Remodelling whole blood processing through automation and pathogen reduction technology at the Luxembourg Red Cross.

In 2014-2015, the Luxembourg Red Cross (LRC) implemented a fully automated system (FAS) able to process 4 whole blood units simultaneously, and a pathogen reduction technology (PRT) based on riboflavin and ultraviolet light to improve safety of platelet concentrates (PCs). In this observational study, the impact of both technologies to enable this centralised blood transfusion centre to provide safe and timely blood components supply for the whole country was analysed. Standard quality control parameters for blood components, productivity and safety were compared from data collected with the conventional semi- automated buffy coat method and with FAS/PRT. The FAS decreased processing time when compared with the buffy coat method and facilitated the daily routine at the LRC. Red blood cell concentrates, plasma units and PCs prepared with both methods were conform to the European Directorate for the Quality of Medicines & HealthCare specifications. PCs prepared by FAS showed high yields, with decreased variability when the device-related software (T-Pool Select) was used. PRT had minimal impact on platelet yields and product quality and induced no increase in transfusion reaction notifications. The FAS and PRT transformed the daily routine of blood component manufacture by allowing increased productivity and efficiency, notwithstanding resource containment and without impacting quality, yet promoting safety.

Combined Platelet and Erythrocyte Salvage: Evaluation of a New Filtration-based Autotransfusion Device.

BACKGROUND: The SAME device (i-SEP, France) is an innovative filtration-based autotransfusion device able to salvage and wash both red blood cells and platelets. This study evaluated the device performances using human whole blood with the hypothesis that the device will be able to salvage platelets while achieving a erythrocyte yield of 80% and removal ratios of 90% for heparin and 80% for major plasma proteins without inducing signification activation of salvaged cells. METHODS: Thirty healthy human whole blood units (median volume, 478 ml) were diluted, heparinized, and processed by the device in two consecutive treatment cycles. Samples from the collection reservoir and the concentrated blood were analyzed. Complete blood count was performed to measure blood cell recovery rates. Flow cytometry evaluated the activation state and function of platelets and leukocytes. Heparin and plasma proteins were measured to assess washing performance. RESULTS: The global erythrocyte yield was 88.1% (84.1 to 91.1%; median [25th to 75th]) with posttreatment hematocrits of 48.9% (44.8 to 51.4%) and 51.4% (48.4 to 53.2%) for the first and second cycles, respectively. Ektacytometry did not show evidence of erythrocyte alteration. Platelet recovery was 36.8% (26.3 to 43.4%), with posttreatment counts of 88 × 109/l (73 to 101 × 109/l) and 115 × 109/l (95 to 135 × 109/l) for the first and second cycles, respectively. Recovered platelets showed a low basal P-selectin expression at 10.8% (8.1 to 15.2%) and a strong response to thrombin-activating peptide. Leukocyte yield was 93.0% (90.1 to 95.7%) with no activation or cell death. Global removal ratios were 98.3% (97.8 to 98.9%), 98.2% (96.9 to 98.8%), and 88.3% (86.6 to 90.7%) for heparin, albumin, and fibrinogen, respectively. The processing times were 4.4 min (4.2 to 4.6 min) and 4.4 min (4.2 to 4.7 min) for the first and second cycles, respectively. CONCLUSIONS: This study demonstrated the performance of the SAME device. Platelets and red blood cells were salvaged without significant impact on cell integrity and function. In the meantime, leukocytes were not activated, and the washing quality of the device prevented reinfusion of high concentrations of heparin and plasma proteins.

Fatal sepsis associated with a storage container leak permitting platelet contamination with environmental bacteria after pathogen reduction.

