Do reactions after whole blood donation predict syncope on return donation?

BACKGROUND: Adverse reactions after whole blood donation reduce the likelihood of a subsequent donation. Still, many donors return to give blood even after experiencing a reaction. Consequently, we evaluated the risk of recurrent syncope among returning donors. STUDY DESIGN AND METHODS: Allogeneic whole blood donors in 2009 who had vasovagal‐type reactions including syncope were evaluated for return donation within 12 months and subsequent reactions, based on donation status (novice [first‐time] or active [repeat]) or age at index donation. RESULTS: Syncope after a first whole blood donation significantly reduced the frequency of return donation (18%), compared to either presyncopal symptoms (27%; p < 0.0001) or no reaction (35%; p < 0.0001). Among novice donors who returned to donate, syncope was more likely among donors who had any reaction (0.8%) or syncope (3.5%) at their first donation, compared to donors who had no reaction (0.3%; p < 0.0001). Syncope at a first donation identified only 2% (19 of 1062) of syncopal reactions among returning donors. For active, repeat donors who experienced syncope in 2009, a history of prior reactions had no effect on the likelihood of return donation or recurrent syncope. CONCLUSION: Donation experience strongly influences the likelihood of return donation and the risk of subsequent reactions, but a prior reaction after whole blood donation does not reliably predict recurrent syncope among returning donors.     

Vasovagal reaction rates and body weight: findings in high- and low-risk populations

BACKGROUND: The effect of weight on vasovagal reaction rates has not been evaluated in high- and low-risk populations or in first-time versus repeat blood donors. In addition, vasovagal reaction rates and weight have not been evaluated based on solicited information. STUDY DESIGN AND METHODS: A total of 1073 Caucasian high school students from randomly selected whole-blood drives in 2001 and 949 randomly selected Caucasian donors from the general donor population in 2001 and 2002 were subdivided into weight groups and evaluated for vasovagal reaction rates. RESULTS: The high school population had a much higher vasovagal reaction rate than the general donor population (8.0 vs. 2.6%). The vasovagal reaction rate was inversely proportional to body weight in first-time blood donors in both populations, but the trend was not as well defined in repeat blood donors. Solicitation of information from the general donor population increased the vasovagal reaction detection rate by 2.5 times (from 2.6% to 6.5%), and it is suggested that the vasovagal reaction rate might be as high as 27 percent in first-time general donors who weighed between 110 and 139 pounds. CONCLUSION: Body weight is a very important determinant of vasovagal reaction rates in first-time donors, but previous successful blood donation appears to mitigate the effect of body weight on vasovagal reaction rates. Solicitation of information from blood donors increases the number of vasovagal reactions detected and enhances the data.     

Predonation water ingestion attenuates negative reactions to blood donation

BACKGROUND: Novice blood donors are at increased risk for unpleasant blood donation-related symptoms (e.g., dizziness, weakness, and lightheadedness), and the experience of such symptoms can contribute to a decreased likelihood of repeat donation. Recent laboratory studies suggest that water ingestion produces hemodynamic effects that may be sufficient to reduce risk of syncope and related reactions during blood donation. STUDY DESIGN AND METHODS: Male and female volunteers were randomly assigned to ingest either 500 or 0 mL of water 30 minutes before donating blood for the first time. In addition, bioimpedance analysis was used to assess predonation chronic hydration levels in all donors. Immediately after donation, participants completed the Blood Donation Reactions Inventory to assess subjective experience of negative physiologic reactions. RESULTS: Analysis of Blood Donation Reactions Inventory scores revealed that predonation water ingestion was associated with a 47-percent reduction of total donation-related symptoms (F [1,79]= 11.81, p = 0.001). Chronic hydration status was not related to reported reactions. CONCLUSION: Novice blood donors responded positively to predonation water consumption, and they were able to consume 500 mL in less than 5 minutes. Results of the present study suggests that predonation water ingestion may be a simple and cost-effective strategy to enhance the donation experience and possibly increase donor retention.     

