollection filtration), which may cause variable and unsatisfactory filter performance (WBC removal and platelet loss). The MCS+ LN9000 apheresis system filters platelets through a WBC-reduction filter during each collection cycle (continuous filtration) at a flow rate of 15 to 25 mL per minute. Apheresis platelets obtained by continuous filtration were evaluated in terms of platelet loss, WBC removal, and platelet storage properties and then were compared to unfiltered apheresis platelets and to apheresis platelets that underwent postcollection filtration. Two WBC-reduction filters were tested (LRF6 and LRFXL). STUDY DESIGN AND METHODS: In 70 apheresis platelets, postcollection filtration was performed by using the LRF6 at flow rates of 80 mL per minute (n = 30) and 50 mL per minute (n = 30) and the LRFXL at 50 mL per minute (n = 10). One hundred fifty-eight apheresis platelets underwent continuous filtration through the LRF6 (n = 58) or the LRFXL (n = 100). Unfiltered apheresis platelets (controls) (n = 30) were obtained by the same collection protocol. RESULTS: Estimated platelet loss with continuous filtration was 7 percent for the LRFXL and 3 percent for the LRF6. A reduction in the filtration flow rate from 80 to 50 mL per minute with postcollection filtration through the LRF6 resulted in markedly lower WBC levels, with 10 percent versus 57 percent of the apheresis platelets having WBC counts <1 × 10⁵, respectively. Additional improvements in WBC removal were found with continuous filtration; 85 percent of the apheresis platelets filtered with the LRF6 and 100 percent of the apheresis platelets filtered with the LRFXL had WBC counts <1 × 10⁵. CONCLUSIONS: Continuous or postcollection filtration of freshly collected apheresis platelets resulted in minimal platelet loss. Better WBC removal from apheresis platelets was obtained with continuous filtration than with postcollection filtration, likely because of the slower flow rate. Platelet storage quality was not affected by filtration.     

In-line filtration of autologous whole blood

BACKGROUND: Experimental data suggest that autologous white blood cells (WBCs) might exert an immunomodulatory effect. Leukodepletion of autologous blood is considered to prevent this unwanted side effect of autologous transfusion. In some cases, however, prolonged filtration or filtration failures occur. Because such autologous units cannot simply be discarded, the interest was in the storage variables of autologous whole blood (AWB) units after prolonged filtration. STUDY DESIGN AND METHODS: AWB of patients undergoing orthopedic surgery was leukodepleted before storage or left unmodified. Filtration times, volume, WBC count, hemoglobin level, hemolysis, potassium, and ATP were determined in all units with filtration times of more than 60 minutes that had not been transfused by the time of expiry and in representative samples of units that had been filtered normally or that had not been filtered. RESULTS: In AWB filtration, the rate of prolonged filtrations or filter blockades is three to four times higher than in allogeneic whole-blood filtration. Filtration or prolonged filtration leads to a mean loss of red blood cell (RBC) mass of 7.3 or 18.2 percent, respectively. Even in units with filtration times of more than 3 hours, storage variables were not significantly different from normally filtered or unfiltered units. Filtration times showed a high intraindividual correlation. CONCLUSION: Leukodepletion of AWB results in a diminished preoperative deposit of RBCs that is pronounced in units with prolonged filtration. The quality of the latter suggests that it is not justified to discard AWB units with prolonged filtration times. Prolonged filtrations are related to patient characteristics that have yet to be defined.