Timing of hypotensive adverse events in U.S. source plasma donors: Exploratory analysis from the IMPACT trial

Background and objectives: There is less robust data describing adverse events (AEs) in source plasma donors than in whole blood donors, particularly regarding time to AEs (TAEs). We, therefore, sought to characterize TAE and the influence of donor characteristics in a large-scale clinical trial dataset.

Materials and methods: TAE was calculated utilizing data from the IMPACT (IMproving PlasmA CollecTion) trial, with linear regression analyses performed to determine the influence of donor parameters on TAE.

Results: Linear regression revealed that repeat donors tended to have AEs ~6 min later than naïve donors in the IMPACT trial; however, this was not statistically significant (p = 0.781). Besides this, gender showed greatest difference in TAE; however, no covariates were statistically significant. AE rates were relatively constant throughout the donation process with higher rates beginning 40 min after initiation; no initial peak was observed (first 10-15 min).

Conclusion: AEs occurred throughout the donation process. None of the analyzed factors could fully explain the difference in the dynamics of AE timing with that of whole blood donation, particularly the missing early peak. Therefore, other factors, e.g., expectation and attitude towards donating plasma and potential events during plasma collection, may explain this difference and should be the focus of future studies.