Pain is what hurts: An exploration of perception and management of pain in peripheral blood stem cell donors.

BACKGROUND: Pain is a side effect of Granulocyte-Colony Stimulating Factor (G-CSF) administration. This prospective study investigates various aspects including pain perception occurring in Peripheral Blood Stem Cell (PBSC) donors. MATERIALS AND METHODS: Related and unrelated PBSC donors were prospectively studied. Donors recorded pain symptoms during the four-day period of G-CSF administration using the McGill Pain Questionnaire, a Visual Analog Scale and a pain diary. RESULTS: There were 208 donors included, 102 (49%) related and 106 (51%) unrelated donors. Ninety-two percent of all reported the occurrence of pain. Moderate or severe pain was reported by 52%. No differences were found between related and unrelated donors. Pain occurred more often in females (p = 0.035). Relatively young donors (age 16-30 years) more frequently showed to have pain in comparison to older donors (>50 years) (p = 0.006). Musculoskeletal pain was most frequently distributed in the gluteal and lower back region (65-71%). Irrespective of the pain location, pain was most often described as nagging, annoying, however tolerable. Donors experiencing pain most on days of G-CSF administration, most frequently occurring during relaxation or at night. Sleep-mode was often affected. The use of paracetamol (acetaminophen) was sufficient for all but one donor. CONCLUSION: This is the first study to describe different aspects of pain associated with G-CSF administration in donors. Although the observed pain was tolerable, it should never be neglected. Knowledge derived from this study is of use for staff members involved in donor information and care management.

Donors with repeated blood product discards for filtration problems, clots or hemolysis: Causes and follow-up.

INTRODUCTION: Sanquin donor medicine department is informed when donations or their components are rejected. This can occur isolated or frequently. It is undesirable because the donations cannot be used and there may be an underlying medical cause. Based on regional approaches, a uniform procedure was developed. METHODS: Information about whole blood, plasma- plateletpheresis donations from which one or more components were rejected for filtration time (>2 h), hemolysis or clots were extracted from blood bank information system. After rejection of two successive components or donations or total ≥3 the donor is contacted. Depending on the medical history and investigation by the family doctor, the donor carrier is re-evaluated. We looked for the causes of the discarded products and performed a survey among blood services regarding polices with discarded products. RESULTS: One or more components from 1742 of about 2.2 million successful donations (0.08%) were rejected. The highest percentage of rejection was seen in plateletpheresis (1.5%), all for clots. No underlying medical causes were found. 24 whole blood donors were found to have sickle cell trait (SCT) and were permanently deferred. The policies for follow-up after discarded products or acceptance of SCT donors vary between the 16 blood banks. Six organizations do not follow-up donors and seven accept SCT for blood or plasma donation. CONCLUSION: Informing donors with repeated discarded products avoids the non-use of donations. Causes of repeated discarded products can be found by follow-up of donors. The results of the survey indicate a large discrepancy in policies applied worldwide.

Efficacy and safety of platelet additive solution-E stored platelet concentrates.

INTRODUCTION: In 2018, platelet (PLT) additive solution-E (PAS-E) was introduced. The implementation of PAS-E was expected to diminish the number of allergic reactions in recipients following a PLT transfusion. Here, we evaluated the efficacy and safety of transfusions with PLTs stored in PAS-E. STUDY DESIGN AND METHODS: After implementation of PAS-E, data were collected from 2 cohorts of patients with hematological disorders as well as oncology patients, receiving PLTs in PAS-E. A similar patient group in a recent RCT, receiving PLTs in plasma, was used as a historical control group for both cohorts. Endpoints were corrected count increments (CCIs), bleeding scores (only reported in cohort 1), and the incidence of adverse reactions. RESULTS: In cohort 1, the mean 1-h CCI was 14.3 ± 6.9, and the 24-h CCI was 8.7 ± 5.6. In cohort 2, the 1-h CCI was 11.6 ± 7.8 and the 24-h CCI was 7.0 ± 6.1. In the control group, the 1-h CCI was 15.4 ± 5.5 and 24-h CCI 8.7 ± 4.8. Bleeding complications of WHO grade ≥2 occurred in 40% of patients in cohort 1 compared to 44% in plasma PCs. The incidence of adverse reactions was 1.2% in the two PAS-E cohorts, compared to 3.0% in plasma PCs. National hemovigilance data showed a significant reduction in allergic reactions with PAS-E PC transfusions as compared to plasma PCs with an odds ratio of 0.46 (CI 95% 0.37-0.58). CONCLUSION: The CCIs of PLTs in PAS-E were decreased compared to plasma PCs, but clinically acceptable. Allergic transfusion reactions were decreased in PAS-E PCs compared to plasma PCs.

