Pre-donation Count Research Articles

Determination of Appropriate Deferral Time for Repeat Apharesis Platelets Concentrate Donation in Abuja, Nigeria

Background: Plateletpheresis is the process by which a therapeutic adult dose of platelet concentrate is produced from a single donor using automated cell separator equipment. Recently, the demand for Apheresis Platelets concentrate transfusions has been increasing in our hospitals. This has been attributed to increased cases of malignancy associated bone marrow suppression and various other causes of thrombocytopaenia and thrombopathies. The Increasing use of myeloablative chemotherapy in treatment of haematological and other malignancies also results in transient severe fall in platelet count. The demand generally outstrips the supply necessitating the need to search for additional donor sources to increase the supply of platelets for transfusion. Is it therefore possible to reduce the time interval between plateletpheresis while maintaining donor safety? Aims and Objectives: The aim of the study was to determine the platelets recovery time after platelets concentrate donation with a view to determining the appropriate deferral time for repeat plateletpheresis Methods: The study was conducted at the National Hospital Abuja. Fifty seven healthy plateletpheresis donors were recruited over a period of seven months and their haematological parameters were analyzed on days 0, 2 and 7 post donation. We excluded donors whose pre-donation platelet count were less than 200 x 109/L Results and Analysis: Analysis was done in only forty eight (48) donors as nine (9) participants withdrew before the end of the study. The results show There was a significant decrease in the platelets counts (p <0.001), with subsequent good platelets recovery post donation (Pre: 259.83±44.61 x 109/L; Post - Day 0: 205.29±36.77 x 109/L, day 2: 216.88±32.71 x 109/L and day 7: 240.3±41.83 x 109/L). The apheresis donors recovered 64.29% of the lost platelets by day 2 of donation and subsequently attain 92.49% of pre-donation count within 7 days of donation. There was a statistically significant transient increase in the immediate post donation haemoglobin concentration (14.72±1.32)g/dL but this gradually reduced on day 2 (13.75±1.04)g/dL and 13.83±1.04g/dL on day 7 showing no significant different from the pre-donation Hb of 13.96±1.02g/dL Conclusion: This study has shown statistically significant platelets recovery 7 days after plateletpheresis making a 7 day deferral for repeat plateletpheresis feasible in our environment. The study also shows feasibility of a 2 days deferral as recommended by AABB. Strict monitoring and pre-donation evaluation of donors should be done to prevent any adverse events such as anaemia and thrombocytopenia. Disclosures No relevant conflicts of interest to declare.

First comparative analysis concerning the plasma platelet contamination during MNC collection

Background and objectivesMonocytes can be cultured into dendritic cells with addition of autologous plasma, which is highly prone to platelet contamination due to the apheresis process. Since platelets affect the maturation process of monocytes into dendritic cells and might even lead to a diminished harvest of dendritic cells, it is very important to reduce the platelet contamination. A new collection device (Spectra Optia) was analyzed, compared to two established devices (COM.TEC, Cobe Spectra) and evaluated regarding the potential generation of source plasma. Materials and methodsConcurrent plasma collected during leukapheresis was analyzed for residual cell contamination in a prospective study with the new Spectra Optia apheresis device (n=24) and was compared with COM.TEC and Cobe Spectra data (retrospective analysis, n=72). Donor pre-donation counts of platelets were analyzed for their predictive value of contaminating PLTs in plasma harvests. ResultsThe newest apheresis device showed the lowest residual platelet count of the collected concurrent plasma (median 3.50×109/l) independent of pre-donation counts. The other two devices and sets had a higher platelet contamination. The contamination of the plasma with leukocytes was very low (only 2.0% were higher than 0.5×109/l). ConclusionsThis study showed a significant reduction of platelet contamination of the concurrent plasma collected with the new Spectra Optia device. This plasma product with low residual platelets and leukocytes might also be used as plasma for fractionation.

Influence of donor demographics on the platelet yield during plateletpheresis - experience of 1100 procedures at a tertiary-care hospital

Background: Transfusion of plateletpheresis is effective for treating patients with platelet relatedinsufficiencies while limiting recipient’sexposure to platelets from multiple donors. A larger yield isobtained when donor has a greater number of initial platelets and separation done in a shorter time. Theaim of the study was to analyze the effect of various donors and procedure related parameters on the yieldof single donor platelet so that blood donors can be screened effectively in less time.Materials and Methods: One thousand and one hundred plateletpheresis procedures were performed ina tertiary-care super-specialty hospital onFenwal AMICUS machine using closed system kits. Statisticalanalysis was done to establish cause and effect relationship and to find the extent of relationship betweendifferent variables.Results: Height, weight,BMI, platelet count and total leucocyte count had significant correlation withplatelet yield, processing time and blood volume processed while haemoglobin especially in femalescorrelated significantlywith processing time(p<0.0001)and blood volume processed. Rh “negative”donors had shorter processing time than Rh “positive” donors while ABO group did not show anycorrelation with machine variables.Conclusion: Platelet yield correlated positively with pre-donation count, height, weight and BMI.Haemoglobin correlated with processing time and blood volume processed. Optimization of platelet yieldis an emerging issue to identify factors which may help in selecting donors to obtain higher platelet yieldsin shorter time and consequently better clinical outcome.DOI: http://dx.doi.org/10.3126/jpn.v4i7.10292 Journal of Pathology of Nepal (2014) Vol. 4, 525-529

