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PubMed1991

Efficacy and safety of Fenwal CS-3000 plateletpheresis performed at a rapid donor blood flow rate: rapid plateletpheresis with Fenwal CS-3000.

Results of 3,214 plateletpheresis procedures, using the Fenwal CS-3000 cell separator, were reviewed to determine the effects on performance when the donor blood flow rate was increased by 30% (i.e., to 65 ml/min instead of 50 ml/min). Ninety-two percent (2,962 of 3,214) of procedures completed the rapid flow protocol, and results were compared with those reported by others using the more conventional blood flow rates of 32-55 ml/min. When the rapid flow procedure was used, mean platelet yields (4.07 x 10(11)) and leukocyte contamination (2.65 x 10(8)) were satisfactory, and major donor reactions were infrequent (0.6% of procedures). Thus, CS-3000 plateletpheresis can be performed at a relatively rapid, donor blood flow rate of 65 ml/min to shorten the procedure and make it more appealing to donors.

Blood Flow Velocity↗
PubMed1999

Safety issues of plateletpheresis: comparison of the effects of two cell separators on the activation of coagulation, fibrinolysis, and neutrophils and on the formation of neutrophil-platelet aggregates.

BACKGROUND: Although many donors undergo repeated plateletpheresis, data on the consequences of plateletpheresis for the donor's health remain scarce. Thus, the effect of plateletpheresis on the activation of coagulation, fibrinolysis, and neutrophils was investigated. STUDY DESIGN AND METHODS: Part 1: Sixteen healthy men were randomly assigned to undergo plateletpheresis on a cell separator (AMICUS, Fenwal Baxter; or MCS 3p, Haemonetics). The effects of plateletpheresis on plasma levels of prothrombin fragment (F(1+2)), D-dimer, plasmin-plasmin inhibitor (PPI) complexes, and plasminogen activator inhibitor (PAI-1); on the activation of neutrophils (% L-selectin+); and on the frequency of platelet-neutrophil aggregates (% CD41+ neutrophils) were compared. Part 2: Ten healthy men received infusions of ACD-A and placebo without apheresis in a randomized, double-blind crossover study to control for the pharmacologic effects of citrate. RESULTS: Part 1: No change in F(1+2) occurred (p>0.05), which indicated that plateletpheresis did not enhance coagulation. Levels of D-dimer, PPI, and PAI-1 decreased over time on the AMICUS (p<0.001). Plateletpheresis did not activate neutrophils (p>0.05), but it decreased the percentage of CD41+ neutrophils (p<0.003). An approximately 80-percent drop in mononuclear cells was observed in the extracorporeal circulation of the AMICUS (p<0.001 vs. baseline and p = 0.005 vs. MCS 3p), and circulating lymphocyte and monocyte counts decreased concomitantly. Part 2: Infusion of ACD-A slightly decreased D-dimer levels (p<0.05), and both infusions decreased the circulating lymphocyte counts. CONCLUSION: Plateletpheresis can be regarded as safe with respect to the activation of coagulation or neutrophils. The consequences for the donor's health of the decrease in D-dimer, PPI, and PAI-1 may deserve further investigation.

Adult↗
PubMed2005

The effect of continuous-flow automated plateletpheresis on fibrinolytic activity of donor plasma.

Blood circulating in extracorporeal circuit of the apheresis sets has a contact with an artificial surface. The data on the influence of plateletpheresis on fibrinolytic activity are very limited and difficult to interpret. The aim of our study was to estimate the effect of plateletpheresis on the activation of fibrinolysis. Plateletpheresis was performed in 17 healthy blood donors using continuous-flow cell separator COM.TEC (Fresenius, Bad Homburg, Germany). Before and after plateletpheresis, blood samples were taken and markers of fibrinolysis (PAP, t-PA, PAI-1) as well as factor XII activity have been measured. We observed statistically significant decrease in t-PA and factor XII activities after plateletpheresis. There were no significant changes in concentrations of t-PA, PAI-1 and PAP as well as PAI-1 activity after plateletpheresis. Plateletpheresis performed by COM.TEC cell separator has very little, if any, effect on the activation of fibrinolysis. The mechanism of the inhibition of t-PA activity needs further investigations.