Standardized reporting of pulmonary transfusion complications: Development of a model reporting form and flowchart.

BACKGROUND: Pulmonary complications of blood transfusion, including transfusion-related acute lung injury (TRALI), transfusion-associated circulatory overload (TACO), and transfusion-associated dyspnea, are generally underdiagnosed and under-reported. The international TRALI and TACO definitions have recently been updated. Currently, no standardized pulmonary transfusion reaction reporting form exists and most of the hemovigilance forms have not yet incorporated the updated definitions. We developed a harmonized reporting form, aimed at improved data collection on pulmonary transfusion reactions for hemovigilance and research purposes by developing a standardized model reporting form and flowchart. MATERIALS AND METHODS: Using a modified Delphi method among an international, multidisciplinary panel of 24 hemovigilance experts, detailed recommendations were developed for a standardized model reporting form for pulmonary complications of blood transfusion. Two Delphi rounds, including scoring systems, took place and several subsequent meetings were held to discuss issues and obtain consensus. Additionally, a flowchart was developed incorporating recently published redefinitions of pulmonary transfusion reactions. RESULTS: In total, 17 participants completed the first questionnaire (70.8% response rate) and 14 participants completed the second questionnaire (58.3% response rate). According to the results from the questionnaires, the standardized model reporting form was divided into various subcategories: general information, patient history and transfusion characteristics, reaction details, investigations, treatment and supportive care, narrative, and transfused product. CONCLUSION: In this article, we present the recommendations from a global group of experts in the hemovigilance field. The standardized model reporting form and flowchart provide an initiative that may improve data collected to address pulmonary transfusion reactions.

Reported transfusion-related acute lung injury associated with solvent/detergent plasma - A case series.

BACKGROUND: Antibody-mediated transfusion-related acute lung injury (TRALI) is caused by donor HLA or HNA antibodies in plasma-containing products. In the Netherlands 55,000 units of solvent/detergent plasma (SDP), a pooled plasma product, are transfused yearly. It's produced by combining plasma from hundreds of donors, diluting harmful antibodies. Due to a lack of reported cases following implementation, some have labeled SDP as "TRALI safe". STUDY DESIGN AND METHODS: Pulmonary transfusion reactions involving SDP reported to the Dutch national hemovigilance network in 2016-2019 were reviewed. Reporting hospitals were contacted for additional information, cases with TRALI and imputability definite, probable, or possible were included and informed consent was sought. RESULTS: A total of three TRALI and nine TACO cases were reported involving SDP. The imputability of one TRALI case was revised from possible to unlikely and excluded; in one case no informed consent was obtained. We present a case description of TRALI following SDP transfusion in a 69-year-old male, 3 days following endovascular aortic aneurysm repair. The patient received one unit of SDP to correct a heparin-induced coagulopathy, prior to removal of a spinal catheter post-operatively. Within five hours he developed hypoxemic respiratory failure requiring intubation, hypotension, bilateral chest infiltrates, and leucopenia. The patient made a full recovery. CONCLUSION: This case of TRALI, following transfusion of a single unit of SDP to a patient without ARDS risk factors, demonstrates that TRALI can occur with this product. Clinicians should remain vigilant and continue to report suspected cases, to help further understanding of SDP-associated TRALI.

Guideline development for prevention of transfusion-associated graft-versus-host disease: reduction of indications for irradiated blood components after prestorage leukodepletion of blood components.

Transfusion-associated graft-versus-host disease (TA-GVHD) is a rare, commonly fatal complication of transfusion preventable by irradiation of blood units. The revision of the Dutch transfusion guideline addressed the question whether irradiation is still necessary if blood components are prestorage leukodepleted. We searched for published cases of TA-GVHD following transfusion of prestorage leukodepleted blood and through contacting haemovigilance systems. Six presumed cases were found, dating from 1998 to 2013. Four out of six patients had received one or more non-irradiated units despite recognised indications for irradiated blood components. In the countries providing information, over 50 million prestorage leukodepleted, non-irradiated, non-pathogen-reduced cellular components were transfused in a 10-year period. Potential benefits of lifting indications for irradiation were considered. These include reduced irradiation costs (€ 1.5 million annually in the Netherlands) and less donor exposure for neonates. Findings were presented in an invitational expert meeting. Recommendations linked to human leukocyte antigen similarity between donor and recipient or intra-uterine transfusion were left unchanged. Indications linked to long-lasting deep T-cell suppression were defined with durations of 6 or 12 months after end of treatment (e.g. autologous or allogeneic stem cell transplantation). Need for continued alertness to TA-GVHD and haemovigilance reporting of erroneous non-irradiated transfusions was emphasised.

