Quality assessment of the preparation and storage of leukocyte-depleted pooled platelet concentrates

OBJECTIVE

To explore the feasibility of using a disposable platelet storage bag containing a leukocyte filter to prepare leukocyte-depleted pooled platelet concentrates with the buffy coat method.

METHODS

150 bags of whole blood samples (400 mL/bag) were stored overnight at 22 ± 2°C, and buffy coats were separated on Day 2, then 5 units of ABO homotypic buffy coat and 1 unit of plasma were pooled into a disposable platelet storage bag containing a leukocyte filter to prepare leukocyte-depleted pooled platelet concentrates and stored in a Platelet Agitator. On Day 2, 4, 5 and 7 after the collection of whole blood, platelet content, pH value, pO2, pCO2, glucose (GLU), ATP, and other quality indicators were measured.

RESULTS

The quality indicators of leukocyte-depleted pooled platelet concentrates met the requirements for leukocyte-depleted aphaeresis platelets in the Chinese national standard Quality Requirements for Whole Blood and Blood Components (GB18469-2012). With the prolongation of storage time, MPV and PDW of platelets gradually increased, pH value, bicarbonate, and GLU gradually decreased, LA, LDH, and ATP gradually increased, pO2 slightly increased, pCO2 decreased, and HSR had no significant change. ESC decreased significantly on Day 7, CD62p decreased first and then increased, sP-selectin and GP V increased first and then decreased, but the results on Day 7 were higher than those on Day 2.

CONCLUSION

The quality of leukocyte-depleted pooled platelet concentrates prepared by the buffy coat method using disposable platelet storage bags containing a leukocyte filter was comparable to that of leukocyte-depleted apheresis platelets, and could be used clinically.

Discussion on the recruitment strategy for apheresis platelet donors in Chongqing during a public health emergency. Front Public Health 2024;12:1365433. [PMID: 38651129 PMCID: PMC11034425 DOI: 10.3389/fpubh.2024.1365433] [Citation(s) in RCA: 0] [Impact Index Per Article: 0]

Objective

This study aimed to analyze the population characteristics of apheresis platelet donors in Chongqing Province and provide a scientific basis for the development of precise and efficient recruitment strategies. The ultimate goal is to increase the number of regular platelet donors in preparation for public health emergencies.

Methods

This study involved 53,089 blood donors who donated apheresis platelets to the Chongqing Blood Center from 2020 to 2022. Data regarding age, sex, blood type, education level, occupation, and frequency of blood donation were collected and analyzed to identify factors influencing platelet donation.

Results

Between 2020 and 2022, the majority of apheresis platelet donors in Chongqing were aged 25-35 years, with a male-to-female ratio of 2.6:1. The ABO blood group distribution was O > A > B > AB. The apheresis platelet donors mainly consisted of college students, and the donors who had donated only once accounted for the greatest proportion.

Conclusion

Based on the population characteristics of apheresis platelet donors in Chongqing, blood collection and supply organizations must refine emergency blood collection and supply plans during public health emergencies. This study underscores the importance of developing precise and efficient recruitment strategies for apheresis platelet donors and expanding the pool of regular apheresis platelet donors. These measures are essential to ensure the timely, safe, and effective use of clinical blood resources during public health emergencies.

The impact of donor biological variation on the quality and function of cold-stored platelets

BACKGROUND AND OBJECTIVES

Room temperature-stored platelets (RTPs) maximize platelet viability but limit shelf life. The aims of this study were to investigate the impact of donor variability on cold-stored platelets (CSPs) and RTP, to determine whether RTP quality markers are appropriate for CSP.

MATERIALS AND METHODS

Double platelet donations (n = 10) were collected from consented regular male donors stored in 100% plasma. A full blood count, donor age, weight, height and body mass index (BMI) were collected at the time of donation. Platelet donations were split equally into two bags, and assigned to non-agitated CSP or agitated RTP. The quality and function of platelets were assessed throughout the standard 7 days of storage and at expiry (day 8). Non-parametric statistical analyses were used to analyse results given the small sample size.

RESULTS

As expected, there were significant differences between CSP and RTP throughout storage including a reduction in CSP concentration as well as a loss of swirling. Furthermore, a significant increase in CSP exhibiting activation and apoptotic markers was observed. Platelet concentrations were further impacted by donor BMI, and donors with the highest BMI (>29) had the lowest platelet concentration and activation response at the end of CSP storage.

CONCLUSION

Platelet quality and functionality play a vital role in transfusion outcomes; however, blood components are inherently variable. This study demonstrated, for the first time, the specific impact of donor BMI on CSP quality and function and highlights the requirement for novel quality markers for assessing CSPs.

Acquired platelet storage container leaks and contamination with environmental bacteria: A preventable cause of bacterial sepsis

Background

Apheresis platelets (AP) may be contaminated by environmental bacteria via container defects acquired during processing, transport, storage, or transfusion, as highlighted by a recent series of septic reactions related to Acinetobacter spp. and other bacterial strains.

