Skip to main page content
U.S. flag

An official website of the United States government

Dot gov

The .gov means it’s official.
Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you’re on a federal government site.

Https

The site is secure.
The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.

Access keys NCBI Homepage MyNCBI Homepage Main Content Main Navigation
. 2025 Aug 1;53(8):e1610-e1619.
doi: 10.1097/CCM.0000000000006736. Epub 2025 Jun 16.

Pulse Oximetry and Arterial Blood Gas Oxygen Saturation Discrepancies and Mortality in Extracorporeal Cardiopulmonary Resuscitation Patients: An Extracorporeal Life Support Organization Registry Analysis

Andrew Kalra  1   2 , Christopher Wilcox  3 , Winnie Liu  1 , Shi Nang Feng  1 , Patricia Brown  1 , Bo Soo Kim  4 , Daniel Brodie  5 , Glenn J R Whitman  1 , Sung-Min Cho  1   6 ; Hopkins Exploration, Research, and Advancement in Life support Devices (HERALD) Group
Collaborators, Affiliations

Pulse Oximetry and Arterial Blood Gas Oxygen Saturation Discrepancies and Mortality in Extracorporeal Cardiopulmonary Resuscitation Patients: An Extracorporeal Life Support Organization Registry Analysis

Andrew Kalra et al. Crit Care Med. .

Abstract

Objectives: Previous studies have shown that inaccurate peripheral oxygen saturation (Sp o2 ) readings compared with arterial oxygen saturation (Sa o2 ) may occur in extracorporeal membrane oxygenation (ECMO) patients. We hypothesized that a greater Sp o2 -Sa o2 discrepancy in extracorporeal cardiopulmonary resuscitation (ECPR) patients is associated with higher mortality due to unrecognized hypoxemia.

Design: Retrospective analysis.

Setting: Data within the Extracorporeal Life Support Organization Registry from 496 ECMO centers (2018-2024).

Patients: Patients 18 years old or older receiving ECPR (first-run only).

Interventions: None.

Measurements and main results: Laboratory measurements including Sp o2 -Sa o2 were measured at 24 hours of ECMO support. Acute brain injury (ABI) included hypoxic-ischemic brain injury, ischemic stroke, intracranial hemorrhage, and seizures. Based on an inflection point in cubic spline analysis, a Sp o2 -Sa o2 threshold greater than or equal to 4% was used as a binary variable to assess its association with in-hospital mortality. Three thousand nine hundred seventy ECPR patients (median age, 57 yr; 71% male) were included. The median ECMO duration was 4 days (interquartile range, 2-7 d). There were 634 patients (16%) with Sp o2 -Sa o2 greater than or equal to 4% and 3336 (84%) with Sp o2 -Sa o2 less than 4%. Overall mortality was 60% ( n = 2391). Patients with Sp o2 -Sa o2 greater than or equal to 4% had higher mortality compared with patients with Sp o2 -Sa o2 less than 4% (67%, n = 425 vs. 59%, n = 1966; p < 0.001). Patients with Sp o2 -Sa o2 greater than or equal to 4% had higher serum lactate values than those with Sp o2 -Sa o2 less than 4% (3.1 vs. 2.8 mmol/L; p = 0.0017). In multivariable logistic regression adjusted for preselected covariates, Sp o2 -Sa o2 greater than or equal to 4% was associated with increased risk of mortality (adjusted odds ratio [aOR], 1.39; 95% CI, 1.13-1.71). Additional risk factors associated with higher mortality included ABI (aOR, 5.81; 95% CI, 4.70-7.20), hyperoxemia greater than or equal to 300 mm Hg (aOR, 1.93; 95% CI, 1.53-2.43), hyperoxemia 200-299 mm Hg (aOR, 1.76; 95% CI, 1.37-2.25), gastrointestinal hemorrhage (aOR, 1.69; 95% CI, 1.42-2.00), renal replacement therapy (aOR, 1.48; 95% CI, 1.03-2.11), hypoxemia less than 60 mm Hg (aOR, 1.45; 95% CI, 1.00-2.10), older age (aOR, 1.19; 95% CI, 1.13-1.26), and higher lactate (aOR, 1.17; 95% CI, 1.13-1.20). Race/ethnicity was not associated with higher mortality.

Conclusions: Sp o2 -Sa o2 greater than or equal to 4% in the first 24 hours after ECPR is associated with increased risk of mortality, potentially due to unrecognized hypoxemia, irrespective of race/ethnicity.

Keywords: Extracorporeal Life Support Organization Registry; extracorporeal cardiopulmonary resuscitation; extracorporeal membrane oxygenation; mortality; pulse oximetry.

PubMed Disclaimer

Conflict of interest statement

Dr. Brodie received funding from LivaNova, Medtronic, Inspira, Cellenkos, HBOX Therapies, and UpToDate; he is the President-elect of the Extracorporeal Life Support Organization and the Chair of the Board of the International Extracorporeal Membrane Oxygenation Network; and he writes for UpToDate. Dr. Whitman received funding from Cellphire Therapeutics/PPD Development LP and GWBN LLC; he disclosed that he owns 50% of GWBN LLC; and he was supported by the National Institute of Neurological Disorders and Stroke (1R21NS135045). Dr. Cho received support for article research from the National Institutes of Health (1K23HL157610; 1R21NS135045) and Defense Advanced Research Projects Agency (HR001124S0024). The remaining authors have disclosed that they do not have any potential conflicts of interest.

References

    1. Louw A, Cracco C, Cerf C, et al.: Accuracy of pulse oximetry in the intensive care unit. Intensive Care Med 2001; 27:1606–1613
    1. Valbuena VSM, Seelye S, Sjoding MW, et al.: Racial bias and reproducibility in pulse oximetry among medical and surgical inpatients in general care in the Veterans Health Administration 2013-19: Multicenter, retrospective cohort study. BMJ 2022; 378:e069775
    1. Sjoding MW, Dickson RP, Iwashyna TJ, et al.: Racial bias in pulse oximetry measurement. N Engl J Med 2020; 383:2477–2478
    1. Silverston P, Ferrari M, Quaresima V: Pulse oximetry in primary care: Factors affecting accuracy and interpretation. Br J Gen Pract 2022; 72:132–133
    1. U. S. Food and Drug Administration: FDA Safety Communication: Pulse Oximeter Accuracy and Limitations. 2021. Available at: https://www.fda.gov/medical-devices/safety-communications/pulse-oximeter... . Accessed January 31, 2023

LinkOut - more resources