BACKGROUND: Pathogen reduction technology and enhanced bacterial culture screening promise to significantly reduce the risk of transfusion-associated septic reactions due to contaminated platelets. Recent reports suggest that these interventions lack efficacy for post-collection and processing contamination with environmental organisms if the storage bag integrity is compromised. CASE REPORT: We report a fatal septic transfusion reaction in a 63-year-old patient with chronic kidney and liver disease who received a pathogen reduced platelet transfusion in anticipation of surgery. METHODS: The residual platelet concentrate was cultured, with the detected microorganisms undergoing 16S genotype sequencing. Separate pathogen reduction studies were performed on the recovered bacteria, including assessment for amotosalen photoproducts. The storage container was subjected to pressure testing and microscopic examination. Environmental culture screening was performed at the hospital. RESULTS: Gram negative rods were detected in the platelet unit and cultures of both platelet component and the patient's blood grew Acinetobacter baumannii complex, Leclercia adecarboxylata and Staphylococcus saprophyticus. These strains were effectively inactivated with >7.2, 7.7, and >7.1 log10 kill, respectively. The platelet storage container revealed a leak visible only on pressure testing. Hospital environmental cultures were negative and the contamination source is unknown. A. baumannii complex and S. saprophyticus 16S genotyping sequences were identical to those implicated in a previously reported septic reaction. CONCLUSION: Findings are compatible with post-processing environmental contamination of a pathogen reduced platelet concentrate via a non-visible, acquired storage container leak. Efforts are warranted to actively prevent damage to, and detect defects in, platelet storage containers, and to store and transport components in clean environments.

Platelet transfusion: The effects of a fluid warmer on platelet function.

Platelet (PLT) transfusions are an important component of hemostatic resuscitation. The AABB has published several guidelines recommending that PLT units should not be infused through blood warming devices. STUDY DESIGN AND METHODS: Thirty-one units of hospital blood bank apheresis PLTs were obtained. PLT-rich plasma (PRP) aggregometry and thromboelastography (TEG) were performed on the unit samples before and after the units were infused through a Ranger blood/fluid warming device. RESULTS: There were no differences in any of the aggregometry results before and after infusion of the PLTs through the blood warmer (all P > .32). There was a significant reduction in the TEG maximum amplitude (MA) of 69.8 ± 7.9 mm before and 66.0 ± 8.8 mm after (P < .001) infusion of the PLTs through the blood warmer and α angle 61.8 ± 9.4° before and 59.3 ± 8.2° after (P = .044) infusion of the PLTs through the blood warmer, although both mean values were within normal range for the TEG and not clinically significant. There were very good correlations of aggregometry and TEG results before and after infusion of the PLTs through the blood warmer device. CONCLUSION: This study did not demonstrate significant deleterious effect on PLT function from infusing apheresis PLT units through a blood warming device by PRP aggregometry. We did detect a statistically significant-but not clinically significant-reduction in TEG MA and α angle. The prohibition of transfusing PLT units though the Ranger blood warming device is not indicated.

Stored platelet number and viscoelastic maximum amplitude are not altered by warming or rapid infusion.

BACKGROUND: Platelet transfusion is an important aspect of hemostatic resuscitation. Leading textbooks recommend never infusing platelets through warmers or rapid infusers, but there is no evidence to justify this position. MATERIALS AND METHODS: We obtained units of apheresis platelets in plasma from our hospital blood bank and drew a baseline sample from every unit. In the warmer arm, an aliquot from each unit was injected into a fluid warmer heated to 41°C (Ranger, 3M Corporation). After 5 minutes' incubation, the aliquot was withdrawn and sampled. In the infuser arm, we ran the remainder of the unit through a rapid infuser (RI-2, Belmont Instrument Corporation) at 500 mL/min while warmed, and obtained a sample from the outflow line. A platelet count and viscoelastic maximum amplitude (Haemonetics) was measured from every sample. RESULTS: We observed no clotting or device malfunctions. Average postwarmer temperature was 41.8°C (range, 41.0-43.0). There was no significant difference in postwarmer platelet count or viscoelastic maximum amplitude. Average postinfuser temperature was 37.4°C (range, 36.1-39.0). All units reached the goal infusion rate of 500 mL/min. There was a small increase in postinfuser platelet count. There was no significant change in postinfuser viscoelastic maximum amplitude. CONCLUSION: We were unable to detect any effect of warming or rapid infusion on the number or viscoelastic maximum amplitude of stored apheresis platelets. Contrary to common teaching, these results suggest that rapid infusion and warming does not meaningfully harm apheresis platelets.