Automation↗
PubMed2000

Single automated donor plateletpheresis increases the plasma level of proinflammatory cytokine tumor necrosis factor-alpha which does not associate with endothelial release markers von Willebrand factor and fibronectin.

The effect of plateletpheresis on endothelium, which has strong effects on blood coagulation, fibrinolysis and platelet function, is not known. Activation of leukocytes and subsequent generation of proinflammatory cytokines during the extracorporeal circulation may activate the endothelium. To test this hypothesis we measured plasma levels of tumor necrosis factor (TNF)-alpha as a prototype of the proinflammatory cytokines, and von Willebrand factor (vWF) and fibronectin as endothelial release/damage markers before and after a single plateletpheresis procedure on an intermittent-flow machine Haemonetics MCS 3p in 17 healthy donors. We found a significant increase in median plasma level of TNF-alpha following plateletpheresis (3.5 vs 26.5 pg/ml, P=0.02). Such increases in vWF and fibronectin were not observed. The increase in plasma TNF-alpha indicates that a single plateletpheresis procedure causes leukocyte activation which does not seemingly impair endothelial cell function. The relation of plateletpheresis-induced proinflammatory cytokine release to some adverse effects observed in both donors and recipients, and the effect of repeated plateletpheresis on endothelium deserve further studies.

Adult↗
PubMed2003

Donor exposure to the plasticizer di(2-ethylhexyl)phthalate during plateletpheresis.

BACKGROUND: Di(2-ethylhexyl)phthalate (DEHP) is a plasticizer that is contained in most PVC devices, including apheresis disposables. Because DEHP can be extracted from apheresis disposables as the blood passes through the apheresis device, DEHP exposure was determined in healthy donors undergoing plateletpheresis performed with commercially available apheresis systems. STUDY DESIGN AND METHODS: The study population consisted of 36 healthy PLT donors undergoing plateletpheresis with either continuous or discontinuous apheresis devices. Serum concentrations of DEHP were determined from peripheral blood obtained before and after plateletpheresis, with gas chromatography-mass spectroscopy. RESULTS: Plateletpheresis performed with standard collection disposables resulted in a median increase of 232 percent of serum DEHP compared to levels before apheresis, corresponding to a total amount of DEHP exposed during a single apheresis of a median of 6.46 (range, 1.8-20.3) microg per kg of body weight. Endogenous levels of triglycerides showed a positive correlation with the amount of DEHP released. Increase in serum DEHP was short-term as serum DEHP rapidly returned to levels obtained before apheresis within 3 hours after completion of the apheresis course. Donor exposure to DEHP led to no variation in liver cell function within 48 hours after plateletpheresis. CONCLUSION: Commercial plateletpheresis disposables release considerable amounts of DEHP during the apheresis procedure, but the total dose of DEHP retained by the donor is within the normal range of DEHP exposure of the general population.

Blood Donors↗
PubMed1987

The effect of plateletpheresis on the Fenwal CS-3000 on donor platelet counts.

