Citrate anticoagulation: Are blood donors donating bone?

Association of regular plasmapheresis donation with serum protein and electrolyte levels: a multicentre cross-sectional study in China

BACKGROUND

China's plasmapheresis donation policy differs from that of Western countries. The association between regular plasmapheresis donation and donor health in China is still unknown.

OBJECTIVES

To investigate the association of regular plasmapheresis donation with serum protein and electrolyte levels and provide scientific evidence for policy improvement.

DESIGN

Multicentre cross-sectional study.

SETTING AND PARTICIPANTS

A total of 767 regular and 726 new donors from the provinces of Sichuan, Hunan, Henan and Yunnan were recruited from September 2021 to October 2022.

PRIMARY AND SECONDARY OUTCOME MEASURES

Our primary outcome focused on measuring the levels of serum protein and electrolyte levels, including total serum protein (TSP), IgG, albumin (Alb), haemoglobin (Hb), calcium, potassium (K+) and magnesium (Mg2+). The secondary outcome assessed their abnormal rates.

RESULTS

Male and female donors in the high donation frequency group (>16 donations per year) exhibited lower IgG levels compared with new donors (p=0.008 for male donors and p=0.007 for female donors). Additionally, female donors with high donation frequency and a high total number of lifetime donations (>100 donations) had significantly lower Hb concentrations than new donors. However, no significant changes were observed in TSP, Alb, calcium, K+ and Mg2+ levels. There were also no statistically significant differences in the rates of abnormal protein and electrolyte values below the respective threshold levels between new and regular donors.

CONCLUSIONS

Plasmapheresis donation is not associated with an increased risk of abnormalities in the analysed parameters. However, the results provide preliminary evidence supporting the routine inclusion of IgG screening for donors, as plasmapheresis donation is associated with a decrease in IgG levels. Particular attention should be paid to the Hb levels of female donors, especially those who donate frequently. Testing of TSP at each donation may not be necessary.

How to explain the beneficial effects of platelet-rich plasma

Platelet-rich plasma (PRP) is the platelet and leukocyte-containing plasmatic fraction of anticoagulated autologous blood. While evidence supporting the clinical use of PRP in dentistry is low, PRP is widely used in sports medicine, orthopedics, and dermatology. Its beneficial activity is commonly attributed to the growth factors released from platelets accumulating in PRP; however, evidence is indirect and not comprehensive. There is thus a demand to revisit PRP with respect to basic and translational science. This review is to (i) recapitulate protocols and tools to prepare PRP; (ii) to discuss the cellular and molecular composition of PRP with a focus on platelets, leukocytes, and the fibrin-rich extracellular matrix of coagulated plasma; and finally (iii) to discuss potential beneficial effects of PRP on a cellular and molecular level with an outlook on its current use in dentistry and other medical fields.

A donor safety evidence literature review of the short- and long-term effects of plasmapheresis

Many blood establishments are expanding plasmapheresis collection capacity to achieve increasing plasma for fractionation volume targets, driven by immunoglobulin product demand. Some adverse events occur in both apheresis and whole blood collection, such as venepuncture-related trauma and vasovagal reactions. Others are specifically related to the apheresis procedure, such as citrate reactions, haemolysis, infiltration and air embolism. Whilst plasmapheresis procedures are generally well tolerated, theoretical longer term donor health considerations, such as the effects on donor plasma protein levels, bone mineral density, iron deficiency and malignancy also require consideration. An evidence-based framework that supports a safe and sustainable increase in the collection of plasma is essential. Our review demonstrates a lack of high-quality evidence on risks and outcomes specifically in plasmapheresis. Whilst conservative procedural controls and donor harm minimization policies will mitigate risk, high-quality evidence is needed to facilitate practice change that is safe and sustainable and maximizes the potential of individual donor differences.

Alteration in biochemical parameters during plateletpheresis in healthy donors: A compendious analysis

OBJECTIVES

During plateletpheresis, citrate induces hypocalcemia and hypomagnesemia, which are usually transient and self-limiting, but they can lead to significant donor discomfort. The aim of study was to determine the effect of citrate infusion on a multitude of biochemical parameters during plateletpheresis in healthy donors and to correlate changes with adverse donor reactions.