Assessing Safety of Pneumatic Tube System (PTS) for Patients with Very Low Hematologic Parameters.

BACKGROUND Preventive interventions save lives during the process of chemotherapy for hematologic malignancies, when a hematology laboratory can ensure accurate results. The use of a pneumatic tube system (PTS) is associated with measurement errors and unnecessary transfusions. The aim of this study was to evaluate pre-analytical errors associated with transportation method (PTS versus hand-delivered) and to investigate whether there are unnecessary transfusion events in pancytopenia leukemia patients with very low hematological parameters. MATERIAL AND METHODS A total of 140 paired blood collections were performed for hemogram and biochemistry assays. Paired EDTA and serum gel blood samples were collected from 58 cases with acute leukemia on different days. For each pair, one sample was hand-delivered by a courier (Group 1) while the other sample was transported through a PTS (Group 2). RESULTS The hand-delivered method showed that some platelet transfusions were unnecessary for different thrombocyte cut-off values. Calculated unnecessary platelet (PLT) transfusion ratios when using PTS (PLT <30×10³/µL, 16.3%; PLT <25×10³/µL, 16.4%; PLT <20×10³/µL, 80.3%; PLT <15×10³/µL, 48.6%; and PLT <10×10³/µL, 150.0%) were found to be statistically significant (p=0.002, p=0.046, p<0.000, p=0.028, and p<0.000, respectively). In contrast, for RBC transfusion ratios, although the ratios were high in Group 2, we found no significant difference between the two groups; (HGB <8.0 g/dL, 23.3%; HGB <9.0 g/dL, 25.0%, HGB<10.0 g/dL, 19.3%) and (p=0.002, p=0.085, p<0.160, and p=0.235, respectively). CONCLUSIONS Although our results cannot be universally applied, physicians should be careful, skeptical, and suspicious of transfusion decisions in hematology clinics and consider potential analytical and pre-analytical errors in cases of severe cytopenia when using PTS.

Platelet transfusion in chemotherapy patients: comparison of the effect of intravenous infusion pumps versus gravity transfusion.

Platelet concentrates are given to patients suffering with severe thrombocytopenia usually by a gravity transfusion procedure. Increasing patient numbers that are in need of this treatment increase the pressure on hospital staff and space. In order to combat time issues, the use of medical devices such as intravenous infusion pumps are thought to be beneficial for time and simultaneously for safety in transfusion practices. By using infusion pumps, platelet concentrates can be transfused in less time and provide accurate volume measurements. Manufacturers of infusion pumps claim that these devices are safe to be used for blood products including platelet concentrates. However, published studies were performed on older models and newer devices are on the market now. The purpose of this study is to evaluate infusion pumps, which are claimed to be suitable for blood products and to investigate the impact the pumps had on platelets. Furthermore, the study revealed if the intravenous infusion pumps are safe to be used for platelet transfusion as claimed by manufacturers. A simulated transfusion was performed using the Carefusion Alaris GP Plus volumetric pump and Fresenius Kabi Volumat Agilia infusion pump. Samples were taken from expired platelet concentrates before and after passage through the pump. All samples were investigated for full blood count that included platelet count, mean platelet volume (MPV), platelet distribution width (PDW) and a plateletcrit (PCT). The samples were then centrifuged to achieve platelet-poor plasma and then tested for lactate dehydrogenase (LDH). A power calculation performed on the statistical power analysis program G*power indicated a requirement of 82 samples for a power of 80%. Statistical analysis was performed with the IBM SPSS statistic software. A paired sample t-test was used to calculate mean, standard deviation and P values for the infusion pumps used. The Wilcoxon Signed Rank Test was used to evaluate results that had a non-normal distribution. No statistically significant changes were found for LDH, PDW and platelet count with the Carefusion infusion pump. PCT and MPV were found to have a statistically significant change with P values of 0.005 and 0.001, respectively, and showed a decrease in their values. The Fresenius Kabi infusion pump has shown no statistically difference in LDH, platelet count, PCT or PDW, with P values of 0.075, 0.425, 0.151 and 0.397, respectively. The MPV showed a statistically significant decrease in its value with a P value < 0.043. Although only two pumps were tested, the results achieved by testing the devices revealed that there was no influence on the platelet enzyme LDH or the platelet count as the main parameters. However, the findings showed that there was statistically significant differences in MPV of the expired platelet concentrates.

