Fear of blood draw and total draw time combine to predict vasovagal reactions among whole blood donors.

Background: Fear of blood draws is a predictor of vasovagal reaction risk among whole blood donors, and this relationship is particularly evident among less experienced donors. This study examines the combined effect of donor fear and total blood draw time on vasovagal reactions.
Study Design and Methods: After successfully completing the blood donor health screening, 2730 whole blood donors attending high school drives were asked about their fear of having blood drawn. Donor reports of fear versus no fear were combined with total blood draw time to predict phlebotomist ratings of donor vasovagal reactions.
Results: Both fear and draw time were significant predictors of vasovagal reactions, with observed reaction rates of 31.2% for fearful donors whose blood draw lasted 10 minutes or more versus 5.0% for nonfearful donors whose draw lasted less than 6 minutes. Binomial regression analyses revealed that fear remained a significant predictor of reaction rates across all blood draw intervals examined (odds ratio, 2.8-4.1; all p < 0.001) and that these effects were maintained after controlling for donor sex, weight, estimated blood volume, pulse rate, and donation status.
Conclusion: This report shows that both fear and blood draw time increase vasovagal reaction rates, and the two are additive. These findings suggest that fearful donors should be the focus of special attention to reduce their distress before donation as well as careful observation throughout the draw.
(© 2015 AABB.)