To evaluate the risk of significant plateletpheresis-induced thrombocytopenia in normal volunteer donors undergoing plateletpheresis less frequently than every 56 days and to help understand factors influencing platelet yield in these donors, pre- and postapheresis platelet counts (X 10(3)/microliter) and platelet yields were analyzed from 916 plateletpheresis procedures (Fenwal CS-3000) on 607 donors (405 men, 202 women). The mean preapheresis platelet count was 265 +/- 59 (SD) (range 155-650) (men 256 +/- 55 [170-444]; women 284 +/- 65 [155-650]; P less than .001, t-test). After an average platelet yield of 4.08 X 10(11), the mean postplatelet count was 185 +/- 46 (range 72-420) (men 184 +/- 42 [80-345]; women 194 +/- 52 [72-500]; P less than 0.1). The percent decrease in platelet count (mean 29.4 +/- 13, range -28.1-65.5) had positive correlations with platelet yield (P less than .01, r = 0.10), predonation platelet count (P less than .001, r = 0.29), and age (P less than .01, r = .10) and a negative correlation with weight (P less than .001, r = 0.18) Both the percent decrease and platelet yield were significantly higher in women than in men (P less than .001, t-test), and platelet yield was best predicted by preapheresis platelet count in both sexes (r = 0.65). The effects of plateletpheresis on donor platelet count thus vary widely among donors. Although a decrease of greater than 50% was not a rare event (5.9% of all procedures), in only three instances (0.3%) was the actual postapheresis platelet count below 100 (72, 94, 95). Thus, plateletpheresis in normal donors appears unlikely to produce clinically significant thrombocytopenia immediately after apheresis.

Adult↗
PubMed1998

Increase in endogenous thrombopoietin in healthy donors after automated plateletpheresis.

BACKGROUND: Thrombopoietin (TPO) is a key cytokine involved in the regulation of megakaryocytopoiesis and platelet production. The aim of the present study was to test whether platelet donation is associated with changes in the serum TPO levels in healthy donors undergoing plateletpheresis. STUDY DESIGN AND METHODS: The study group consisted of 23 healthy donors undergoing single-donor plateletpheresis for the first time. Serum TPO levels and platelet counts were determined before platelet collection, at the end of apheresis, and for 4 days thereafter. Serum TPO levels were determined by a TPO-specific enzyme-linked immunosorbent assay. RESULTS: In relationship to platelet donation, serum TPO levels showed a temporary increase from baseline levels of 69.2 +/- 7.1 pg per mL to 117 +/- 6.8 pg per mL 2 days after plateletpheresis (p < 0.05). Further evaluation revealed a decline in serum TPO levels as platelet counts increased. Female donors showed a delayed normalization of circulating platelet numbers and serum TPO levels as compared to male donors. There was no significant correlation between serum TPO levels and the absolute platelet number during normalization of the donors' platelet counts after plateletpheresis. CONCLUSION: Single-donor plateletpheresis results in a temporary increase in serum TPO levels in healthy platelet donors, which may be part of a compensatory response-boosting megakaryocytopoiesis after platelet collection.

Blood Donors↗
PubMed2001

Sustained decreases in platelet count associated with multiple, regular plateletpheresis donations.

BACKGROUND: Transient but significant decreases in platelet counts have been documented to occur in donors undergoing single and serial short-term plateletpheresis collections. The effect of long-term regular plateletpheresis on donor platelet counts has not been characterized. STUDY DESIGN AND METHODS: A retrospective study was performed to evaluate the effects of long-term regular plateletpheresis donation on donor platelet counts. A computerized database containing records of 11,464 apheresis collections from 939 donors over a 4-year period was queried for serial preapheresis platelet counts. Donors were categorized by sex, age, and cumulative number of donations. The average difference in platelet counts (mDeltaPC) between each donor's first and last platelet count during this period was calculated for each category. A subgroup of frequent donors was selected for analysis of mDeltaPC, using the baseline platelet count obtained before the first plateletpheresis procedure. RESULTS: A significant and sustained decrease in platelet count was identified for all donation frequency categories. The frequency of donation correlated directly with decrease in platelet count for all but the highest-frequency donation group, in which deferrals for low platelet count blunted the extent of the mDeltaPC. A mean decrease of 40,000 per microL from baseline occurred in the frequent-donor subgroup. A total of 84 donors (9%) were deferred for low platelet count. The majority returned to donate successfully after temporary deferral. CONCLUSIONS: Regular plateletpheresis donors develop sustained decreases in platelet count. However, clinically significant thrombocytopenia is unusual when rigorous ongoing review and prudent deferral policies are established and followed.