Propagation capacity of bacterial contaminants in platelet concentrates using a luciferase reporter system.

INTRODUCTION: Currently the use of molecular tools and techniques of Genetic Engineering in the study of microbial behavior in blood components has replaced the employment of classical methods of microbiology. This work focuses on the use of a novel lux reporter system for monitoring the contaminating propagation capacity of bacteria present in platelet concentrates under standard storage conditions in the blood bank. METHODS: A miniTn5 promotor probe carrying the lux operon from Photorhabdus luminiscens (pUTminiTn5luxCDABEKm2) was used to construct four bacterial bioluminescent mutants: Escherichia coli, Salmonella typhi, Proteus mirabilis and Pseudomonas aeruginosa. Luminescent mutants were used for contamination tests with 20 CFU in platelet concentrates bags and were stored under standard storage conditions in the blood bank (100 rpm at 22 °C). The measurements of luminous activity and optical density were used to monitor bacterial proliferation during 7 days (168 h). RESULTS: During the exponential growth phase (log) of bacterial strains, a lineal correlation between luminous activity vs biomass was observed (R(2) = 0.985, 0.976, 0.981) for E. coli::Tn5luxCDABEKm2, P. mirabilis::Tn5luxCDABEKm2 and P. auriginosa::Tn5luxCDABEKm2, respectively. The above indicates that metabolic activity (production of ATP) is directly related to biomass in this phase of microbial growth. While conducting experiments, the inability to propagate S. typhi::Tn5luxCDABEKm2 was detected. We can speculate that platelet concentrates contain specific components that prevent the propagation of S. typhi. CONCLUSION: The use of luxCDABE system for the quantification of luminous activity is a rapid and sensitive alternative to study the propagation and auto-sterilization of bacterial contaminants in platelet concentrates.

Implementation of a new platelet pooling system for platelet concentrates led to a higher corrected count increment after transfusion: a comparative observational study of platelet concentrates before and after implementation.

OBJECTIVES: To study the effect of extended storage of platelet concentrates (PCs) and the implementation of a new platelet pooling system for PCs on corrected count increment (CCI) after transfusion. BACKGROUND: Due to new developments and changes in processes or procedures, one should remain alert for the effects of these changes. Besides in vitro studies and validation, in vivo studies are also important, as it has been shown that in vitro results do not always predict in vivo outcomes. METHODS/MATERIALS: After introduction of extended storage of PCs for 5-7 days prepared from five buffy coats and plasma, transfusion monitoring for transfusions of PCs in haemato-oncological patients was set up. After 9 months, a new pooling system for PCs was implemented, Composelect instead of Optipure PLT, and transfusion monitoring was continued for another 8 months. The CCI was used as primary outcome. RESULTS: In total, 93 patients were included and transfused with PCs prepared in the Optipure PLT system (262 transfusions) or in the Composelect system (127 transfusions). Extended storage of PCs for 7 days had no significant effect on CCI. Although the implementation of the Composelect system did not influence the CCI1 h (13.8 ± 6.0 vs. 13.0 ± 5.8; n.s.), it seemed to have a positive effect on CCI24 h (7.0 ± 4.9 vs. 4.7 ± 4.5; P < 0.05). CONCLUSION: Although the influence of confounders could not be excluded, it seemed that implementation of the Composelect system for PCs led to an improved CCI24 h and that extended storage of PCs did not influence the CCI.

The effect of 24 h resting of old PCs at 22-24°Ð¡ in permeable bags on in vitro platelet parameters.