Complications of blood donation reported to haemovigilance systems: analysis of eleven years of international surveillance.

BACKGROUND AND OBJECTIVES: The International Haemovigilance Network collects aggregate data on complications of blood donation from member haemovigilance systems (HVS). We analysed the data collected in 2006-2016 in order to learn from it and consider future improvements. MATERIALS AND METHODS: National HVS entered annual data on donation complications and on annual whole blood and apheresis donations in the 'ISTARE' (International Surveillance of Transfusion Adverse Reactions and Events) online database. We calculated national and aggregate donation complication rates. RESULTS: Twenty-four HVS provided data for 138 country years (CY; median 7 CY, IQR 2-8), covering 155 M donations. The overall complication rate was 6·3/1000 donations and the median country rate 3·2/1000 (IQR 1·1-10·1). Overall and severe complication rates varied considerably between HVS. Vasovagal reactions (VVR) were most commonly reported: 4·6/1000 donations, median country rate 3·1/1000 donations (IQR 0·6-7·7). Rare complications included generalized allergic reaction (0·10/100 000) and major blood vessel injury (category available since 2015; 0·12/100 000). Eighteen HVS reported complications of whole blood donation (WBD) and apheresis separately (89 CY, 101·6 M WBD and 26·3 M apheresis donations). The median country VVR rate was 3·4/1000 WBD (IQR 1·0-9·1) and 1·5/1000 apheresis donations (1·0-4·2). Rates of venepuncture-related complications tended to be higher for apheresis: the median country rate of reported haematomas was 0·39/1000 WBD (IQR 0·31-1·2) vs. 4·2/1000 apheresis donations (0·69-5·6). CONCLUSION: International reporting allows HVS to study rates of blood donation complications and capture information about very rare events. The present variability of reporting and severity assessment hampers comparisons between HVS and requires further work.

Transition from fresh frozen plasma to solvent/detergent plasma in the Netherlands: comparing clinical use and transfusion reaction risks.

Plasma transfusion is indicated for replenishment of coagulative proteins to stop or prevent bleeding. In 2014, the Netherlands switched from using ~300mL fresh frozen plasma (FFP) units to using 200mL Omniplasma, a solvent/detergent treated pooled plasma (SD plasma), units. We evaluated the effect of the introduction of SD plasma on clinical plasma use, associated bleeding, and transfusion reaction incidences. Using diagnostic data from six Dutch hospitals, national blood bank data, and national hemovigilance data for 2011 to 2017, we compared the plasma/red blood cell (RBC) units ratio (f) and the mean number of plasma and RBC units transfused for FFP (~300mL) and SD plasma (200mL) for various patient groups, and calculated odds ratios comparing their associated transfusion reaction risks. Analyzing 13,910 transfusion episodes, the difference (Δf = fSD - fFFP) in mean plasma/RBC ratio (f) was negligible (Δfentire_cohort = 0.01 [95% confidence interval (CI): -0.02 - 0.05]; P=0.48). SD plasma was associated with fewer RBC units transfused per episode in gynecological (difference of mean number of units -1.66 [95% CI: -2.72, -0.61]) and aneurysm (-0.97 [-1.59, -0.35]) patients. SD plasma was further associated with fewer anaphylactic reactions than FFP (odds ratio 0.37 [0.18, 0.77; P<0.01]) while the differences for most transfusion reactions were not statistically significant. SD plasma units, despite being one third smaller in volume than FFP units, are not associated with a higher plasma/RBC ratio. SD plasma is associated with fewer anaphylactic reactions than FFP plasma/RBC units ratio.

Effect of storage of platelet concentrates in PAS-B, PAS-C, or plasma on transfusion reactions.