Study design and methods

The frequency and nature of acquired container defect reports to one manufacturer were evaluated from January 2019 to July 2020. The published incidence of contamination and sepsis due to environmental bacteria with culture screened AP in the United States was reviewed for the period of 2010–2019.

Results

Review of a manufacturers' records showed 23 US reports of leaks involving 24 containers attributed to postmanufacturing damage, at a rate of 44 per million distributed storage containers. Analysis of returned containers showed evidence of scratches, impressions, and/or piercings. Literature review of US hemovigilance data revealed that environmental bacteria comprised 7% of confirmed positive primary bacterial culture screens, were responsible for 14%–16% of reported septic, and 8 of 28 (29%) fatal reactions with bacterial‐culture screened AP. Sepsis cases have been reported with culture screened, point‐of‐issue (POI) tested, or pathogen‐reduced AP.

Discussion

Environmental contamination of AP is rare but can cause sepsis. Container damage provides a pathway for contamination after culture screening, POI bacteria testing, or pathogen reduction. Blood collectors and transfusion services should have procedures to ensure proper inspection, handling, storage, and transport of AP to avoid damage and should enhance efforts to detect defects prior to release and to eliminate bacteria from all contacting surfaces to minimize the risk of contamination.

Donor citrate reactions influence the phenotype of apheresis platelets following storage

BACKGROUND

Platelet collection and processing methods, as well as donor attributes, can influence platelet function and quality during ex vivo storage. In this study, activation and procoagulant responses in platelets collected from donors experiencing a citrate reaction (CR) were investigated.

STUDY DESIGN AND METHODS

Apheresis platelet components (n = 54) were stored in 100% autologous plasma and tested on days 1 and 5 post-collection. Platelet components were categorized into two groups according to whether the donor had experienced a CR during donation (n = 10; non-CR group, n = 44). Platelet aggregation was initiated with collagen and thrombin. Platelet phenotype was characterized by flow cytometry. Fibrinogen binding was assessed following collagen + thrombin stimulation (COATed platelets), and procoagulant activity was assessed using a procoagulant phospholipid assay (PPL). Platelet microparticle (PMP) subsets were enumerated by flow cytometry.

RESULTS

Basal von Willebrand factor (VWF) binding was higher in the CR donations when compared with the non-CR group. Collagen aggregation was significantly higher in platelets from CR donations, in contrast to aggregation induced by thrombin. The proportion of phosphatidylserine (PS) positive PMP and PPL clotting time were higher in the CR group, in contrast to the number of basal PS⁺ platelets and COATed platelets following stimulation.

CONCLUSION

Platelets donated by donors who experienced a CR during donation had higher platelet activation response and possibly a more procoagulant PMP phenotype, suggesting that this donor reaction might lead to increased platelet activation.

Passive anti-C acquired in the setting of Rh immune globulin administration following Rh mismatched apheresis platelet transfusion: A case series

Rh immune globulin (RhIG) may be administered to Rh(D)-negative recipients of Rh(D)-positive platelet (PLT) transfusions to mitigate anti-D alloantibody formation. We report a series of seven patients in which anti-C was detected as a result of RhIG administered as immunoprophylaxis following Rh-mismatched apheresis PLT transfusion, persisting for a range of 27 to 167 days post-RhIG. The passively transferred anti-C antibodies created complexities for subsequent transfusion support. Based on these challenges, in combination with emerging evidence supporting an extremely low anti-D alloimmunization risk following Rh-mismatched apheresis PLTs, we have changed our practice and now limit RhIG immunoprophylaxis in this setting to women of reproductive age. In summary, the blood bank and apheresis communities should be aware that passive transfer of non-D antibodies is possible following RhIG administration. This phenomenon represents a compelling reason to consider the risk/benefit ratio of RhIG and to limit its use to situations in which it is clinically necessary.

Implications of a switch to a 100% apheresis platelet supply for patients and for blood donors: a risk benefit analysis

BACKGROUND

A 100% apheresis platelet supply is considered to increase transfusion safety by lowering donor exposures for transfusion recipients. We performed a risk benefit analysis to contrast the reduction of donor exposures and the risk of contaminated blood products in the nation-wide inventory with the donor risks associated with a switch to a 100% apheresis platelet supply in Germany.

METHODS

Donor exposures and the number of contaminated blood products resulting from HIV-like, HBV-like, HCV-like pathogens and two theoretical agents with infection rates of 10 and 1000 in 100 000, respectively, were calculated for a 100% apheresis platelet supply in Germany based on the 2006-2012 hemovigilance reports. These numbers were compared with the current mixed platelet supply of pooled and apheresis platelets. Moreover, additional donation time and apheresis donor complications resulting from a 100% apheresis platelet supply were estimated.

RESULTS

Per million total blood products (red cells, platelets, fresh frozen plasma), a 100% apheresis platelet supply would reduce donor exposures by 87 100 and the number of contaminated blood products ranging from 0·8 to 871·1. On the other hand, this requires additional 29 478 apheresis donations, 3·4 years additional donor time, and would be associated with 58 additional donor complications, respectively.