Improved safety for young whole blood donors with new selection criteria for total estimated blood volume

BACKGROUND: Young age, first‐time donation status, and estimated blood volume (EBV) are leading determinants of syncopal complications after whole blood donation. We evaluated a multifaceted safety initiative and more restrictive selection criteria for whole blood donation by individuals younger than 19 years. STUDY DESIGN AND METHODS: Measures introduced over 2 years addressed donor education, drive environment and supervision, and new eligibility criteria for EBV of 3.5 L or more based on height, weight, and sex for individuals younger than 19 years. Presyncopal and syncopal reactions after whole blood donation during the school year in the baseline, transitional (2008), and full implementation (2009) periods were evaluated. RESULTS: Young donors (16‐ to 18‐years‐olds) gave 754,402 and 710,922 whole blood donations in the 2008 and 2009 school years accounting for 16% of the total collections in both 9‐month study periods. The new selection criteria were associated with a significant reduction in the reaction rates among 16‐ to 18‐year‐olds. Sixteen‐year‐old donors had the greatest decrease in 2009 compared to baseline for presyncopal reactions (10.5% vs. 7.3%; odds ratio [OR], 0.67; 95% confidence interval [CI], 0.65‐0.69) and syncope (43.1 vs. 37.1 per 10,000 donations; OR, 0.86; 95% CI, 0.77‐0.96). Donor subgroup analysis by sex, age, and donation status demonstrated that age‐related differences in reaction rates were eliminated in 2009. CONCLUSION: The safety initiative with new selection criteria for EBV led to decreased complications among donors 16 to 18 years old, such that the risk for 16‐year‐olds was no longer different from that observed for 19‐year‐olds in the analysis stratified by age, sex, and donation status.     

Predonation hydration and applied muscle tension combine to reduce presyncopal reactions to blood donation

BACKGROUND: A randomized controlled trial was conducted to test the effects of hydration and applied muscle tensing on presyncopal reactions to blood donation. Both interventions are designed to prevent the decreases in blood pressure that can contribute to such reactions, but due to the distinct physiologic mechanisms underlying their pressor responses it was hypothesized that a combined intervention would yield the greatest benefit. STUDY DESIGN AND METHODS: Before blood donation, first‐ and second‐time blood donors (mean age, 20.2 years; SD, 4.9) were randomly assigned to 1) standard donation, 2) placebo (leg exercise before venipuncture), 3) predonation water, or 4) predonation water and leg exercise during donation. RESULTS: Main effects of group were observed for phlebotomist classification of vasovagal reactions (χ²(3) = 8.38, p < 0.05) and donor reports of presyncopal reactions (χ²(3) = 13.16, p < 0.01). Follow‐up analyses of phlebotomist classifications revealed fewer reactions in the predonation water and predonation water and leg exercise groups relative to placebo but not standard donation. Follow‐up analyses of self‐reported reactions revealed that women, but not men, had lower scores in both the predonation water and the predonation water and leg exercise groups relative to both placebo and standard donation. CONCLUSIONS: Predonation hydration and a combination of hydration and leg exercise may help attenuate presyncopal reactions in relatively novice donors, although future studies with larger samples are required to confirm this effect.     

Vasovagal reactions in blood donors during or immediately after blood donation

The aim of the study was to estimate the type, incidence and causes of donor adverse reactions during and after blood donation in a Greek Blood Bank, where medical staff is responsible for donor selection. 12 173 blood donors were studied for adverse reactions. One-hundred and seven (0.87%) donors had a vasovagal reaction during or after blood donation. Donors who gave blood occasionally had a significant greater incidence of reactions compared with volunteer donors (1.15 versus 0.53%) (P < 0.001). There was no significant difference between men and women (0.85 versus 0.95%). First-time donors (1.7 versus 0.68%) and those under 30 years (1.15 versus 0.71%] had a significant greater possibility to have a reaction (P < 0.001). Twenty-two of 107 (20.5%) donors had a syncopal reaction. There was not a causative correlation of haematocrit, haemoglobin, systolic and diastolic blood pressure, pulse rate and weight in women (except weight in men) in developing a reaction. The stressing experience of phlebotomy was the reason for the higher frequency of a reaction. The incidence of reactions in our donors is lower than in other studies, and the possible reason for this is that only physicians are responsible for the selection of donors and trained personnel are careful of them during the donation process.     