Adult↗
PubMed2003

Randomized placebo-controlled study of oral calcium carbonate supplementation in plateletpheresis: II. Metabolic effects.

BACKGROUND: The metabolic effects of oral calcium (Ca) supplementation during plateletpheresis were evaluated in a randomized, placebo-controlled trial. STUDY DESIGN AND METHODS: Twenty-three donors underwent four plateletpheresis procedures each, receiving in random order, elemental Ca (Ca) 1 or 2 g orally, or a corresponding placebo, 30 minutes before donation. Ten of these donors underwent a fifth procedure using a 4-g Ca dose. All procedures were performed at a fixed citrate infusion rate of 1.5 mg per kg per minute. RESULTS: Oral Ca induced dose-sensitive changes in parathyroid hormone (iPTH), total (tCa), and ionized (iCa) calcium levels. Compared to placebo, the greatest improvement in tCa and iCa levels occurred after the 2-g Ca dose (tCa of 73, 89, and 25% above placebo levels at 60 min, using 1, 2, and 4 g of oral Ca, respectively). Twenty-four hours after apheresis, serum tCa and iCa levels were higher, and iPTH levels lower, in donors who received oral Ca rather than placebo. Marked increases in urinary Ca and magnesium (Mg) excretion occurred at the completion of apheresis, were unaffected by Ca dose, and returned to baseline within 24 hours. Plateletpheresis also induced significant changes in serum alkaline phosphatase, 1,25-dihydroxyvitamin D, and osteocalcin levels immediately and at 24 hours after apheresis. CONCLUSION: Plateletpheresis induces marked acute metabolic effects, with sustained changes evident up to 24 hours after the completion of apheresis. Oral Ca supplementation exerts a significant but clinically modest impact on selected laboratory variables associated with these effects. Further studies are indicated to examine the long-term impact of plateletpheresis, with or without Ca supplementation, on donor Ca balance and bone density.

Administration, Oral↗
PubMed1997

Automated plateletpheresis does not cause an increase in platelet activation in volunteer donors.

Activation of platelets during collection and storage has been implicated as a major cause of the platelet storage lesion. In this study, we investigated the effect of an automated plateletpheresis procedure on the in vivo platelet activation in 20 volunteer donors. Peripheral blood samples were collected immediately before and after plateletpheresis on the Haemonetics V50 Blood Cell Separator. Activation of platelets was determined by quantitating the amount of platelet P-selectin (CD62) expression using a whole blood method on flow cytometry. Adenosine diphosphate (ADP), collagen, and ristocetin induced platelet aggregations were also measured on a whole blood impedance aggregometer. Plateletpheresis caused a significant decrease in the CD62-positive platelet percentage and aggregation responses to 3 agonists. We concluded that the plateletpheresis procedure did not cause an increase in platelet activation in donors. Further studies are required to elucidate whether activated platelets are collected during the procedure or removed from the circulation of the donor and replaced by resting platelets, activated platelets bind to leukocytes or endothelial cells, and the plateletpheresis procedure is a powerful stimulus for platelet activation.

Adult↗
PubMed2006

Successful removal of Chlamydia pneumoniae from plateletpheresis products collected using automated leukoreduction hemapheresis techniques.

Chlamydia pneumoniae (Cp) is an obligate intracellular pathogen associated with a variety of maladies. Best known for its involvement in community-acquired pneumonia outbreaks; the potential role of Cp in diverse illnesses is a topic of increasing interest and investigation. Previous studies suggested that white blood cells from normal blood donors harboring this agent may be eliminated through leukoreduction by filtration. Here we examine the ability and efficacy of apheresis-related leukoreduction for its effect on the carriage and potential infectivity of these organisms in the preparation of platelet products. Matched pre-apheresis peripheral blood (PB) samples and product samples obtained from healthy plateletpheresis donors were analyzed for the presence and potential infectivity of Cp organisms by direct smear inspection and tissue culture techniques. Antibody seroreactivity directed towards the organism was assessed using a solid phase immunoassay. Forty-eight percent of the donor blood samples exhibited elevated anti-Cp antibody titers (> or =200). Specimens from 31 (27%) and 34 (30%) of 115 plateletpheresis donors were positive for the presence of Cp organisms in their pre-apheresis PB samples when analyzed by direct smear examination and culture, respectively. Examination of the 115 post-leukodepleted plateletpheresis product samples revealed only two (1.7%) and one (0.009%) product(s) to be smear-positive and culture-positive, respectively. Certain plateletpheresis donors may harbor infectious Cp organisms in circulating WBC. Collections from such donors of apheresis platelet products using standard apheresis leukoreduction strategies appear successful in markedly decreasing or eliminating the organisms found in the final products.

