Would you like another pretzel? Water? We make progress in donor reactions

Many controlled studies of interventions to reduce donor vasovagal or similar “loss of consciousness” (syncope) or “pre-faint” (presyncope) reactions in the blood donor have been undertaken, and several interventions have been shown to be effective in smaller-scale clinical trials. The report from Canadian Blood Services (CBS) in this issue extends this knowledge, reporting a real-world experience in a large, national blood donor collection establishment before and after focused interventions. Using a suite of tools, CBS was able to reduce rates of syncope by approximately 25%. This is significant progress on a problem that continues to challenge those of us dedicated to blood collection. With such improvement, why do we need to continue to work on this issue? First, our ethical obligation is to protect the safety of the volunteer blood donor, who is contributing altruistically to a person he or she doesn't even know. Most vasovagal reactions are mild and not important medically, but about 6% may lead to falls, some with traumatic consequences such as broken bones, teeth, and head injuries. Legal and financial liability can certainly ensue. The reaction may have impact beyond the medical harm, though. Significantly, the donor who has a reaction is less likely to return, to become that “repeat donor” that all blood collectors covet. Additionally, a donor who has a visible reaction that requires care can alarm those already donating or those waiting to donate, potentially leading to increased fainting episodes simply due to the power of suggestion (the domino effect). Staff may also be distracted from care of other donors. Collectors generally try to set up drives with some privacy for a donor having a reaction, but this is not always possible. Moreover, the use of social media by individuals who have suffered an adverse reaction during blood donation should not be underestimated. The number of reactions will affect the public perception of the risk of donation. This may affect the ability of blood collectors to find locations for mobile collections, particularly as institutions such as schools are becoming more risk-averse. If the general perception of blood donation is that it is a risky activity, individuals will also be more reluctant to volunteer to donate. For those who do overcome that barrier, there may be increased anxiety (fearfulness), which can in itself increase the risk of reaction. Transfusion has published editorials on vasovagal donor reactions twice before. In 2002, Mark Popovsky wrote an editorial on two papers. The first, a paper by Newman addressing reactions in high school donors, reported that first-time donor status, weight less than 130 pounds, and female gender were risk factors for reactions, and that gender was a factor only in donors less than 150 pounds. In the same issue, Tomita reported that among women, reaction rates were higher for apheresis donation than for whole blood donation. (This is not the case in the US currently, as apheresis donations, with saline volume replacement, have a lower rate of donor reaction than whole blood donation.) These approaches led to further descriptive work in identifying the donors who were most likely to have reactions. Almost a decade later, we had moved from descriptive studies to trials of interventions, based on the presumed physiology of donor reactions and general experience. Young donors were identified as a group at high risk, and both the American Red Cross (ARC) and Blood Systems (BSI, now Vitalant) took steps addressing this group in particular. The most important change was to defer young donors with smaller blood volumes (less than 3500 mL), so the volume of whole blood withdrawn in a standard donation would not exceed 15% of the total estimated blood volume. In a 2011 editorial, Bruce Newman commented on reports from both ARC and BSI about their success in reducing reactions. Anne Eder and others at ARC introduced a process to encourage 16–18-year-old donors to drink 16 ounces of water before donation, and to perform applied muscle tension (AMT; in this case, leg lifting) during the donation process. They also focused on skilled staffing at drives with young donors. The rate of presyncope in these young donors was reduced by 21%, and the syncope rate was reduced by 4%, with no change in donor injury rate. Peter Tomasulo led a project for BSI, focusing on 17–22-year-old donors. In addition to restrictions on blood volume of donors, this group also encouraged muscle tension exercises in legs, starting at phlebotomy, and offered up to 500 mL (approximately 16 ounces) of water. Received: 3 May 2021 Accepted: 3 May 2021