A randomized controlled pilot study of VO2 max testing: a potential model for measuring relative in vivo efficacy of different red blood cell products.
Journal Article (Journal Article)
BACKGROUND: Randomized trials, for example, RECESS, comparing "young" (median, 7-day) versus "middle-aged" (median, 28-day) red blood cells (RBCs), showed no difference in outcome. These data are important; however, they do not inform us about the safety and effectiveness of the oldest RBCs, which some patients receive. It may not be feasible to conduct a clinical trial randomizing patients to receive the oldest blood. Therefore, we propose strenuous exercise (VO2 max testing) as a model to study the relative efficacy to increase oxygen delivery to tissue of different RBC products, for example, extremes of storage duration. STUDY DESIGN AND METHODS: In this pilot study, eight healthy subjects had 2 units of leukoreduced RBCs collected by apheresis in AS-3 using standard methods. Subjects were randomized to receive both (2) units of their autologous RBCs at either 7 or 42 days after blood collection. VO2 max testing on a cycle ergometer was performed 2 days before (Monday) and 2 days after (Friday) the transfusion visit (Wednesday). This design avoids confounding effects on intravascular volume from the 2-unit blood transfusion. The primary outcome was the difference in VO2 max between Friday and Monday (delta VO2 max). RESULTS: VO2 max increased more in the 7-day RBC arm (8.7 ± 6.9% vs. 1.9 ± 6.5%, p = 0.202 for comparison between arms). Exercise duration (seconds) increased in the 7-day RBC arm (8.4 ± 1.7%) but actually decreased in the 42-day arm (-2.6 ± 3.6%, p = 0.002). CONCLUSIONS: This pilot study suggests that VO2 max testing has potential as a rigorous and quantitative in vivo functional assay of RBC function. Our preliminary results suggest that 42-day RBCs are inferior to 7-day RBCs at delivering oxygen to tissues.
Full Text
Duke Authors
Cited Authors
- Bennett-Guerrero, E; Lockhart, EL; Bandarenko, N; Campbell, ML; Natoli, MJ; Jamnik, VK; Carter, TR; Moon, RE
Published Date
- March 2017
Published In
Volume / Issue
- 57 / 3
Start / End Page
- 630 - 636
PubMed ID
- 27882555
Electronic International Standard Serial Number (EISSN)
- 1537-2995
Digital Object Identifier (DOI)
- 10.1111/trf.13918
Language
- eng
Conference Location
- United States