Adult↗
PubMed1993

Preoperative plateletpheresis does not reduce blood loss during cardiac surgery.

Acute preoperative plateletpheresis has been reported to be effective in reducing blood loss and blood component transfusion while improving haematological profiles in patients undergoing open-heart surgery. However, in these studies, the concomitant use of cell saver techniques may have been responsible for the beneficial effects because they remove free haemoglobin and activated procoagulants and, therefore, could mask the deleterious effects of combined plateletpheresis and cardiopulmonary bypass (CPB). In the present study, 40 patients undergoing primary myocardial revascularization were randomly divided into two groups: a control group without plateletpheresis performed, and a second group in which preoperative platelet-rich plasma 10 ml.kg-1 (PRP group) was collected and later reinfused after reversal of heparin. Standardized surgery, anaesthesia and CPB without concomitant cell saver techniques were employed. In the PRP group, blood transfusion was reduced (1.5 +/- 1.3 vs 2.4 +/- 1.3 units, P < 0.05) but this was accompanied by lower postoperative haemoglobin concentrations. There were no differences in blood loss (992.6 +/- 327.4 vs 889.6 +/- 343.7 ml), fresh frozen plasma (2/19 vs 3/20 patients) or platelet requirements (1/19 vs 1/20 patients). Reinfusion of autologous PRP did not improve platelet count and function, nor tests of coagulation. Fibrinogen concentrations were lower in the PRP group on the operative day (P < 0.05), suggesting increased fibrinogen consumption; and more patients in the PRP group had low haptoglobin levels during CPB (8/19 vs 0/20 patients, P < 0.005), which indicated greater haemolysis in this group. We conclude that acute preoperative plateletpheresis offers no advantage in haemostasis during elective primary myocardial revascularization surgery.

Anesthesia, General↗
PubMed2001

Kinetics of CFU-Mk after automated plateletpheresis.

BACKGROUND AND OBJECTIVES: Platelet count, thrombopoetin (TPO) level and the compartment of megakaryocyte progenitor cells (CFU-Mk) are major determinants in the regulation of thrombopoiesis. The aim of this study was to investigate the potential changes in the compartment of CFU-Mk and their correlation with serum TPO levels and platelet count after plateletpheresis. MATERIALS AND METHODS: Twelve healthy individuals were randomly assigned to undergo single-donor plateletpheresis. A collagen-based in vitro culture system was used to determine the number of peripheral blood (PB) CFU-Mk before and after donation and on days 1, 4 and 7 thereafter. TPO levels were measured by a specific enzyme-linked immunosorbent assay and whole blood counts were performed using an automated cell counter. RESULTS: The pre-apheresis platelet count (mean +/- SEM: 276 +/- 13 x 10(9)/l) decreased after plateletpheresis to a nadir of 194 +/- 8 x 10(9)/l (P < 0.001), showed a gradual increase on days 1 and 4, and reached pre-apheresis values by day 7 (280 +/- 11). The serum TPO levels were found to be significantly increased on days 1 and 7 as compared to baseline levels (baseline value 103.3 +/- 18.5 pg/ml versus day-1 value 135.8 +/- 25.8 pg/ml and day-7 value 132 +/- 30.19 pg/ml; P < 0.03 and P < 0.03, respectively). The numbers of CFU-Mk in PB were significantly elevated on day 4 only (125 +/- 21 colonies/ml of PB versus pre-apheresis values of 68 +/- 18 colonies/ml of PB, P < 0.005). CONCLUSIONS: These findings suggest that platelet loss during plateletpheresis affects thrombopoiesis at the progenitor cell level, probably through alterations in TPO plasma concentrations.