The application of multiparameter reference intervals for pre-donation capillary blood counts: the experience of a single institution

To evaluate a set of reference counts applied to multiparameter pre-counts in blood donors. Analyse the impact of pre-donation counts and specific reference intervals on donors' management. Multiparameter blood counts allow an improved enrollment process of blood donors due to a prompt identification of abnormalities involving haemoglobin (Hb), white blood cells (WBC) and platelets (PLT). Multiple pre-donation capillary counts were applied in the enrollment process of 13,347 consecutive donors. The rate of specific alterations of permanent exclusion and donor readmittance to donations for temporary exclusion had been evaluated, applying a set of multiparameter reference intervals. Alterations involved Hb in 72.55% of cases, mean corpuscular volume (MCV) in 20.99%, total WBC in 9.39%, lymphocytes in 7.55% and PLT in 6.07%. Among donors with initial alterations (543; 4.06%), 12.70% were readmitted to donations within 15 days, 14.36% had permanent exclusion, 36.83% underwent prompt supplementation treatment and 36.09% were lost at follow-up or refused treatments. The systematic use of blood count reference intervals and pre-donation multiparameter blood counts allowed prompt identification of WBC, PLT and MCV alterations, readmittance within 15 days of 12.70% of initially excluded donors and contributed to prompt management of supplement deficiency.

Evaluation of the analytical performances of a portable, 18-parameter hemometric system using capillary blood samples for blood donor enrolment

Blood donor enrolment process is frequently based on the sole capillary haemoglobin (Hb) evaluation while platelet donors by apheresis also requires platelet (Plt) count. The 'sole Hb' approach prevents a complete donor evaluation and does not allow Plt donor enrolment. To extend blood counts before donations, we evaluated the performances of a multiparametric counter using capillary blood. The ABX Micros 60 (Micros 60) blood analyzer was employed on capillary blood and compared with venous counts by a reference counter (Coulter AcT 5diff) in a first series of 416 donors and in a second series of 136, after a 3-month period of routine use of this study counter. An average of 50 microl of capillary blood was collected whose 10 microl had been aspirated by Micros 60. High correlations were found between capillary counts using Micros 60 and venous counts using the reference counter. Mean Plt counts differed of 37 x 10(9)/l less for capillary approach in the first series of comparisons, but decreased to 10 x 10(9)/l less in the second series due to a greater expertise of operators in capillary sampling. All other parameters were accurate and never reached clinical relevance albeit they showed statistically significant differences. Data on Micros 60 demonstrated that capillary predonation counts may represent a feasible and effective approach to realize an accurate enrolment process of blood and Plt donors.

Automated CD14+ monocyte collection with the autoMNC program of the COM.TEC cell separator

The standard mononuclear cell (MNC) program of the COM.TEC device (Fresenius HemoCare GmbH) showed excellent collection efficiency of CD14+ monocytes. A major disadvantage was high content of residual cells in MNC harvests, which could influence dendritic cell (DC) culture. The autoMNC program (COM.TEC) was compared with the standard MNC program (n = 12). Additionally, two cycle volumes (300 mL vs. 450 mL, n = 19) were compared (standard MNC program). Samples were assayed for white blood cells (WBCs), red blood cells (RBCs), granulocytes (PMNs), hematocrit, and platelets (PLTs) on an automated blood cell counter (Sysmex K 4500, TAO Medical). CD14+ cells were analyzed by flow cytometry (FACSCalibur, BD). The autoMNC program produced 1.33 x 10(9) +/- 0.36 x 10(9) CD14+ cells, 5.60 x 10(11) +/- 0.97 x 10(11) PLTs, and 1.43 x 10(11) +/- 0.37 x 10(11) RBCs. Compared to the standard MNC program, significantly higher PLT yields but lower RBC yields and product volume were harvested. Increasing the CV from 300 to 450 mL dropped the product volume, residual PLTs, and RBCs significantly, whereas WBC and monocyte yields did not change. The WBC predonation counts of donors correlated significantly with monocyte yields. The autoMNC program reduced the buffy coat (BC) volume and RBC yields in products compared to the standard MNC program. Increasing the CV (standard MNC program) reduced residual PLTs, RBCs, and the BC volume of MNC harvests. The donor WBC predonation count was a good predictor for the monocyte yield of products.

