265
Views
8
CrossRef citations to date
0
Altmetric
Original Articles

Reproducibility of the CO rebreathing technique with a lower CO dose and a shorter rebreathing duration at sea level and at 2320 m of altitude

, , , ORCID Icon, , & show all
Pages 590-599 | Received 08 Mar 2020, Accepted 30 Aug 2020, Published online: 21 Sep 2020
 

Abstract

Total hemoglobin mass (Hbmass) is routinely assessed in studies by the carbon monoxide (CO) rebreathing. Its clinical application is often hindered due to the consequent rise in carboxyhemoglobin (%HbCO) and the concern of CO toxicity. We tested the reproducibility of the CO rebreathing with a CO dose of 0.5 mL/kg body mass (CO0.5) compared to 1.5 mL/kg (CO1.5) and when shortening the CO rebreathing protocol. Therefore, CO rebreathing was performed 1×/day in eight healthy individuals on four consecutive days. On each day, either CO0.5 (CO0.5-1 and CO0.5-2) or CO1.5 (CO1.5-1 and CO1.5-2) was administered. Venous blood samples to determine %HbCO and quantify Hbmass were obtained prior to, and at 6 (T6), 8 (T8) and 10 min (T10) of CO rebreathing. This protocol was tested at sea level and at 2320 m to investigate the altitude-related measurement error. At sea level, the mean difference (95% limits of agreement) in Hbmass between CO0.5-1 and CO0.5-2 was 26 g (–26; 79 g) and between CO1.5-1 and CO1.5-2, it was 17 g (–18; 52 g). The respective typical error (TE) corresponded to 2.4% (CO0.5) and 1.5% (CO1.5), while it was 6.5% and 3.0% at 2320 m. With CO0.5, shortening the CO rebreathing resulted in a TE for Hbmass of 4.4% (T8 vs. T10) and 14.1% (T6 vs T10) and with CO1.5, TE was 1.6% and 5.8%. In conclusion, the CO dose and rebreathing time for the CO rebreathing procedure can be decreased at the cost of a measurement error ranging from 1.5-14.1%.

Acknowledgements

The authors would like to thank all participants for their commitment and time investment in this study.

Disclosure statement

No potential conflict of interest was reported by the author(s).

Additional information

Funding

This study was funded by the Partnership for Clean Competition PCC [grant ID 100100 R318] and partly funded by the World Anti-Doping Agency (WADA). The Centre for Physical Activity Research (CFAS) is supported by TrygFonden [grants ID 101390 and ID 20045].

Reprints and Corporate Permissions

Please note: Selecting permissions does not provide access to the full text of the article, please see our help page How do I view content?

To request a reprint or corporate permissions for this article, please click on the relevant link below:

Academic Permissions

Please note: Selecting permissions does not provide access to the full text of the article, please see our help page How do I view content?

Obtain permissions instantly via Rightslink by clicking on the button below:

If you are unable to obtain permissions via Rightslink, please complete and submit this Permissions form. For more information, please visit our Permissions help page.