METHODS

The study was conducted on 60 healthy plateletpheresis donors. Blood samples were drawn on three occasions, a baseline pre-donation sample, 30min at start of procedure and 30min post procedure. Heparinized samples were taken to measure ionized calcium and plain samples to measure serum calcium, serum magnesium, parathyroid hormone, total protein and serum albumin.

RESULTS

There was statistically significant decline in mean total calcium (9.27±0.66mg/dl to 8.72±0.87mg/dl) and ionized calcium (3.8±0.51mg/dl to 2.9±0.67mg/dl) from baseline until 30min after the start of procedure respectively. A significant fall in serum magnesium, total protein and serum albumin was observed. The mean parathyroid hormone showed significant increase from baseline levels till at the completion of procedure (19.94±12.1pg/ml to 92.08±36.78pg/ml). If the yield was set constant, there was negative correlation between ACD used and pre-donation platelet count. Majority of adverse donor reactions were hypocalcemic reactions, which were more with Amicus double yield plateletpheresis and were managed with calcium supplementation.

CONCLUSION

Plateletpheresis induces marked reduction in serum calcium and magnesium levels. Moreover, increase in parathyroid hormone levels was significant. In addition, decline in total protein and serum albumin may be a concern in donors also participating in plasmapheresis.

An Observational Cohort Study of the 2-Month Use of Regional Citrate Anticoagulation in Maintenance Hemodialysis Patients with Cerebral Hemorrhage

Background

Regional citrate anticoagulation (RCA) is a recommended anticoagulation alternative for patients at high risk of bleeding while undergoing intermittent hemodialysis. Previous reports implied the risk of citrate application on bone metabolism. It is unclear whether long-term use of RCA is safe for maintenance hemodialysis patients in terms of bone metabolism.

Material/Methods

Seven patients with cerebral hemorrhage were included in the study. Blood samples were collected at baseline and 4 and 8 weeks after treatment. Spent dialysate samples were collected during each mid-week dialysis session, using the partial dialysate collection method. All patients were treated with RCA for 4 to 8 weeks, according to their clinical condition. We assessed bone metabolism-associated parameters, bone turnover markers, and magnesium loss at each dialysis session.

Results

Serum magnesium levels were 1.24±0.13 mmol/L at baseline and significantly decreased to 1.16±0.14 mmol/L after 4 weeks of RCA treatment (P=0.025). Most patients had negative magnesium balance during citrate hemodialysis. Serum total calcium levels did not change significantly after treatment. One bone marker, N-terminal propeptide of type I procollagen (PINP), significantly decreased from 146.07±130.12 mmol/L to 92.42±79.01 mmol/L after citrate treatment (P=0.018). No significant changes were detected in other bone turnover markers.

Conclusions

Relatively long-term RCA treatment may decrease serum magnesium levels due to negative magnesium balance. Bone formation marker PINP seemed to decrease after treatment, while other bone turnover markers did not change significantly. Further investigation is needed to verify the effect of RCA on bone remodeling.

Adverse events associated with donor plateletpheresis: 10 years’ experience from Vojvodina, Serbia

Background/Aim. Plateletpheresis is a medical procedure used for the collection of donor platelets with multiple benefits for patients who will receive apheresis platelets. The procedure takes one hour and is well tolerated by donors. Nevertheless, adverse events may occur during and after the plateletpheresis procedure. The aim was to present one centre experiences in order to determine the incidence and type of adverse events associated with donor plateletpheresis. Methods. A retrospective analysis of adverse events associated with donor plateletpheresis was conducted in the Blood Transfusion Institute of Vojvodina over the period from January 1, 2010 through December 31, 2019. Results. Out of 2073 platelet donors 94.84% were multiple blood donors, predominantly male (98.55%). Adverse events were identified during 180 (8.68%) platelet donations with no statistical significance in occurrence in the first time (10.28%) and repeat donors (8.59%). Mild local reactions related to venous access (42.22%) were the most common adverse events. Generalized symptoms exhibited 16.67% of donors, 26.11% exhibited symptoms related to apheresis - citrate reactions and 15% exhibited those related to other complications. During plateletpheresis occurred 95.55% adverse events and 4.45% after. Conclusion. Donor plateletpheresis is a generally safe procedure, well tolerated by donors. Understanding risk factors for possible occurrence of adverse events provide support for adoption of measures to prevent them.