BACKGROUND: During transporting periods, platelet (PLT) concentrates (PCs) usually undergo a long period without agitation. Whether this interruption, improves quality and viability, or has deleterious effect at 72 h stored PCs, is here investigated. The aim of our study is to investigate effect of metabolic resting (24 h interruption of agitation) versus continue agitation of 72 h-stored PCs (old), prior to transfusion in the blood bank of Tehran. STUDY DESIGN AND METHODS: PCs were prepared using the platelet-rich plasma (PRP) method and stored in the permeable bags in the shaker/incubator, for 72 h at 20-24°C. Then by simply stopping the agitator, PCs remained at stationary condition without agitation for 24 h (WA24h) before sampling. In vitro measurements of PLT quality were carried out just after the termination of interruption period, and the results were compared with continuously agitated platelet within the same day (designated as control group, CA). In vitro variables which are measured were pH, Platelet count, swirling, Ristocetin-induced aggregation (GPIb-related function), LDH, PF4 release and P-selectin expression (activation marker). RESULTS: Compared with control group, the mean platelets PF4 release and P-selectin expression showed no significant differences (p=0.101, p=0.739 respectively). The mean level of pH was not significant (p=0.156); WA24h (7.12±0.14) and CA (7.17±0.11). Also Ristocetin-induced aggregation study showed significant differences (p=0.0281) between CA (76.6±3.2) and WA24h (62.69±21.43). Other in vitro variables between CA and WA groups including swirling, Platelet count and LDH showed no significant differences after 72 h of storage. CONCLUSIONS: We observed that 24 h resting of old PCs (WA24h) at 22-24°Ð¡ in permeable bags preserved pH, swirling, LDH, Ristocetin-induced aggregation and platelet's activation as good as control group after 72 h of storage.

[Clinical efficiency of transfusion of pathogen-inactivated platelet concentrates].

AIM: To evaluate the effect of pathogen-inactivated platelet concentrates (PIPC) on posttransfusion platelet increments, hemorrhagic syndrome relief, and transfusion intervals. SUBJECTS AND METHODS: This prospective study included 29 hemoblastosis patients (13 women, 16 men), median age 38 years (20-66 years). Pathogens were inactivated by the photodynamic method using the Intecept system. Each patient received two PC transfusions: one PIPC transfusion and one control one. Posttransfusion platelet increments one hour and one day after PC transfusion, the course of hemorrhagic syndrome, and the time to next platelet transfusion were analyzed. RESULTS: Pathogen inactivation with amotosalen and ultraviolet irradiation reduced posttransfusion platelet increments in recipients by 24% after one hour and by 29% after one day after PIPC transfusion versus control ones. CONCLUSION: The clinical efficiency of transfusions of amotosalen-induced PIPC was comparable with that of untreated platelet concentrates. Despite a reduction in post-transfusion platelet increment with the use of PIPC, this caused no significant increase in the frequency of transfusions.

Cryoprecipitate and platelet administration during modified ultrafiltration in children less than 10 kg undergoing cardiac surgery.

UNLABELLED: The timing of blood product administration after cardiopulmonary bypass (CPB) may influence the amount of postoperative transfusion and chest tube output. We performed a retrospective study of a novel technique of administering blood products during modified ultrafiltration (MUF) in congenital cardiac surgery. A Control Group (CG; n = 55) received cryoprecipitate and platelets after modified ultrafiltration. The Treatment Group (TG; n = 59) received cryoprecipitate and platelets during MUF. Volumes of blood products transfused in the operating room, initial coagulation parameters in the cardiac intensive care unit, and first 24-hour chest tube output were recorded. Age (116 +/- 198 versus 84 +/- 91 days), weight (4.6 +/- 1.8 versus 4.5 +/- 1.4 kg), duration of bypass (121 +/- 50 versus 139 +/- 57 minutes), and Aristotle scoring (9.3 +/- 2.7 versus 9.1 +/- 3.1) were not significantly different when comparing the control and treatment groups, respectively. Intraoperative packed red blood cells (74.4 +/- 34.8 versus 79.3 +/- 58.0 mL/kg, p = .710), fresh-frozen plasma (58.3 +/- 27.1 versus 59.1 +/- 27.2 mL/kg, p = .849), cryoprecipitate (7.3 +/- 5.1 versus 8.6 +/- 5.9 mL/kg, p = .109), and platelet (19.0 +/- 14.6 versus 23.7 +/- 20.8 mL/kg, p = .176) administration were the same in the control and treatment groups, respectively. However, fibrinogen levels on arrival in the coronary intensive care unit were significantly higher (305 +/- 80 versus 255 +/- 40 mg/dL, p < .001) in the CG compared with the TG. Twenty-four-hour chest tube output was not significantly different but the CG (17.76 +/- 9.34 mL/kg/24 hours) was trending lower than the TG (19.52 +/- 10.94 mL/kg/24 hours, p = .357). In an attempt to minimize CPB-associated bleeding and transfusions, we changed our practice by adjusting the timing of blood product administration after patient separation from CPB. The goals of the change in practice were not measurably different in terms of shorter intraoperative times, fewer blood transfusions, or less chest tube output at our institution. KEYWORDS: congenital heart disease, modified ultrafiltration, cryoprecipitate, platelets, cardiopulmonary bypass.

