Modelling the distribution of the oxygen-haemoglobin dissociation curve in vivo: An observational study

Crooks, Colin J.; West, Joe; Morling, Joanne R.; Simmonds, Mark; Juurlink, Irene; Briggs, Steve; Cruickshank, Simon; Hammond-Pears, Susan; Shaw, Dominick; Card, Timothy R.; Fogarty, Andrew W.

Abstract

Few studies have explored the variability of the oxygen-haemoglobin dissociation curve in vivo.

96,428 blood gas measurements were obtained (80,376 arterial, 6959 venous) from a cohort of 7656 patients who were admitted to a large UK teaching hospital between 1 February 2020 and 31 December 2021 for a Covid-19 related admission with a positive PCR. There was consistent variation of the distribution of the oxygen-haemoglobin curve across most oxygen saturation strata with typical values at 91–92 % saturation (mean 8.1kPa, standard deviation sd 0.6 kPa or 60.8 mmHg sd 4.5 mmHg), with the exception of the highest strata of oxygen saturation of 99–100 % (mean 17.7 kPa, sd 8.1kPa or 132 mmHg sd 60.8).

The higher oxygen partial pressures at higher oxygen saturations are a concern in view of the increased mortality observed in RCTs of higher oxygen saturation targets. However, the observational study design precludes any attribution of causality.

Citation

Crooks, C. J., West, J., Morling, J. R., Simmonds, M., Juurlink, I., Briggs, S., Cruickshank, S., Hammond-Pears, S., Shaw, D., Card, T. R., & Fogarty, A. W. (2025). Modelling the distribution of the oxygen-haemoglobin dissociation curve in vivo: An observational study. Respiratory Physiology and Neurobiology, 333, Article 104400. https://doi.org/10.1016/j.resp.2025.104400

• Journal Article Type: Article
• Acceptance Date: Feb 1, 2025
• Online Publication Date: Feb 4, 2025
• Publication Date: 2025-04
• Deposit Date: Feb 5, 2025
• Publicly Available Date: Feb 5, 2025
• Journal: Respiratory Physiology and Neurobiology
• Print ISSN: 1569-9048
• Electronic ISSN: 1878-1519
• Publisher: Elsevier
• Peer Reviewed: Peer Reviewed
• Volume: 333
• Article Number: 104400
• DOI: https://doi.org/10.1016/j.resp.2025.104400
• Keywords: Oxygen; Haemoglobin; Mortality; COVID-19
• Public URL: https://nottingham-repository.worktribe.com/output/45038656
• Publisher URL: https://www.sciencedirect.com/science/article/pii/S1569904825000114?via%3Dihub