Bangash Mansoor N, Hodson James, Evison Felicity, Patel Jaimin M, Johnston Andrew McD, Gallier Suzy, Sapey Elizabeth, Parekh Dhruv
Birmingham Acute Care Research Group, Institute of Inflammation and Ageing, New Queen Elizabeth Hospital, University of Birmingham, 1st Floor, Mindelsohn Way, Birmingham B15 2WB, United Kingdom.
Department of Critical Care, University Hospitals Birmingham NHS Foundation Trust, Birmingham, United Kingdom.
EClinicalMedicine. 2022 May 6;48:101428. doi: 10.1016/j.eclinm.2022.101428. eCollection 2022 Jun.
Pulse oximeters are routinely used in community and hospital settings worldwide as a rapid, non-invasive, and readily available bedside tool to approximate blood oxygenation. Potential racial biases in peripheral oxygen saturation (SpO2) measurements may influence the accuracy of pulse oximetry readings and impact clinical decision making. We aimed to assess whether the accuracy of oxygen saturation measured by SpO2, relative to arterial blood gas (SaO2), varies by ethnicity.
In this large retrospective observational cohort study covering four NHS Hospitals serving a large urban population in Birmingham, United Kingdom, consecutive pairs of SpO2 and SaO2 measurements taken on the same patient within an interval of less than 20 min were identified from electronic patient records. Where multiple pairs of measurements were recorded in a spell, only the first was included in the analysis. The differences between SpO2 and SaO2 measurements were compared across groups of self-identified ethnicity. These differences were subsequently adjusted for age, sex, bilirubin, systolic blood pressure, carboxyhaemaglobin saturations and the time interval between SpO2 and SaO2 measurements.
Paired O2 saturation measurements from 16,818 inpatient spells between 1st January 2017 and 18th February 2021 were analysed. The cohort self-identified as being of White (81.2%), Asian (11.7%), Black (4.0%), or Other (3.2%) ethnicities. Across the cohort, SpO2 was statistically significantly higher than SaO2 ( < 0.0001), with medians of 98% (interquartile range [IQR]: 95-100%) vs. 97% (IQR: 96-99%), and a median difference of 0.5% points (pps; 95% confidence interval [CI]: 0.5-0.6). However, the size of this difference varied considerably with the magnitude of SaO2, with SpO2 overestimating by a median by 3.8pp (IQR: 0.4, 8.8) for SaO2 values <90% but underestimating by a median of 0.4pp (IQR: -2.0, 1.4) for an SaO2 of 95%. The differences between SpO2 and SaO2 were also found to vary by ethnicity, with this difference being 0.8pp (95% CI: 0.6-1.0, < 0.0001) greater in those of Black vs. White ethnicity. These differences resulted in 8.7% vs. 6.1% of Black vs. White patients who were classified as normoxic on SpO2 actually being hypoxic on the gold standard SaO2 (odds ratio: 1.47, 95% CI: 1.09-1.98, = 0.012).
Pulse oximetry may overestimate O2 saturation, and this is possibly more pronounced in patients of Black ethnicity. Prospective studies are urgently warranted to assess the impact of ethnicity on the accuracy of pulse oximetry, to ensure care is optimised for all.
PIONEER, the Health Data Research UK (HDR-UK) Health Data Research Hub in acute care.
脉搏血氧仪在全球范围内的社区和医院环境中被常规使用，作为一种快速、无创且随时可用的床边工具来估算血液氧合情况。外周血氧饱和度（SpO2）测量中潜在的种族偏见可能会影响脉搏血氧饱和度读数的准确性，并影响临床决策。我们旨在评估相对于动脉血气（SaO2），SpO2测量的氧饱和度准确性是否因种族而异。
在这项大型回顾性观察性队列研究中，涵盖了为英国伯明翰市大量城市人口服务的四家国民保健服务（NHS）医院，从电子病历中识别出在同一患者身上于不到20分钟的间隔内连续进行的SpO2和SaO2测量值对。如果在一个时间段内记录了多对测量值，则仅将第一对纳入分析。对自我认定的不同种族组的SpO2和SaO2测量值之间的差异进行了比较。随后对这些差异进行了年龄、性别、胆红素、收缩压、碳氧血红蛋白饱和度以及SpO2和SaO2测量值之间的时间间隔的校正。
分析了2017年1月1日至2021年2月18日期间16818例住院病例的配对氧饱和度测量值。该队列自我认定为白人（81.2%）、亚洲人（11.7%）、黑人（4.0%）或其他种族（3.2%）。在整个队列中，SpO2在统计学上显著高于SaO2（<0.0001），中位数分别为98%（四分位间距[IQR]：95 - 100%）和97%（IQR：96 - 99%），中位数差异为0.5个百分点（pps；95%置信区间[CI]：0.5 - 0.6）。然而，这种差异的大小随SaO2的大小有很大变化，对于SaO2值<90%，SpO2中位数高估3.8pp（IQR：0.4，8.8），而对于SaO2为95%时，SpO2中位数低估0.4pp（IQR： - 2.0，1.4）。还发现SpO2和SaO2之间的差异因种族而异，黑人种族与白人种族相比，这种差异大0.8pp（95% CI：0.6 - 1.0，<0.0001）。这些差异导致在SpO2测量中被分类为氧合正常的黑人患者与白人患者中，实际在金标准SaO2测量下为低氧的比例分别为8.7%和6.1%（优势比：1.47，95% CI：1.09 - 1.98，=0.012）。
脉搏血氧仪可能会高估氧饱和度，这在黑人种族患者中可能更为明显。迫切需要进行前瞻性研究以评估种族对脉搏血氧仪准确性的影响，以确保为所有人优化护理。
先锋项目，英国健康数据研究（HDR - UK）急性护理健康数据研究中心。
