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An Analysis of Exertional Safety After Blood Donation in Active Duty Military Personnel-A Feasibility Study.

INTRODUCTION
Whole blood (WB) is the optimal resuscitation fluid in hemorrhagic shock. Military research focuses on mortality benefits of WB acquired through walking blood banks (WBBs). Few military-based studies on donation effects exist, almost exclusively performed on small special operation forces. No Department of Defense regulations for postdonation precautions in nonaviation crew members exist. Further study is warranted regarding safety and limitations in postdonation populations.


MATERIALS AND METHODS
A feasibility (n = 25) prospective interventional study examined the safety of exertion (defined as a 1.6-km treadmill run at volunteers' minimum passing pace for the Army Physical Fitness Test) following 1 unit of WB donation. Subjects served as their own controls, performing baseline testing 7 days before donation, with repeat testing 1 h following donation conducted by Armed Services Blood Program personnel. Adverse events, pre- and postexertion vital signs (VS) were evaluated.


RESULTS
There were no adverse events throughout testing. Only resting heart rate (68 vs. 73 beats · min-1, p < 0.01) and postexertion heart rate were significantly different among pre- and postdonation VS. Additional significant findings were time to attain postexertion normocardia (116 vs. 147 seconds, p < 0.01). A small but statistically significant change in Borg perceived exertional scores was noted (10.3 vs. 10.8, p < 0.05).


CONCLUSIONS
This feasibility study demonstrates the first safety test of regular military populations performing exertion immediately following the standardized WB donation. VS changes may translate into a small but significant increase in perceived postdonation exertion. Future studies should expand duration and intensity of exertion to match combat conditions.