Immediate effects of blood donation on physical and cognitive performance-A randomized controlled double-blinded trial.

BACKGROUND: The success of implementing damage control resuscitation principles pre-hospital has been at the expense of several logistic burdens including the requirements for resupply, and the question of donor safety during the development of whole blood programs. Previous studies have reported effects on physical performance after blood donation; however, none have investigated the effects of blood donation on cognitive performance.

METHOD: We describe a prospective double-blinded, randomized, controlled study comprised of a battery of tests: three cognitive tests, and VO2max testing on a cycle ergometer. Testing was performed 7 days before blinded donation (baseline day), immediately after donation (Day 0), and 7 days (Day 7) after donation. The inclusion criteria included being active blood donors at the Haukeland University Hospital blood bank, where eligibility requirements were met on the testing days, and providing informed consent. Participants were randomized to either the experimental (n = 26) or control group (n = 31). Control group participants underwent a 'mock donation" in which a phlebotomy needle was placed but blood was not withdrawn.

RESULTS: In the experimental group, mean ± SEM VO2max declined 6% from 41.35 ± 1.7 mLO2/(min·kg) at baseline to 39.0 ± 1.6 mLO2/(min·kg) on Day 0 and increased to 40.51 ± 1.5 mLO2/(min·kg) on Day 7. Comparable values in the control group were 42.1 ± 1.8 mLO2/(min·kg) at baseline, 41.6 ± 1.8 mLO2/(min·kg)) on Day 1 (1% decline from baseline), and 41.8 ± 1.8 mLO2/(min·kg) on Day 7.Comparing scores of all three cognitive tests on Day 0 and Day 7 showed no significant differences (p > 0.05).

CONCLUSION: Our main findings are that executive cognitive and physical performances were well maintained after whole blood donation in healthy blood donors. The findings inform postdonation guidance on when donors may be required to return to duty.

LEVEL OF EVIDENCE: Randomized, controlled, double-blinded prospective trial study, level 1.