Blood Cell Count↗
PubMed1993

Strategies to recruit plateletpheresis donors from a registry of HLA-typed, unrelated, bone marrow donors.

Rising demand for single-donor platelet components--from random donors, to maintain platelet inventories, or from HLA-compatible donors, to support alloimmune platelet-refractory patients--necessitated increasing the size of a community plateletpheresis donor registry. This study compares two strategies for recruiting whole-blood donors into a plateletpheresis program. The whole-blood donors who were asked to participate in this study had recently joined an unrelated bone marrow donor registry and had been HLA-typed as part of that process. An in-person recruitment strategy, which was time-intensive for the apheresis donor coordinator, served as the standard. A by-mail strategy involved the mailing of recruitment materials to marrow-donor registry participants. Marrow-donor registry participants were approached about apheresis participation after they had indicated an interest in the plateletpheresis program by returning a tear-off section of an informational brochure that was sent to them along with their marrow-donor registry materials. A total of 852 marrow-donor registry participants were randomly assigned to one of two recruitment strategies, and the recruitment rates were the same (46%) for both methods. In addition, levels of apheresis participation and attrition rates of donors recruited by either strategy were comparable. Thus, the simple strategy of mailing information about a plateletpheresis program is a very cost-effective method of recruiting donors.

Blood Donors↗
PubMed1998

Measurement of the levels of reticulated platelets after plateletpheresis to monitor activity of thrombopoiesis.

BACKGROUND: Little is known about the effects of long-term plateletpheresis on the donors' health. The aim of this study was to examine the effect of plateletpheresis on the time course of reticulated platelet counts as an estimate for thrombopoiesis. STUDY DESIGN AND METHODS: The effect of moderate platelet depletion on the thrombopoietic capacity was evaluated prospectively by the measurement of reticulated platelets before and after plateletpheresis and on the following 4 days. Donors undergoing plateletpheresis for the first time were compared to those donating platelets every other week for more than 18 months. RESULTS: The median levels of reticulated platelets were significantly lower in frequent donors than in new donors. In new donors, there was a transient increase in the median levels of reticulated platelets on Day 3 after apheresis, and baseline values were reached again on Day 4. On the contrary, in repeat donors, there was a sustained rise in the percentage of reticulated platelets from Days 1 through 4. However, this increase in reticulated platelet counts was still less than that seen in new donors. There was no difference in the peripheral blood platelet counts in the two groups at any time point. CONCLUSION: These findings suggest that repeat platelet donation might lead to a relative exhaustion of thrombopoiesis, as evidenced by the low levels of reticulated platelets exhibited by repeat donors. The reticulated platelet count can be used to monitor the thrombopoietic capacity of long-term platelet donors.

Adult↗
PubMed1999

Platelet surface p-selectin, platelet-granulocyte heterotypic aggregates, and plasma-soluble p-selectin during plateletpheresis.