Combined plasma exchange and platelet transfusion in immune-mediated thrombocytopenic emergencies.

Refractory immune-mediated thrombocytopenia (ITP) can be very difficult to manage, especially if associated with a hemorrhagic or surgical emergency. We report two cases of refractory ITP that were unresponsive to routine therapeutic interventions and frequent platelet transfusions. A combination of plasma exchange and platelet transfusion successfully raised the platelet count to a level that permitted life-saving surgical interventions. Plasma exchange in these two cases likely reduced platelet antibodies significantly, decreasing platelet destruction. We propose that a trial of combination plasma exchange and platelet transfusion can be attempted in emergent thrombocytopenic situations with an underlying immune mechanism.

Clinical application of platelet-rich fibrin by the application of the Double J technique during implant placement in alveolar bone defect areas: case reports.

Platelet-rich fibrin (PRF) belongs to a new generation of platelet concentrates, with simplified processing and without biochemical blood handling. PRF releases growth factors and matrix glycoproteins. In this study, the Double J technique was used. The Double J technique, which uses centrifuged venous blood that is sampled using 2 different types of DB vacutainers, is a procedure that covers the PRF matrix obtained from 1 of the DB vacutainers on transplanted osseous coagulum, which is obtained using the plasma layer and buffering layer from the second DB vacutainer. Two cases were reported because clinically valid results were obtained. Additional studies are definitely warranted.

A proposed protocol for the standardized preparation of PRF membranes for clinical use.

Upon clinical application, thick platelet-rich fibrin (PRF) is usually compressed to fit the implantation site. However, it is speculated that the preservation of platelets and plasma content depends on the compression methods used. To accurately evaluate the clinical outcome of PRF, the preparation protocol should be standardized. Freshly prepared PRF clots were compressed into a thin membrane by our novel PRF compression device. The localization of platelets was examined by SEM and immunostaining. Growth factor levels were evaluated by bioassays and cytokine-antibody array techniques. The angiogenic activity was examined by the chick chorioallantoic membrane assay and the scratch assay using HUVEC cultures. Platelets were concentrated on the surface of the region adjacent to the red thrombus and this region was subjected to the experiments. Compared to the PRF membrane compressed by dry gauze (G-PRF), the preservation of the plasma content, 3D-fibrin meshwork, and platelets was more intact in the compressor-prepared PRF membrane (C-PRF). Among the growth factors tested, C-PRF contained PDGF isoforms at higher levels, and significantly stimulated cell proliferation and neovascularization. C-PRF may be useful for grafting while minimizing the loss of bioactive factors. This C-PRF preparation protocol is proposed as a standardized protocol for PRF membrane preparation.

Storage of aliquots of apheresis platelets for neonatal use in syringes with and without agitation.