Donation reactions among autologous donors

Studies of risk factors associated with reactions among autologous blood donors have been limited. Therefore, 2091 autologous and 4737 homologous donations were examined. Donors at greatest risk for reaction were autologous donors who had reactions at first donation; among 45 who made repeat donations for the same surgery, 17 (38%) had repeat reactions. The group least likely to experience reactions were the autologous donors greater than or equal to 66 years old; they experienced a 1.9 greater than or equal to percent (6/310) incidence of reactions. More reactions were seen in both autologous and homologous donors in the categories of first-time donor, female gender, decreasing age, and lower weight. Multiple logistic regression analysis showed that all of these variables were independent predictors of donor reaction, with first-time donation (odds ratio, 2.4) and female gender (odds ratio, 1.9) being the strongest predictors of reaction. Donor room personnel should be alerted that autologous donors who react at first donation are very likely to react at subsequent donations. Contrary to common concern, elderly autologous donors are least likely to have reactions.     

Assessment of donor fear enhances prediction of presyncopal symptoms among volunteer blood donors

BACKGROUND: Fear is an important contributor to the risk of presyncopal reactions to blood donation. However, concern that asking donors about their fears may increase the risk of reactions is a potential impediment to incorporating fear assessment into donor screening. STUDY DESIGN AND METHODS: Before donation, participants responded to a series of questions that either did (n = 488) or did not (n = 494) include questions related to fear of seeing blood drawn. Immediately after donation all participants provided ratings of presyncopal reactions. RESULTS: Among those asked predonation fear questions, fear was most strongly related to presyncopal symptoms when compared against other donor characteristics (e.g., age, number of prior donations, body mass index, estimated blood volume, blood pressure, and pulse). However, Mann‐Whitney U tests revealed that being asked about fear before donation was not associated with higher reports of presyncopal reactions for the sample as a whole, nor among novice donors. Further, regression analyses indicated that fear remained a significant predictor of presyncopal reactions in final models that included age and number of prior donations as significant predictors. CONCLUSION: Predonation assessment of fear of blood draws may help to identify donors who are most likely to benefit from brief interventions designed to enhance donor coping, reduce risk of presyncopal reactions, and increase donor retention.     

Prevalence of selected viral infections among temporarily deferred donors who returned to donate blood: American Red Cross blood donor study

BACKGROUND: Health history questions are introduced into the predonation interview to identify blood donors believed to pose a higher risk of infectious diseases to recipients. This study assesses the current impact of some of those questions. STUDY DESIGN AND METHODS: Donor deferral and donation data were extracted from a research database of the American Red Cross. The prevalence of hepatitis B surface antigen or antibodies to human immunodeficiency virus, hepatitis C virus, or human T-lymphotropic virus was obtained for different groups of donors who were temporarily deferred in 2000 through 2001 and later returned to donate blood in 2000 through 2003. The results were compared with either first-time or repeat donors in 2000 through 2003, while controlling for differences in sex, age, and year of donation. RESULTS: Of donors temporarily deferred in 2000 through 2001 who had had no donation or deferral during the previous 2 years, only 22.08 percent subsequently returned to donate blood in 2000 through 2003. Donations from returning donors who had been deferred for potential infectious disease risk did not show a higher prevalence for any of the viral markers when those with no donation or deferral during the previous two years were compared with first-time donations, and those with prior donation were compared with repeat donations. CONCLUSION: Blood donors temporarily deferred in 2000 through 2001 for potential risk of viral infection who later returned to donate blood did not appear to pose a higher risk compared to first-time or repeat donors. The effectiveness of some of the currently used deferral questions in reducing viral risks warrants further study.     

How afraid are you of having blood drawn from your arm? A simple fear question predicts vasovagal reactions without causing them among high school donors

BACKGROUND: We previously demonstrated in a group of mostly experienced blood donors that fear of blood draws was a significant predictor of vasovagal reactions. Importantly, being asked about one's fear immediately before donation did not increase reaction rates. This study further evaluates the relationship between fear and reactions among high school blood donors, who are known to be at a relatively greater risk for vasovagal reactions. STUDY DESIGN AND METHODS: Immediately after completing the blood donor health screening, 17‐ and 18‐year‐old high school students were asked about their fear of having blood drawn. Based on a random selection, the fear question was administered in approximately half of the schools, resulting in a final sample of 1715 donors who did and 1692 donors who did not answer the fear question. RESULTS: Fear was a significant predictor of donor reactions and remained a significant independent predictor (along with estimated blood volume and donor sex) in a logistic regression analysis. There was no difference in the proportion of reactions observed between those who did and did not answer the predonation fear question. CONCLUSION: Consistent with previous evidence in older and more experienced blood donors, these findings indicate that assessing fear of blood draws may help to identify those who are most likely to experience vasovagal reactions among young donors without increasing the frequency of such reactions.     