BACKGROUND: Plateletpheresis components have been shown to contain p-selectin-positive platelets after collection and storage. P-selectin mediates binding of activated platelets to granulocytes and monocytes. This study was undertaken to assess platelet activation, granulocyte activation, platelet-granulocyte heterotypic aggregate formation, and the plasma-soluble p-selectin level during plateletpheresis performed on a particular instrument (MCS+, Haemonetics). STUDY DESIGN AND METHODS: Flow cytometry was used to assay platelet surface p-selectin, granulocyte iC3b receptor, and platelet-granulocyte aggregates in the platelet component, residual blood in the disposable polycarbonate bowl of the MCS+, and in the donor blood with and without the addition of in vitro agonists before, during, and after plateletpheresis. The plasma-soluble p-selectin levels in the platelet component, disposable bowl, and donor venous blood were measured by an enzyme-linked immunosorbent assay. RESULTS: Levels of p-selectin-positive platelets, activated granulocytes, and platelet-granulocyte aggregates were greater in the disposable bowl than in the preapheresis donor blood. Levels of p-selectin-positive platelets, activated granulocytes, and platelet-granulocyte aggregates in the postapheresis donor blood were similar to those in the preapheresis donor blood. The platelet components contained no activated granulocytes or detectable platelet-granulocyte heterotypic aggregates, and only about 10-percent activated platelets. The plasma-soluble p-selectin level in the platelet component was significantly greater than that in the preapheresis donor blood, the residual blood in the disposable bowl, or the postapheresis donor blood. CONCLUSIONS: Measurements of platelet surface p-selectin, platelet-granulocyte heterotypic aggregates, and plasma-soluble p-selectin can be used to detect platelet activation during plateletpheresis.

Antibodies, Heterophile↗
PubMed2001

Generation of reticulated platelets in response to whole blood donation or plateletpheresis.

BACKGROUND: There are few reports about thrombopoietic responses in whole blood (WB) and platelet-pheresis donors. This study compares the thrombopoietic responses of such donors and their platelet values. STUDY DESIGN AND METHODS: The effect of WB donation or selective platelet loss (plateletpheresis) was evaluated prospectively. WB and platelet donor samples before donation and for 7 days thereafter were assessed for platelet count, mean platelet volume, and platelet reticulocytes. RESULTS: Reticulated platelets appeared in the circulation of plateletpheresis donors by 24 hours. The proportion of reticulated platelets was highest on Day 2, and above-normal levels of reticulated platelets persisted until Day 7. The mean platelet volume was high on Days 2 and 3, which corresponded with the appearance of reticulated platelets. After plateletpheresis, platelet counts were higher than could be accounted for by new platelets, which suggested the release of sequestered platelets. WB donors manifested no changes in platelet counts but had a peak of circulating platelet reticulocytes 2 days after the donation. CONCLUSION: The thrombopoietic peak in WB and plateletpheresis donors occurs 2 days after donation, and the response level is related to the amount of platelets lost. The impact of platelet loss on the number of circulating platelets is modulated by the release of platelets from the spleen.

Benzothiazoles↗
PubMed2005

Calcium and magnesium levels during automated plateletpheresis in normal donors.

It is well known that citrate induces ionized hypocalcaemia by the chelating effect during plateletpheresis. However, the kinetics of serum magnesium (Mg) ions has not been well documented. We, therefore, evaluated biochemical changes in healthy donors during plateletpheresis procedure. Ten healthy donors underwent plateletpheresis on continuous cell separator (CS3000, Baxter, Round Lake, IL, USA) and 10 on intermittent flow cell separator (MCS 3p, Hemonetics, Braintree, MA, USA). Serum levels of total and ionized calcium (tCa and iCa, respectively) and Mg (tMg and iMg, respectively) were measured before, during and after the procedures. Although, the fall in tCa (from 2.62 +/- 0.12 to 2.36 +/- 0.12 mmol L(-1)) and tMg (from 0.89 +/- 0.01 to 0.79 +/- 0.01 mmol L(-1)) was modest and not significant; drop in iCa (from 1.33 +/- 0.1 to 0.84 +/- 0.1 mmol L(-1)) and iMg (from 0.53 +/- 0.01 to 0.35 +/- 0.1 mmol L(-1)) was statistically significant (P < 0.001). There were no significant differences observed between the CS3000 and MCS 3p cell separators regarding the fall in Ca and Mg. None of the donors experienced any adverse reactions during the procedures. In the study, an acute ionized hypocalcaemia and hypomagnesaemia have been observed after the plateletpheresis; therefore, measurement of both the ions may be monitored. However, there is no justification for prophylactic supplementation of either of these elements.

Blood Donors↗