Effect of skin tone on the accuracy of the estimation of arterial oxygen saturation by pulse oximetry

Authors

Daniel Martin, Peninsula Medical School
Chris Johns
Lexy Sorrell, Peninsula Medical School
Eugene Healy
Mandeep Phull
Segun Olusanya
Mark Peters
Jeremy Fabes, Peninsula Medical School

ORCID

• Martin, Daniel: 0000-0001-6220-8235

Abstract

Background: Pulse oximetry-derived oxygen saturation (SpO₂) is an estimate of true arterial oxygen saturation (SaO₂). The aim of this review was to evaluate available evidence determining the effect of skin tone on the ability of pulse oximeters to accurately estimate SaO₂. Methods: Published literature was screened to identify clinical and non-clinical studies enrolling adults and children when SpO₂ was compared with a paired co-oximetry SaO₂ value. We searched literature databases from their inception to March 20, 2023. Risk of bias (RoB) was assessed using the QUADAS-2 tool. Certainty of assessment was evaluated using the GRADE tool. Results: Forty-four studies were selected reporting on at least 222 644 participants (6121 of whom were children) and 733 722 paired SpO₂–SaO₂ measurements. Methodologies included laboratory studies, prospective clinical, and retrospective clinical studies. A high RoB was detected in 64% of studies and there was considerable heterogeneity in study design, data analysis, and reporting metrics. Only 11 (25%) studies measured skin tone in 2353 (1.1%) participants; the remainder reported participant ethnicity: 68 930 (31.0%) participants were of non-White ethnicity or had non-light skin tones. The majority of studies reported overestimation of SaO₂ by pulse oximetry in participants with darker skin tones or from ethnicities assumed to have darker skin tones. Several studies reported no inaccuracy related to skin tone. Meta-analysis of the data was not possible. Conclusions: Pulse oximetry can overestimate true SaO₂ in people with darker skin tones. The clinical relevance of this bias remains unclear, but its magnitude is likely to be greater when SaO₂ is lower. Systematic review protocol: International Prospective Register of Systematic Reviews (PROSPERO): CRD42023390723.

DOI

10.1016/j.bja.2024.01.023

Publication Date

2024-05-01

Publication Title

British Journal of Anaesthesia

Volume

132

Issue

5

ISSN

0007-0912

Organisational Unit

Peninsula Medical School

Recommended Citation

Martin, D., Johns, C., Sorrell, L., Healy, E., Phull, M., Olusanya, S., Peters, M., & Fabes, J. (2024) 'Effect of skin tone on the accuracy of the estimation of arterial oxygen saturation by pulse oximetry', British Journal of Anaesthesia, 132(5). Available at: https://doi.org/10.1016/j.bja.2024.01.023