Improving safety for young blood donors

Young blood donors between the ages of 16 and 18 years contribute substantially to the blood supply in the United States, accounting for about 14% of the allogeneic whole blood collected by the American Red Cross in 2010. However, studies have consistently demonstrated that the donors' age, total blood volume, and first-time donation status independently contribute to the risk of syncopal reactions after whole blood donation. Efforts to improve the donation experience are crucial not only to ensure the health and well-being of blood donors but also to sustain an adequate blood supply. Even minor reactions or temporary deferrals discourage individuals from donating blood again. Shifting population demographics and advances in medical care in the United States and other countries predict that the need for blood will increase, whereas blood donation by the older generations declines each year. Broad deferral strategies and precautionary measures have further winnowed the eligible donor pool, but their contribution to transfusion safety remains controversial. Consequently, blood centers that depend on recruiting and retaining adolescent blood donors have made concerted efforts to improve safety, especially on high school blood drives. Population-based operational tactics to improve donation safety focus on donor education, the drive environment, or recruiting individuals who are less likely to have reactions. Physiologic strategies modulate the donors' response to blood loss, decreasing their susceptibility to a donation-related reaction. This review examines the published data supporting the measures recently taken by blood centers to reduce the risk of syncopal reactions among young, whole blood donors.     

Donors who react may not come back: analysis of repeat donation as a function of phlebotomist ratings of vasovagal reactions.

Previous studies using small or restricted samples suggest that vasovagal reactions to blood donation are associated with a decreased likelihood of repeat donation. In the present study, we examined data for all allogeneic whole blood donors (n=89,587) in the American Red Cross Blood Services, Central Ohio Region during an entire year. Results of a one-year follow-up revealed that moderate and severe vasovagal reactions reduced the likelihood of repeat donation by 50% or more. Light vasovagal reactions, which represented 97% of all reactions recorded, significantly reduced return rates by 20% for first-time donors and 33% for experienced donors.     

Vasovagal reactions in whole blood donors at three REDS-II blood centers in Brazil

BACKGROUND: In Brazil little is known about adverse reactions during donation and the donor characteristics that may be associated with such events. Donors are offered snacks and fluids before donating and are required to consume a light meal after donation. For these reasons the frequency of reactions may be different than those observed in other countries. STUDY DESIGN AND METHODS: A cross‐sectional study was conducted of eligible whole blood donors at three large blood centers located in Brazil between July 2007 and December 2009. Vasovagal reactions (VVRs) along with donor demographic and biometric data were collected. Reactions were defined as any presyncopal or syncopal event during the donation process. Multivariable logistic regression was performed to identify predictors of VVRs. RESULTS: Of 724,861 donor presentations, 16,129 (2.2%) VVRs were recorded. Rates varied substantially between the three centers: 53, 290, and 381 per 10,000 donations in Recife, São Paulo, and Belo Horizonte, respectively. Although the reaction rates varied, the donor characteristics associated with VVRs were similar (younger age [18‐29 years], replacement donors, first‐time donors, low estimated blood volume [EBV]). In multivariable analysis controlling for differences between the donor populations in each city younger age, first‐time donor status, and lower EBV were the factors most associated with reactions. CONCLUSION: Factors associated with VVRs in other locations are also evident in Brazil. The difference in VVR rates between the three centers might be due to different procedures for identifying and reporting the reactions. Potential interventions to reduce the risk of reactions in Brazil should be considered.     