BACKGROUND: To facilitate volume control in neonates, platelets (PLTs) are aliquoted and stored for short periods in non-gas-permeable syringes before infusion. Although agitation of PLTs during storage in gas-permeable bags is performed to maintain their quality, the effect of syringe agitation during storage is unknown. STUDY DESIGN AND METHODS: Double apheresis PLTs (n = 6) were collected and split, providing two identical products. On Days 2 and 4 of storage, aliquots from one bag of each pair were transferred to two syringes and stored for 6 hours on flatbed agitator or were left at 20 to 24 °C without agitation. A series of in vitro tests was performed on Days 0, 2 (Hours 0 and 6), and 4 (Hours 0 and 6). Control samples were obtained from the second matched bag that was stored on the agitator. Data were analyzed by one-way analysis of variance with differences considered significant if the p value was less than 0.05. RESULTS: Comparable results for several PLT variables were obtained with or without agitation of the syringes. On Day 4 Hour 6, pH values were 7.18 ± 0.12 (agitated syringes) and 7.19 ± 0.1 (nonagitated syringes), and extent of shape change and hypotonic shock response measurements were not significantly different between agitated syringes and nonagitated syringes (23.7 ± 6.4 and 74.3 ± 9.8% vs. 23.3 ± 5.4 and 76.0 ± 7.6%), respectively. CONCLUSION: Based on in vitro testing, apheresis PLT aliquots can be stored in syringes for at least 6 hours without agitation before transfusions.

Comparison of the platelet concentrations obtained in platelet-rich plasma (PRP) between the GPS™ II and GPS™ III systems.

INTRODUCTION: Platelet growth factors are known for their ability to speed up tissue healing (bone, skin, tendons, muscle). Various techniques make it possible to collect this platelet-rich plasma or PRP. METHODS: This study compares the platelet concentrations obtained from five patients using GPS™ III, which has recently come onto the market, with those obtained using GPS™ II. RESULTS AND CONCLUSION: We obtain a platelet concentration that is six to nine times greater with GPS ™ II and GPS™ III, but there is no significant difference between the concentrations of PRP obtained with the two systems.

Transfused stored platelets have the same haemostatic function as circulating native platelets.

BACKGROUND AND OBJECTIVES: As thrombelastography (TEG) measures haemostasis in whole blood, we used this instrument to study whether transfused platelets (PLTs) have the same haemostatic function compared to native circulating PLTs. Further, we studied the effect of storage time on the haemostatic potential of platelet concentrates (PCs). MATERIALS AND METHODS: During the decrease in PLT count after chemotherapy, TEG parameters were measured serially until the transfusion trigger was reached in 92 patients. TEG parameters for different ranges of native circulating PLTs could be assessed, which were compared to ranges obtained in the thrombocytopenic period in which the patient received PLT transfusions. Finally, we compared the haemostatic potential of fresh PCs (1-3 days) with PCs with longer storage time (4-5 days). RESULTS: No differences could be found in haemostatic potential between native PLTs and transfused stored PLTs (all P-values > or = 0.1). The transfusion of fresh PLTs demonstrated better haemostatic effects than longer stored PLTs, measured 1 h after transfusion. Both the time until a fixed level of clot firmness was reached (K-time) and the rate of clot growth (alpha angle) were superior for fresh PCs. CONCLUSION: TEG is able to monitor the haemostatic effects of PLT transfusion, with comparable haemostatic properties of native circulating and transfused stored-PLTs. Further, our data suggest that limited storage time is associated with a better haemostatic capacity. However, before TEG can be applied as a qualitative test in PLT transfusion, further research is needed with focus on clinical outcomes like bleeding episodes.

[Analysis of a severe septic transfusion reaction with standard platelet concentrate]. / Analyse d'un incident bactérien grave transmis par transfusion d'un concentré plaquettaire.

We recently observed a near fatal case of transfusion-transmitted infection with standard platelet concentrate. Streptococcus dysgalactiae subspecies equisimilis was isolated both from donor, residual component container and cultures of the patient's blood. This should question the usefulness of systematic bacterial detection in platelet concentrates, however a lethal accident has occurred recently which escaped bacterial detection. This observation calls for implementation of pathogen inactivation procedures for platelets concentrates.