BACKGROUND: Reports on the clinical consequences of longer storage time of platelet concentrates are contradictory. The objective of this study was to assess whether longer storage times are associated with a higher risk of transfusion reactions. STUDY DESIGN AND METHODS: We gathered storage times of pooled platelet concentrates related to transfusion reactions reported to the national hemovigilance office from 2004 to 2015. These were combined with storage times of platelet concentrates in the reference population to compare incidences of transfusion-associated circulatory overload, transfusion-related acute lung injury, allergic reactions, febrile nonhemolytic reactions, and "other" reactions between storage time categories. RESULTS: A total of 567,053 platelet concentrates and 1870 transfusion reactions were analyzed. Among platelet additive solution (PAS)-B platelet recipients, the odds ratio of a storage time of 4 to 5 days compared to 1 to 3 days was 1.60 (95% confidence interval [CI], 1.17-2.18) for allergic, and 1.47 (1.09-1.98) for febrile reactions. For PAS-C platelet recipients, the odds ratio for allergic reactions was 3.78 (95% CI, 1.31-10.9) for 4 to 5 days, and 4.57 (95% CI, 1.57-13.4) for 6- to 7-day-old platelets when compared to 1- to 3-day-old units. In all other studied reaction types, no statistically significant association was observed in platelets in plasma, PAS-B, and PAS-C. CONCLUSIONS: In plasma platelets, longer storage time was not associated with a higher incidence of transfusion reactions. In PAS platelets, longer storage time was associated with higher transfusion reaction incidences, in particular for allergic reactions with both PAS fluids and febrile reactions with PAS-B. This indicates that the effect of storage time is different for different reaction types and depends on the storage fluid.

Revised international surveillance case definition of transfusion-associated circulatory overload: a classification agreement validation study.

BACKGROUND: Transfusion-associated circulatory overload (TACO) is a major cause of transfusion-related morbidity and mortality in countries with well developed transfusion services. The International Society of Blood Transfusion, the International Haemovigilance Network, and AABB (formerly American Association of Blood Banks), have developed and validated a revised definition of TACO. METHODS: International Haemovigilance Network-member haemovigilance systems (Australia, Austria, Denmark, Finland, Greece, India, Ireland, Italy, Japan, Malta, Netherlands, New Zealand, Norway, Slovenia, United Kingdom and United States) provided cases of respiratory complications categorised by their systems, including clinical parameters listed in the 2017 draft definition (part 1). Individual transfusion professionals were then invited to assess 24 case descriptions according to the draft definition (part 2). Positive and negative agreement and inter-rater agreement (κ) were calculated. Based on validation results, cases were reanalysed and slight adjustments made to yield the final 2018 TACO definition. FINDINGS: In part 1, 16 (44%) of 36 haemovigilance systems provided 178 cases, including 126 TACO cases. By use of the 2018 definition, 96 (76%) of 126 cases of TACO were in positive agreement. 19 (37%) of 52 cases were recognised as non-TACO respiratory complications. In part 2 (47 experts from 20 countries), moderate all-case agreement (κ=0·43) and TACO-specific agreement (κ=0·54) were observed. Excluding cases missing some clinical information (eg, N terminal pro-brain natriuretic peptide, distinctive chest x-ray findings, and relationship with existing respiratory co-morbidities like pneumonia and chronic obstructive pulmonary disease) improved all-case agreement to κ=0·50 (moderate) and κ=0·65 (good) for TACO cases. INTERPRETATION: The two-part validation exercise showed that the revised 2018 TACO surveillance case definition captures 76% of cases endorsed as TACO by participating haemovigilance systems. This definition can become the basis for internationally consistent surveillance reporting and contribute towards increased awareness and mitigation of TACO. Further research will require reporting more complete clinical information to haemovigilance systems and should focus on improved distinction between TACO and other transfusion respiratory complications. FUNDING: International Society of Blood Transfusion, International Haemovigilance Network, and AABB.

Transfusion reactions after transfusion of platelets stored in PAS-B, PAS-C, or plasma: a nationwide comparison.