Mononuclear cell variability and recruitment in non‐cytokine‐stimulated donors after serial 10‐liter leukapheresis procedures

We introduced monitoring of mononuclear cell (MNC) counts to obtain enhanced donor control and a stable quality of MNC products, because there are limited data available about blood donors after serial leukapheresis (LP) procedures. In a prospective paired study, 13 male healthy blood donors underwent 10-L LP procedures performed on two apheresis devices by use of two MNC program settings (COBE Spectra, Gambro BCT, SF 250 vs. SF 500; and AS.TEC 204, Fresenius Hemocare, CP 129 vs. CP 194). Donors' pre- and postdonation MNC counts were analyzed by fluorescence-activated cell sorting. After each 10-L LP procedure, a transient decline (p < 0.05) of CD14+ monocyte and platelet counts appeared in donors. Loss of donors' CD3+ T cells, CD19+ B cells, and CD16+56+ natural killer (NK) cells during MNC collection was partly compensated by cell recruitment. The MNC recruitment factor (RF) seems to be higher with high-yield MNC program settings. Negative correlations (p < 0.01) were noticed between predonation counts and RFs of CD3+ T cells and CD16+56+ NK cells. Four serial 10-L LP procedures did not result in long lasting MNC depletion for donors. MNC recruitment seems to depend on MNC program settings and collected cell yields. Low MNC counts could result in high cell recruitment that may contribute to stable collection results to some degree. Nevertheless, there seems to be a considerable individual variation of MNC recruitment in donors that should be investigated in more detail.

Repeat plateletpheresis: the effects on the donor and the yield.

Requirements for HLA ot otherwise matched single-donor platelets may sometimes require repeat plateletpheresis of an individual donor. AABB standards permit the repeat collection of platelets by plateletpheresis of a single donor at 48-hour intervals, whereas recent recommendations from England state that a donor should not donate platelets more often than 12 times a year. To assess the effects of repeat plateletpheresis on the donor, we have studied the hematological indices and the product yields following every other day plateletpheresis of 13 normal donors who gave a total of 10 times during 22 days. The platelet count decreased in every case, with the lowest values reached at the third donation (day 5). The pre-donation count averaged 225 +/- 53 x 10(9)/l decreasing to 174 +/- 27 x 10(9)/l at the time of the 3rd donation then increasing by the 6th donation to 198 +/- 46 x 10(9)/l. The yield in the product decreased from 3.2 +/- 1.3 x 10(11) on day 1 to 2.6 +/- 0.8 x 10(11) for the third donation, returning thereafter to higher values. In spite of the expected and apparent stimulation of platelet production through feedback, the counts did not rebound above starting levels indicating a basic homeostatic mechanism. The donor WBC showed minimal changes during the study period, however there was a significant increase in the total number of lymphocytes by the 3rd procedure; this was corrected by the fifth procedure. The absolute number and ratio of T4 (helper) and T8 (suppressor) lymphocytes did not change.(ABSTRACT TRUNCATED AT 250 WORDS)

Repeat Plateletpheresis: The Effects on the Donor and the Yield

Requirements for HLA ot otherwise matched single-donor platelets may sometimes require repeat plateletpheresis of an individual donor. AABB standards permit the repeat collection of platelets by plateletpheresis of a single donor at 48-hour intervals, whereas recent recommendations from England state that a donor should not donate platelets more often than 12 times a year. To assess the effects of repeat plateletpheresis on the donor, we have studied the hematological indices and the product yields following every other day plateletpheresis of 13 normal donors who gave a total of 10 times during 22 days. The platelet count decreased in every case, with the lowest values reached at the third donation (day 5). The pre-donation count averaged 225±53 × 109/1 decreasing to 174±27 × 109/1 at the time of the 3rd donation then increasing by the 6th donation to 198±46 × 109/1. The yield in the product decreased from 3.2±1.3 × 1011 on day 1 to 2.6±0.8 × 1011 for the third donation, returning thereafter to higher values. In spite of the expected and apparent stimulation of platelet production through feedback, the counts did not rebound above starting levels indicating a basic homeostatic mechanism. The donor WBC showed minimal changes during the study period, however there was a significant increase in the total number of lymphocytes by the 3rd procedure; this was corrected by the fifth procedure. The absolute number and ratio of T4 (helper) and T8 (suppressor) lymphocytes did not change. The results show the relative safety and efficacy of repeat plateletpheresis procedures when a single donor is committed to a maintenance regime for a designated patient.