Putting the spotlight on donation-related risks and donor safety - are we succeeding in protecting donors?

BACKGROUND AND OBJECTIVE

The European consortium project TRANSPOSE (TRANSfusion and transplantation: PrOtection and SElection of donors) aimed to assess and evaluate the risks to donors of Substances of Human Origin (SoHO), and to identify gaps between current donor vigilance systems and perceived risks.

MATERIALS AND METHODS

National and local data from participating organizations on serious and non-serious adverse reactions in donors were collected from 2014 to 2017. Following this, a survey was performed among participants to identify risks not included in the data sets. Finally, participants rated the risks according to severity, level of evidence and prevalence.

RESULTS

Significant discrepancies between anticipated donor risks and the collected data were found. Furthermore, many participants reported that national data on adverse reactions in donors of stem cells, gametes, embryos and tissues were not routinely collected and/or available.

CONCLUSIONS

These findings indicate that there is a need to further develop and standardize donor vigilance in Europe and to include long-term risks to donors, which are currently underreported, ensuring donor health and securing the future supply of SoHO.

Quantitative assessment of the anticoagulant in plasma units collected by plasmapheresis

BACKGROUND

To date, the quantification of the anticoagulant (ACD-A) in plasma units has been based on theoretical calculations. An accurate quantification could help minimize the risks associated with plasmapheresis, given that the total ACD-A used during the procedure is distributed between the donor and the plasma unit. Our aim was to experimentally quantify the volume of ACD-A in units collected by plasmapheresis.

STUDY DESIGN AND METHODS

We used proton nuclear magnetic resonance spectroscopy to measure the ACD-A volume in 295 plasma units collected by the Azienda USL-IRCCS of Reggio Emilia, Italy. We analyzed the determinants of the differences between estimated and measured ACD-A through multivariate regression models.

RESULTS

The experimentally measured ACD-A in plasma units was variable, with 45% of the samples showing a discrepancy of more than 15 mL compared to the manufacturer's estimate. ACD-A was underestimated for higher density of the units (p < 0.0005); a weak association was also observed with triglycerides (underestimated for higher levels, p = 0.015) and sex (overestimated in females, p = 0.008), but our model explained only 35% of the individual variability.

CONCLUSION

The manufacturer's algorithms do not accurately estimate the ACD-A in units collected by plasmapheresis. Donor-related characteristics may affect ACD-A distribution between donor and plasma unit, thereby explaining the discrepancies between estimate and measurement. Errors in the estimate of the ACD-A actually received by donors could hamper studies on dose-response relationship between anticoagulant and adverse reactions. Our work should stimulate research on tailored procedures aimed at minimizing the anticoagulant received by donors and increasing plasmapheresis safety.

Impact of frequent apheresis blood donation on bone density: A prospective, longitudinal, randomized, controlled trial

Background

Blood for transfusion is lifesaving and essential to many elements of modern medical practice. The global blood supply relies on volunteer blood donors. Apheresis is increasingly used to collect blood and requires anticoagulant to prevent extracorporeal coagulation. Citrate, the standard apheresis anticoagulant, chelates ionized calcium with consequent perturbations of serum calcium, parathyroid hormone, vitamin D, and markers of bone remodeling in donors. Cross-sectional studies of bone mineral density (BMD) among apheresis donors exhibit conflicting results.

Methods

The longitudinal, randomized, controlled ALTRUYST trial (NCT02655055) was undertaken to determine whether BMD declined following high frequency apheresis blood donation over 1 year. The study was powered at 80% to detect the primary outcome of a 3% decline in BMD. Subjects new to apheresis agreed to make ≥20 apheresis donations in a one-year period and were randomized to treatment (high frequency apheresis) or control (no apheresis). Dual-energy x-ray absorptiometry was performed before and after participation. Two-sided t-test and multivariable logistic regression were used to assess outcomes.