Vasovagal reactions in high school students: findings relative to race,risk factor synergism,female sex,and non-high school participants

BACKGROUND: High school (HS) students have a high incidence of vasovagal reactions and are a good population for the study of vasovagal reactions. STUDY DESIGN AND METHODS: Data from 1,076 Caucasian students, 226 African-American students, and 157 nonstudents from HS blood drives in 2001 were entered into a database. Race, high-risk-factor synergism, the phenomenon of "survivorship," and female sex were evaluated. In addition, non-HS student participants were described. RESULTS: Vasovagal reactions were 84 percent lower in African-American HS students than in Caucasian HS students (3 of 226 vs. 88 of 1,076; 1.3 vs. 8.2 percent; p = 0.0001; relative risk, 6.2). In Caucasian HS students, first-time donor status increased the vasovagal reaction rate to 9.4 percent (vs. 3.6% in repeat donors, p < 0.004). Low weight ( 81.2 kg, p < 0.001). Together they increased the reaction rate to 16.0 percent (vs. 3.2%, p < 0.0001). Females had more reactions than males (11.3 vs. 4.8%, p < 0.001), but the reaction rates equalized when donors under 150 lb were excluded (5.7 vs. 4.6%, p = 0.66). CONCLUSION: African-American HS students had a significantly lower vasovagal reaction rate than Caucasian HS students. There was synergy among high-risk factors in Caucasian HS students. Female and male vasovagal reaction rates were similar when low-weight donors were excluded.     

Moderate and severe reactions in blood donors

During the period April 1985 to March 1986, 217 blood donors were found to have moderate (syncopal) to severe (convulsive) reactions. This population was compared to 5630 randomly selected donors who did not have reactions. An examination of demographic, physical, and societal/emotional factors was conducted to determine if any were predictive of reactions in donors. The results of the research supported the hypothesis that first-time donors have a higher frequency of reactions (1.7%) than do repeat donors (0.19%). A review of the above predictive factors documented that, with regard to demographic factors, 1) the number of prior donations was inversely proportional to the risk of reaction; 2) the gender of the donor was not predictive; and 3) youth was a predictor of reactions. An analysis of the physical factors revealed that donors who reacted were of lower weight (mean, 153.7 lb) than those who did not (mean, 166.4 lb) and that systolic blood pressure was slightly lower in the group with reactions. Although the difference was significant (3 torr), it was not thought to be significant clinically. In a comparison of a group with systolic blood pressure ranging from 80 to 100 torr and a group with systolic blood pressure ranging from 120 to 140 torr, the first group had a 70-percent higher risk of reaction. Finally, with regard to the last category of societal or emotional factors, the research demonstrates 1) that the ingestion of caffeinated beverages was associated with a reduced risk of reactions; 2) that the food intake of donors who reacred was significantly different from that of those who had no reaction, but this difference was not thought to be clinically significant; and 3) that the duration between registration and the onset of phlebotomy was directly predictive of reaction status. The research indicates that first-time donor status and several specific demographic, physical, and societal or emotional factors are predictors of donor reactions.     

Donor retention as a function of donor reactions to whole-blood and automated double red cell collections

BACKGROUND: Although reactions to whole-blood (WB) donation are known to decrease donor retention, potential effects of reactions to automated double red cell (2RBC) donation upon retention have not been investigated. STUDY DESIGN AND METHODS: The authors investigated effects of donor status (first-time, experienced) and reactions (absent, present) upon retention of all male allogeneic WB and 2RBC donors (n = 45,296) donating within the American Red Cross Central Ohio Region during a 12-month period. Donor age, race, and status (first-time, experienced); phlebotomist's reaction rating; and phlebotomy procedure (WB, 2RBC) were collected for the initial donation by each donor. Dates of any donation attempts in the 12 months starting from the donor's first eligible date after the initial donation were also collected. RESULTS: On average, WB donors were less likely to react and more likely to donate again and returned more quickly to donate than 2RBC donors, even after accounting for differential delays in eligibility. Reactions decreased the likelihood of repeat donation among all first-time donors regardless of initial phlebotomy procedure. Among experienced donors, however, reactions depressed retention of WB donors by 27.6 percent, whereas reactions lowered retention of 2RBC donors by just 3.6 percent. CONCLUSION: Although 2RBC donors were more likely to react, first-time 2RBC donors were no more affected by reactions than first-time WB donors. Experienced WB donors suffered a larger drop in retention as a function of reactions, in fact, than did experienced donors who gave 2RBC donations. Potential reasons for this data pattern require further investigation.     