CONCLUSIONS

A 100% apheresis platelet supply would reduce donor exposures and the number of contaminated blood products in the inventory, but would increase apheresis complications in donors. Potential risks for patients must be carefully weighed against the risks for donors, dependent on the specific pathogen scenario.

Clinical and quality evaluation of apheresis vs random-donor platelet concentrates stored for 7 days

BACKGROUND AND OBJECTIVES

The clinical efficacy of different types of platelets remains under debate. We conducted a pilot study to prospectively evaluate the impact of subsequent storage on the in vitro quality and post-transfusion outcome of apheresis prepared platelets (APCs) vs random donor platelets (RDPs).

MATERIALS AND METHODS

We studied 30 units of APCs, and 30 units of RDPs. We performed assays on days 1, 3, 5 and 7, evaluating ADP aggregation, platelet count and pH. Fifteen thrombocytopenic patients with haematologic conditions were evaluated. Each patient received prophylactic transfusions of both components, and their post-transfusion platelet increments were compared. Twenty-five transfusions were apheresis prepared, and 35 transfusions were received as RDPs. None of the RDPs were leukoreduced.

RESULTS

The median platelet counts for APCs on days 1, 3, 5 and 7 were; 2070, 1990, 1680 and 1240 × 10(3)  µL(-1) , respectively, and were; 1290, 850, 499 and 284 × 10(3)  µL(-1) , respectively for RDPs. The pH of all units was more than 6·2. Both groups demonstrated a significant decrease of ADP aggregation after 3 days of storage (P < 0·05). However, APCs provided satisfactory increments for 90·9% of transfusions. On the sixth and seventh days of storage, APCs provided significantly higher platelet increments (18·7 × 10(3)  µL(-1) ) compared with RDPs (3·20 × 10(3)  µL(-1) ) (P < 0·05). Significantly longer transfusion intervals were also achieved with APCs (P < 0·05).

CONCLUSION

Although other variables may have confounded the results, subsequent storage of APCs appeared to provide higher increments with longer intervals of transfusion compared with RDPs. Future prospective studies are needed, adjusting for other possible confounding variables.

Supply with Platelet Concentrates from the Point of View of a Blood Donation Service of the Bavarian Red Cross

SUMMARY: BACKGROUND: It is known that pooled platelet concentrates derived from buffy coat (PCs) have several disadvantages compared to platelet concentrates produced by platelet apheresis (APCs). Therefore, all blood products issued by the Bavarian Red Cross blood banks (BSD/BRK) (18,000 products/year) were produced by single donor apheresis. The main reason not to produce PCs was the elevated viral and bacterial infection risk during the last decade. But also the four-fold increased exposition to HLA and PLA antigens and the poor quality (in the sense of white and red cell contamination) of PCs (especially the ones produced with the platelet-rich plasma method) played a role to abstain from these products. MATERIAL AND METHODS: We performed a risk assessment to evaluate both products with regard to the actual testing and production methods, considering recently published data. However, a statistical calculation of the risks associated with the use of PCs or APCs with regard to different infectious agents with various prevalences was not done. RESULTS: The dramatically reduced risk for the transmission of HIV, HBV or HCV accompanying the implementation of improved antibody tests and of NAT minipool testing, the introduction of 100% leukocyte filtration, the conversion of PC production from the platelet-rich to the buffy coat method, and recent data on the risk of transmission of bacterial infections resulted in a equal assessment of APCs and PCs. CONCLUSION: As a consequence of this revised risk assessment, we supply our hospitals with both products APCs and buffy coat-derived PCs (pools of 4 donors). For clinical use we considered both products as equally effective, except for patients who have multiple antibodies and need HLA-typed platelets.

Laparoscopic splenectomy reduces the need for platelet transfusion in patients with idiopathic thrombocytopenic purpura

OBJECTIVES

Laparoscopic splenectomy has been increasingly used in patients with idiopathic thrombocytopenic purpura. Because it is associated with minimal abdominal trauma, platelet consumption could be reduced with the laparoscopic approach. The aim of this study was to analyze intraoperative bleeding and the need for apheresis platelets, comparing laparoscopic with open splenectomy.

METHODS

Records of 40 patients who underwent splenectomy (20 through laparoscopy and 20 through open surgery) for idiopathic thrombocytopenic purpura were retrospectively reviewed. Intraoperative bleeding and need of perioperative apheresis platelets were evaluated in both groups. Statistical evaluation was conducted using the Mann-Whitney rank test, and differences were considered significant at P<0.01.

RESULTS

The mean amount of intraoperative bleeding was less in the laparoscopic group (P<0.01). Apheresis platelets were necessary in all patients in the open group (2 units transfused in 55% and 1 unit in 45% of cases) and only in 30% of cases in the laparoscopic group (1 unit transfused in each case).

CONCLUSIONS

Laparoscopic splenectomy is a safe procedure also in patients at high risk for bleeding diathesis. In idiopathic thrombocytopenic purpura, laparoscopic splenectomy should be the gold-standard surgical treatment. Need of platelet transfusion is probably reduced when laparoscopic splenectomy is compared with open surgery in these patients.