Findings

Mean lumbar spine BMD did not change during the study among control donors (−0.002 g/cm², 95%CI [−0.020, 0.016], p = 0.78), or among donors in the apheresis arm (mean change = 0.007 g/cm², 95%CI [−0.005, 0.018], p = 0.24). Mean total hip BMD did not change for control donors (mean change = 0.002 g/cm², 95%CI [−0.006, 0.009], p = 0.63) or apheresis donors (−0.004 g/cm², 95%CI [−0.10, 0.002], p = 0.16). Tests for differences in proportions of donors with change in BMD exceeding the least significant change at the lumbar spine in either a positive [8 apheresis (31%), 4 control (27%), p = 0.78] or negative direction [4 apheresis (15%), 5 control (33%)] were statistically non-significant (p = 0.18). Proportional increases [0 apheresis (0%), 1 control (7%), p = 0.18] and decreases [3 apheresis (12%), 1 control (14%)] were also not significantly different at the total hip (p = 0.61).

Interpretation

ALTRUYST is the first longitudinal trial to demonstrate that apheresis blood collection guidelines in the United States adequately protect the skeletal health of male volunteer blood donors.

Funding

Marquette University and the BloodCenter Research Foundation.

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ALTRUYST (NCT02655055) was a prospective RCT.

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It tested if BMD declined following high frequency apheresis blood donation.

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High frequency apheresis blood donation did not affect lumbar spine BMD.

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High frequency apheresis blood donation did not affect total hip BMD.

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High frequency apheresis blood donation did not affect trabecular bone score.

Epidemiology of donors and recipients: lessons from the SCANDAT database

With the development of several 'vein-to-vein' databases, which capture data on the entire donor-recipient continuum and link this data to health outcomes, there has been an increasing number of studies investigating the health effects of all aspects of the practice of transfusion medicine. The Scandinavian Donations and Transfusions (SCANDAT) database is one of several such databases, which includes all electronically available data on blood donors, donations and transfusions since the late 1960s in Sweden and the early 1980s in Denmark. The SCANDAT database has been used to characterise disease occurrence among blood donors and transfused patients, as well as to investigate possible health effects of blood donations, aspects of transfusion care and possible transfusion transmission of disease. Recent publications include studies on recipient mortality associated with the storage lesion, studies on the effects of donor demographics on patient mortality and health effects of frequent blood donation. Although this research approach is clearly very powerful, the appropriate analysis of such real-world data is complex and requires close methodological attention. The purpose of this review is to present some of the research conducted within the SCANDAT collaboration. We hope more international collaboration may help improve our understanding of the important remaining questions about donor and recipient health.

No association between frequent apheresis donation and risk of fractures: a retrospective cohort analysis from Sweden

BACKGROUND

Citrate anticoagulation during apheresis induces transient alterations in calcium homeostasis. It is unknown whether the repeated, transient alterations in calcium homeostasis experienced by repeated apheresis donors affects bone turnover to increase fracture risk. Our aim was to investigate the risk of osteoporotic and nonosteoporotic fracture among voluntary, frequent apheresis donors.

STUDY DESIGN AND METHODS

All apheresis donors were identified from the Scandinavian Donations and Transfusions database (SCANDAT2), which includes information on over 1.6 million blood donors from Sweden and Denmark from the years 1968 and 1981, respectively. Only data from Sweden were used for these analyses. Information on fractures was obtained by linking SCANDAT2 to hospital registers. Poisson regression was used to compute incidence rate ratios of fractures in relation to the cumulative number of apheresis donations, both overall and in fixed time windows.

RESULTS

In total, 140,289 apheresis donors (67,970 women and 72,319 men) were identified from the SCANDAT2 database and were followed for up to 23 years. We observed no association between the frequency of apheresis donation and the risk of fracture either in the overall study period or during fixed-length time windows. The incidence rate ratio of fractures in donors who had made 100 or more cumulative apheresis donations was 0.99 (95% confidence interval, 0.92-1.06) compared with donors who had made from 9 to 24 donations. The results were similar in analyses stratified by sex and restricted to postmenopausal women.

CONCLUSIONS

The absence of an association between repeated apheresis donation and fracture risk indicates that apheresis collection is safe with regard to bone health.