BACKGROUND: Platelets (PLTs) stored in PLT additive solution (PAS) are associated with fewer allergic reactions than plasma-stored PLTs. However, earlier studies could not provide conclusive evidence on febrile reactions and did not analyze other transfusion reactions separately due to limited sample size. We therefore compared incidences of all transfusion reactions of PAS-B-PLTs, PAS-C-PLTs, and plasma-PLTs. STUDY DESIGN AND METHODS: In this observational study, all transfusion reactions reported to the national hemovigilance office of the Netherlands from 2006 to 2015 were included. RESULTS: During the study period, a total of 2407 transfusion reactions after PLT transfusions were reported. In that period 553,267 pooled buffy coat-derived PLT units were issued, of which 83,884 were stored in PAS-B, 45,728 in PAS-C, and 423,655 in plasma. Regarding transfusion-related circulatory overload, transfusion-related acute lung injury, and "other reactions" no significant differences were observed between the PLT products. When PAS-B-PLT transfusions were compared to plasma-PLT transfusions, the overall relative risk (RR; 95% confidence interval [CI]) of transfusion reactions was 0.99 (0.88-1.11); for allergic and febrile nonhemolytic transfusion reactions (FNHTRs) it was 0.66 (0.55-0.80) and 1.54 (1.27-1.86), respectively. When PAS-C-PLTs were compared to plasma-PLTs, the RR (95% CI) was 0.56 (0.46-0.68) for all transfusion reactions, 0.38 (0.28-0.52) for allergic reactions, and 0.82 (0.59-1.13) for FNHTRs. When PAS-C-PLTs were compared to PAS-B-PLTs, for all reactions the RR (95% CI) was 0.56 (0.45-0.70) for allergic reactions 0.58 (0.40-0.82), and for FNHTRs 0.53 (0.37-0.75). CONCLUSIONS: PAS-C-PLTs are associated with fewer transfusion reactions compared to plasma-PLTs and compared to PAS-B-PLTs.

Comparing transfusion reaction risks for various plasma products - an analysis of 7 years of ISTARE haemovigilance data.

Plasma transfusions may result in transfusion reactions. We used the International Surveillance of Transfusion-Associated Reactions and Events (ISTARE) database, containing yearly reported national annual aggregate data on transfusion reactions from participating countries, to investigate risks of plasma transfusion reactions and compare transfusion reaction risks for different plasma types. We calculated risks for plasma transfusion reactions and compared transfusion reaction risks between plasma types using random effects regression on repeated measures. The ISTARE database contains data from 23 countries, reporting units issued and/or transfused and transfusion reactions observed for some portion of 7 years (2006-2012). Interquartile ranges (IQRs) of plasma transfusion reaction risks were: allergic reactions (5·6-72·2 reactions/105 units transfused); febrile non-haemolytic transfusion reactions (0-9·1); transfusion-associated circulatory overload (0-1·9); transfusion related acute lung injury (TRALI) (0-1·2); and hypotensive reactions (0-0·6). Apheresis plasma was associated with more allergic reactions [odds ratio (OR) = 1·29 (95% confidence interval: 1·19-1·40)] and hypotensive reactions [OR = 2·17 (1·38-3·41)] than whole blood-derived plasma. Pathogen-inactivated plasma was associated with fewer transfusion reactions than untreated plasma.

Comparing transfusion reaction rates for various plasma types: a systematic review and meta-analysis/regression.

BACKGROUND: We estimated rates for common plasma-associated transfusion reactions and compared reported rates for various plasma types. STUDY DESIGN AND METHODS: We performed a systematic review and meta-analysis of peer-reviewed articles that reported plasma transfusion reaction rates. Random-effects pooled rates were calculated and compared between plasma types. Meta-regression was used to compare various plasma types with regard to their reported plasma transfusion reaction rates. RESULTS: Forty-eight studies reported transfusion reaction rates for fresh-frozen plasma (FFP; mixed-sex and male-only), amotosalen INTERCEPT FFP, methylene blue-treated FFP, and solvent/detergent-treated pooled plasma. Random-effects pooled average rates for FFP were: allergic reactions, 92/105 units transfused (95% confidence interval [CI], 46-184/105 units transfused); febrile nonhemolytic transfusion reactions (FNHTRs), 12/105 units transfused (95% CI, 7-22/105 units transfused); transfusion-associated circulatory overload (TACO), 6/105 units transfused (95% CI, 1-30/105 units transfused); transfusion-related acute lung injury (TRALI), 1.8/105 units transfused (95% CI, 1.2-2.7/105 units transfused); and anaphylactic reactions, 0.8/105 units transfused (95% CI, 0-45.7/105 units transfused). Risk differences between plasma types were not significant for allergic reactions, TACO, or anaphylactic reactions. Methylene blue-treated FFP led to fewer FNHTRs than FFP (risk difference = -15.3 FNHTRs/105 units transfused; 95% CI, -24.7 to -7.1 reactions/105 units transfused); and male-only FFP led to fewer cases of TRALI than mixed-sex FFP (risk difference = -0.74 TRALI/105 units transfused; 95% CI, -2.42 to -0.42 injuries/105 units transfused). CONCLUSION: Meta-regression demonstrates that the rate of FNHTRs is lower for methylene blue-treated compared with FFP, and the rate of TRALI is lower for male-only than for mixed-sex FFP; whereas no significant differences are observed between plasma types for allergic reactions, TACO, or anaphylactic reactions. Reported transfusion reaction rates suffer from high heterogeneity.

