Bioingeniøren (Dec 2023)
Incidence of vasovagal syncope among blood donors – experiences from a Norwegian blood bank
Abstract
Background/ objective: Vasovagal reactions related to blood donation are often mild or moderate, but severe reactions such as syncope can occur. This study sought to investigate the incidence of syncope among blood donors in a Norwegian blood bank and to examine whether demographics and the timing of donation influenced the syncopal reactions experienced by donors. Methods: A retrospective study of blood donors who had experienced syncope in 2014-2018 at the Blood bank in Akershus University Hospital, Norway. The data consisted of syncope reports submitted to the hemovigilance system, supplemented by data available in donor database. Data were analyzed by chi-square test and Mann-Whitney U-test. Results: The results showed a low incidence of syncope during the study period: 0,08 % or 50 syncope per 62208 whole blood donations. For male and female repeat donors the results were 0.04% and 0.06%, respectively, and for first-time donors 0.48% and 0.32%, respectively. Only 50 % of the donors who were still eligible subsequently returned to donate, of which first-time donors constituted only 31 %. The timing of donation seems to affect the risk to experience syncope, with decreasing risk during afternoon and the evening. Conclusion: We found low incidence of syncope among our givers. The incidence varied by donor status and age, it was higher among first-time and younger donors. Diurnal variation in baroreceptor sensitivity may explain the association between timing of donation and occurrence of syncope.
