Hughes Caroline, Chen Danni, Law Tyler, Bickler Philip, Feiner John, Shmuylovich Leonid, Behnke Ella, Ortiz Lily, Leeb Gregory, Auchus Isabella, Negussie Fekir, Bisegerwa Ronald, Zamora René Vargas, Igaga Elizabeth, Moore Kelvin, Okunlola Olubunmi, Monk Ellis, Fernandez Jana Lyn, Ehie Odinakachukwu, Wilks Bernadette, Oyefeso Koyinsola, Schornack Deleree, Sendagire Cornelius, Lipnick Michael S
University of California San Francisco Hypoxia Research Laboratory.
Department of Anesthesia and Perioperative Care, University of California San Francisco.
medRxiv. 2025 Aug 13:2025.08.11.25332026. doi: 10.1101/2025.08.11.25332026.
The International Organization for Standardization (ISO) and US Food and Drug Administration (FDA) are updating standards and guidance for pulse oximeters to reduce performance disparities linked to skin pigment. We tested common oximeters with current and anticipated regulatory frameworks. We hypothesized that most oximeters would show more positive bias in darkly vs lightly pigmented participants and that fewer oximeters would 'pass' anticipated regulations.
We used a controlled desaturation protocol to test 34 oximeters across arterial oxygen saturations (SaO) 70-100% in healthy adults. Based on what FDA and ISO had shared at the time of study design, we studied cohort sizes of > 24 with > 25% of participants being darkly pigmented. We used the subjective Monk Skin Tone (MST) scale and the objective individual typology angle (ITA) derived from a spectrophotometer to characterize skin pigment. The root mean square error (A), bias (mean of SpO - SaO error), and skin pigment differential bias were calculated. Monte Carlo simulation explored potential impacts of participant selection on device passing.
For cohorts of 24 participants, 28/34 oximeters passed 2017 ISO Standard A < 4%, 22/34 passed 2013 FDA guidance A < 3%, 21/34 oximeters passed both A and differential bias criteria for anticipated ISO standards, and 1/34 passed anticipated FDA criteria. More devices passed with cohorts > 24. Eleven oximeters had more positive bias in participants with dark vs. light (dorsal finger) pigmentation across 70-100% SaO. Eighteen devices could pass or fail depending on cohorts selected for analysis.
Pulse oximeters show variable performance across manufacturers and models, with only some devices showing more positive bias in people with darker skin. Anticipated updates to ISO and FDA frameworks yield strikingly different assessments and require refinement. Whether they will translate into improved real-world performance or reduced health disparities is yet to be determined.
国际标准化组织（ISO）和美国食品药品监督管理局（FDA）正在更新脉搏血氧仪的标准和指南，以减少与皮肤色素相关的性能差异。我们使用当前和预期的监管框架对常见的血氧仪进行了测试。我们假设，与肤色浅的参与者相比，大多数血氧仪在肤色深的参与者中会表现出更大的正向偏差，并且符合预期法规的血氧仪数量会更少。
我们采用了一种受控的去饱和方案，对34款血氧仪在70%至100%的动脉血氧饱和度（SaO）范围内对健康成年人进行了测试。根据FDA和ISO在研究设计时所提供的信息，我们研究了样本量大于24且肤色深的参与者占比超过25%的队列。我们使用主观的蒙克肤色（MST）量表和通过分光光度计得出的客观个体类型角度（ITA）来表征皮肤色素。计算了均方根误差（A）、偏差（SpO - SaO误差的平均值）以及皮肤色素差异偏差。蒙特卡洛模拟探讨了参与者选择对设备通过情况的潜在影响。
对于24名参与者的队列，28/34款血氧仪符合2017年ISO标准A<4%，22/34款符合2013年FDA指南A<3%，21/34款血氧仪同时符合预期ISO标准的A和差异偏差标准，1/34款符合预期FDA标准。样本量大于24时，更多设备通过测试。在70%至100%的SaO范围内，11款血氧仪在肤色深（手指背部）与肤色浅的参与者中表现出更大的正向偏差。18款设备的通过与否取决于所选择用于分析的队列。
脉搏血氧仪在不同制造商和型号之间表现出不同的性能，只有部分设备在肤色较深的人群中表现出更大的正向偏差。ISO和FDA框架的预期更新产生了截然不同的评估结果，需要进一步完善。它们是否会转化为实际性能的提升或健康差异的减少还有待确定。