血管迷走神经性献血反应的相关因素分析

目的探讨血管迷走神经性献血反应的相关影响因素,为制定有效的干预措施提供依据。方法回顾性调查2013年1月至2017年12月宜昌市献血人群,其中发生的490例血管迷走神经性献血反应的献血者资料,分析影响血管迷走神经性献血反应的相关因素。结果初次献血、低年龄(18-24岁)、学生、男性、低体重(<55 Kg)、街头献血是血管迷走神经性献血反应发生的影响因素,且影响程度依次为初次献血(OR值6.141,95%CI 4.908—7.684)、低年龄(OR值3.271,95%CI为2.735—3.912)、学生(OR值2.811,95%CI为2.277—3.470)、低体重(OR值1.345,95%CI为1.121—1.614)、男性(OR值1.254,95%CI为1.038—1.515)、街头献血(OR值1.245,95%CI为1.034—1.498)。结论心理因素是影响血管迷走神经性献血反应发生的主要因素,在献血全过程中应特别注意对初次献血、低年龄(18—24岁)、学生献血者的心理护理,采取针对性的预防措施,保障献血者安全。     

Quantifying losses to the donated blood supply due to donor deferral and miscollection

BACKGROUND: Donors are deferred for multiple reasons. Losses related to disease marker rates are well established. Donor and donation losses for other reasons, however, have not been extensively quantified. STUDY DESIGN AND METHODS: To quantify these losses, three data sets from the Blood Centers of the Pacific were combined, permitting detailed analysis of year 2000 allogeneic whole-blood donations. RESULTS: During 2000, 13.6 percent of 116,165 persons who presented for donation were deferred at presentation. Short-term deferral accounted for 68.5 percent (hematocrit was most common at 60%); long-term deferral accounted for 21 percent (travel to a malarial area and tattoo or other nonintravenous drug use needle exposure were most common at 59 and 29%, respectively); and multiple-year or permanent deferral accounted for 10.5 percent (UK travel [variant Creutzfeldt-Jakob disease] risk and emigration from a malarial area were most common at 38 and 11%, respectively). Disease-marker-reactive donations represented 0.9 percent of donor outcomes. The prevalence of deferral and also miscollection (under- and overweight units) varied by age, sex, and first-time versus repeat donor status. Overall, miscollection led to a loss of 3.8 percent of 100,141 collections, ranging from 1.9 percent in repeat male donors 40 to 54 years of age to 10.7 percent in first-time female donors 16 to 24 years of age. CONCLUSION: Loss of units from both first-time and repeat donors due to temporary deferral and loss of units from miscollection are more common events than losses due to disease marker testing. Some of these losses may be avoidable and could increase the blood supply without having to recruit new donors.     

全血献血者离场血管迷走神经反应相关因素分析

目的 探讨全血献血者发生离场血管迷走神经反应影响因素,为采取预防性策略提供依据.方法 调查2019年度全血采集离场血管迷走神经反应情况,献血者性别、年龄、献血次数、体重、季节等相关因素进行分类整理与分析.结果 全血400mL捐献42 874人次中发生离场血管迷走神经反应非重度67例,重度0例,占比0.16％,单因素、多...     

A study of 178 consecutive vasovagal syncopal reactions from the perspective of safety

BACKGROUND: While vasovagal syncopal reactions have been studied in the past, there are several safety questions that could be further addressed. The purpose of this study was to address these safety questions. STUDY DESIGN AND METHODS: One hundred seventy-eight vasovagal reactions were reported in 1999 from 194,000 blood donations. The reactions were retrospectively reviewed for 38 variables that included donor demographics, symptoms, injury, and final disposition. RESULTS: Sixty-one percent of the syncopal reactions occurred at the refreshment table and 12 percent offsite. Fourteen percent of the donors sustained an injury, usually to the head (10%). Eleven donors (6%) had additional medical care in an emergency room: 4 for injuries, 3 for delayed recovery, and 4 for offsite syncope. None of the donors was admitted to the hospital. One of the injured donors developed postconcussion syndrome and had later sequelae. CONCLUSION: Syncopal reactions most commonly occur at the refreshment table, where preventive safety measures against trauma could be applied. A significant number of syncopal reactions occur offsite, where the environment is less safe. The injuries that occur, particularly to the head, may in rare cases lead to long-term sequelae.