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Background: The OrbiSac system (Sanguistech) is a device which can automatically pool multiple buffy coats (BCs), centrifuge and subsequently express the platelet rich plasma (PRP) into a container. The principle is that a circular bag is placed on top of a flexible compartment containing a liquid. After pooling and centrifugation this compartment is filled, thereby expressing the PRP from the circular bag into a storage container. Purpose: To validate the OrbiSac system for production of pooled platelet concentrates (PCs) in PAS-II additive solution. Methods: Five BCs (50 mL, hematocrit 40%) were welded onto multiple leads that are connected to a circular bag system. The circular bag was placed in the OrbiSac, and the BCs were automatically transferred to this bag. Then, the BC-bags were automatically rinsed by expressing 150 mL PAS-II to all 5 BC-bags. The bags were automatically mixed and the PAS-II was added to the circular bag. After a second rinsing with another 150 mL PAS-II, the tubing of the BC-bags and PAS-II bag were automatically sealed and removed. The OrbiSac automatically mixed the content of the circular bag, and a sample was taken. The circular bag was centrifuged, and after completion of the separation the PRP was expressed to a storage container. We required that the PC contained >240 ×10[sup 9] platelets per unit, <100 × 10[sup 6] white cells (WBCs) and <5 × 10[sup 9] red cells per unit. Results: See table (mean ± SD, n=12). All PCs conformed to our requirements. Platelet recovery was 82±18% of the number of platelets originally present in the BC pool. Processing time was approximately 15 minutes, including pooling, centrifugation and expression of the PRP. We regarded user-friendliness as very good, with a minimum of operator handling as compared to our current production system (i.e. no filling of centrifuge cups, no careful removal from the centrifuge, no careful placing of units in separators). Conclusion: This new system allows fully automated processing of pooled PCs from BCs. For production of WBC-reduced PCs without the use of a filter, the OrbiSac system will be further optimised. [ABSTRACT FROM AUTHOR]

Background: For the release of all blood components HCV-NAT minipool screening (max 48 donations) was implemented in July 1999 and HIV-NAT in November 2000. All blood donations of 10 blood banks are tested in 4 NAT laboratories.¶ Methods: Nucleic acid is extracted from 2 mL pool plasma by automated extraction (Nuclisens, Organon Teknika), amplification and detection (COBAS HCV Ampliscreen 2.0 and HIV Ampliscreen 1.5, Roche). Minipools were made by an automated pipetting machine (Tecan, Genesis). A LIMS was designed (PMS version 3.0 Tecan/Organon Teknika) to link all individual steps of the pipetting and testing procedure and test results are automatically transferred to the various information systems of the blood banks.¶ Results: In the months November 2000 to April 2001 a total of 10,745 and 10,773 tests (pools and controls) were analyzed for presence of HCV-RNA and HIVRNA respectively. In none of the pools a confirmed positive result was observed for both tests. In the HCV-NAT one initially reactive pool was found, whereas 21 pools tested initially positive in HIV-NAT, but were not confirmed by duplicate retesting or subpooling. For HCV-NAT 128 (1.2%) invalid results were observed, due to: technical problems with extractors (n=70 (0.7 %)), problems with COBAS robots (n=58 (0.5 %)).¶ The HCV-RNA spy controls (PELISPY Multimarker, CLB) of 140 geq/mL and 38 geq/mL were detected positive in 99.0 and 92.2% of the analyses respectively. For HIV-NAT 133 (1.2%) invalid results were observed due to: technical problems with extractor (n=62 (0.6 %)) and problems with COBAS (n=71 (0.6%)).¶ The HIV-RNA spy controls (PELISPY Multimarker, CLB) of 140 geq/mL and 38 geq/mL were detected positive in 98.9% and 95.9% of the analyses respectively. All blood products were released within 24 h after collection.¶ Conclusion: This fully automated extraction, amplification and detection procedure for HCV and HIV-RNA, combined a high sensitivity, specificity and robustness for daily routine in the blood bank. [ABSTRACT FROM AUTHOR]

Background: Since July 2000 it was, according to altered national guidelines, no longer allowed to draw whole blood or apheresis products from first time donors (FTD) at their first visit to the blood centre. Since then, the first visit of FTD consists of a medical assessment (risk factors etc) and blood analysis (blood group typing, HBsAg, anti-HCV, anti-HIV, anti-HTLV I/II and TPHA). Donors who passed the medical and laboratory assessment are invited to give blood after one month. The background of this altered procedure is too improve safety of the blood supply by exclusion of high risk FTD before blood products are collected. The number of whole blood donations of FTD before and after implementation of the guideline was compared. Methods: FTD were selected during a period of three months before (group A) and after (group B) implementation of the new guideline. The number of whole blood donations in group A donors was established at their first visit. From group B donors it was recorded if at least one donation was collected in a period of 6 months after their first visit. In that period they were invited at least twice for donation. Results: Group A consisted of 324 FTD and resulted in 288 (89%) whole blood donations. Group B consisted of 394 FTD and resulted in 170 (43%) whole blood donations. Conclusion: Delaying blood collection in FTD after completion of medical and laboratory assessment, results in a significant decrease of blood donations. [ABSTRACT FROM AUTHOR]

Background: For cryopreservation of platelet concentrates (PCs) 5% dimethyl sulfoxide (DMSO) is widely used as cryoprotectant. It was our aim to investigate morphological and thermic changes in PCs after addition of DMSO. Methods: A PC was divided into aliquots of 4 mL each. To each aliquot, 4 mL 10% DMSO in plasma or in PAS-2 was added fast (in a few seconds) or slow (1 mL/min). The DMSO solution was either at RT or cooled to 7 °C. As controls we added (fast) 4 mL of plasma or PAS-2 without DMSO (RT) to the aliquots of PC. Temperature of the PC during addition of DMSO was measured, and morphology of the platelets was scored according to Kunicki (disks 4 points; dendrites 2 points; spheres 1 point) with a maximum score of 400. The experiment was done 6 times. Results: The PC had a mean volume of 43±4 mL and a mean platelet count of 90±15 × 10[sup 9]. Only when cold DMSO solution was added, a rise in temperature was seen as compared to the mean temperature of PC and DMSO solution, probably caused by warming up of the DMSO solution during addition at RT. The PC showed very high morphology scores after addition of DMSO, mean score was 337±14, which was even higher than the scores of the controls. No significant differences in scores were seen between adding DMSO under the various conditions and controls. Conclusions: No or limited heat development, and no significant differences in morphology score of platelets were observed when DMSO was added under various conditions. [ABSTRACT FROM AUTHOR]