Storage medium of platelet transfusions and the risk of transfusion-transmitted bacterial infections.

BACKGROUND: Transfusion-transmitted bacterial infections (TTBIs) are among the most concerning risks of transfusion of platelet (PLT) concentrates. Storage medium influences bacterial growth dynamics and thereby the sensitivity of screening tests for bacterial contamination. STUDY DESIGN AND METHODS: The aim of this study was to quantify the association of storage media with the incidence of TTBIs after transfusion of PLT concentrates. In the Netherlands, the choice of storage medium is determined solely by geographic location of the hospital. We compared types of storage medium of all reported cases of TTBIs after transfusion of a PLT concentrate with types of storage medium of all produced PLT concentrates in the Netherlands from 2003 to 2014. RESULTS: Fourteen cases of TTBIs were reported, of which 57.1% received a PLT concentrate stored in PLT additive solution (PAS) and 42.9% a PLT concentrate stored in plasma. Of all produced PLT concentrates 22.3% were stored in PAS and 77.7% in plasma. The relative risk of TTBI after transfusion of a PAS-stored PLT concentrate was 4.63 (95% confidence interval [CI], 1.4-16.2) compared to transfusion of a plasma-stored PLT concentrate. The incidence of TTBIs was 22.2 per million (95% CI, 12.1-37.2 per million) transfused buffy coat PLT concentrates. CONCLUSION: Transfusion of PAS-stored PLT concentrates is associated with a fourfold increased incidence of TTBIs, compared to plasma-stored PLT concentrates.

Wrong blood in tube - potential for serious outcomes: can it be prevented?

'Wrong blood in tube' (WBIT) errors, where the blood in the tube is not that of the patient identified on the label, may lead to catastrophic outcomes, such as death from ABO-incompatible red cell transfusion. Transfusion is a multistep, multidisciplinary process in which the human error rate has remained unchanged despite multiple interventions (education, training, competency testing and guidelines). The most effective interventions are probably the introduction of end-to-end electronic systems and a group-check sample for patients about to receive their first transfusion, but neither of these eradicates all errors. Further longer term studies are required with assessment before and after introduction of the intervention. Although most focus has been on WBIT in relation to blood transfusion, all pathology samples should be identified and linked to the correct patient with the same degree of care. Human factors education and training could help to increase awareness of human vulnerability to error, particularly in the medical setting where there are many risk factors.

Risk factors for complications in donors at first and repeat whole blood donation: a cohort study with assessment of the impact on donor return.

BACKGROUND: First-time donation is among recognised risk factors for vasovagal reactions to blood donation and reactions are known to reduce donor return. We assessed associations between potential risk factors and vasovagal reactions and needle-related complications in first-time whole blood donation in comparison to repeat donation and analysed the impact of complications on donor return. MATERIALS AND METHODS: We performed a cohort study on whole blood donations in The Netherlands from 1/1/2010 to 31/12/2010 using data extracted from the blood service information system. Donation data up to 31/12/2011 were used to ascertain donor return. RESULTS: In 2010 28,786 donors made first whole blood donations and there were 522,958 repeat donations. Vasovagal reactions occurred in 3.9% of first donations by males and 3.5% of first donations by females compared to in 0.2% and 0.6%, respectively, of repeat donations. Associations of vasovagal reactions with other factors including age, body weight, systolic and diastolic blood pressure were similar in first-time and repeat donors. Needle-related complications occurred in 0.2% of male and 0.5% of female first-time donations and in 0.1% and 0.3%, respectively, of repeat donations. Among first-time donors, the return rate within 1 year was 82% following an uncomplicated first donation, but 55% and 61% following vasovagal reactions and needle-related complications, respectively; the corresponding percentages among repeat donors were 86%, 58% and 82%. DISCUSSION: Among first-time donors, females suffered less than males from vasovagal reactions. Other risk factors had similar associations among first-time and repeat donors. Vasovagal reactions and needle-related complications in both first-time and repeat donors are followed by reduced donor return.