Trends in return behavior after an adverse event in Australian whole blood and plasma donors

Background: This study examined the impact of donor adverse events (DAEs) on plasma donor return and compared these against trends in whole blood (WB) donors. Study Design and Methods: Using a retrospective cohort design, donors who attempted to give plasma or WB in 2014-2015 were categorized by DAE and followed for 2 years. Analyses of return rate, time to return, subsequent donation frequency, and recurrent risk were performed. Donor characteristics associated with return were also assessed. Results: For both plasma and WB donors, vasovagal reactions (VVRs) were the strongest deterrent to return, with a lower proportion returning, taking longer to return, and making fewer subsequent donations than those with uncomplicated donations. Despite a higher likelihood of a recurrent event among those who experienced a DAE, the majority had an uncomplicated subsequent donation. Donor characteristics associated with return varied by phlebotomy and DAE type. For donors experiencing a VVR, differences were observed by donor experience, age, sex, and site type between plasma and WB. For phlebotomy-injured donors, differences were observed by sex, blood type, donor experience, and donation outcome between the two groups. No factors associated with return after a citrate reaction were found. Conclusion: This study highlights the detrimental effects of DAEs on plasma return, in particular VVRs, and the differences in factors associated with return compared to WB donors. Further research is required to understand the mechanisms underlying the decision to return following a DAE