Pulmonary, Allergy, and Critical Care Division, Department of Medicine, Hospital of the University of Pennsylvania, Philadelphia, Pennsylvania; Palliative and Advanced Illness Research Center, Department of Medicine, Hospital of the University of Pennsylvania, Philadelphia, Pennsylvania; and Leonard Davis Institute of Health Economics, University of Pennsylvania, Philadelphia, Pennsylvania.
Palliative and Advanced Illness Research Center, Department of Medicine, Hospital of the University of Pennsylvania, Philadelphia, Pennsylvania; Leonard Davis Institute of Health Economics, University of Pennsylvania, Philadelphia, Pennsylvania; Department of Biostatistics, Epidemiology, and Informatics, University of Pennsylvania School of Medicine, Philadelphia, Pennsylvania; and Department of Anesthesiology and Critical Care, Hospital of the University of Pennsylvania, Philadelphia, Pennsylvania.
Respir Care. 2022 Dec;67(12):1499-1507. doi: 10.4187/respcare.09769. Epub 2022 Jun 3.
Pulse oximetry is the mainstay of patient oxygen monitoring. Measurement error from pulse oximetry is more common for those with darker skin pigmentation, yet this topic remains understudied, and evidence-based clinical mitigation strategies do not currently exist. Our objectives were to measure the rate of occult hypoxemia, defined as arterial oxygen saturation (S ) < 88% when pulse oximeter oxygen saturation was between 92-96%, in a racially diverse critically ill population; to analyze degree, direction, and consistency of measurement error; and to develop a mitigation strategy that minimizes occult hypoxemia in advance of technological advancements.
We performed a multi-center retrospective cohort study of critically ill subjects.
Among 105,467 paired observations from 7,693 subjects, we found occult hypoxemia was more common among minority subjects. The frequency of occult hypoxemia was 7.9% versus 2.9% between Black and white subjects, respectively, ( < .001). Pulse oximeter measurement errors were inconsistent throughout a patient encounter, with 67% of encounters having a range of intra-subject measurement errors > 4 percentage points. In 75% of encounters, the intra-subject errors were bidirectional. S < 88% was less common at higher pulse oximeter oxygenation ranges (4.1% and 1.8% of observations among Black and white subjects at a pulse oximeter threshold of 94-98%). Although occult hypoxemia was further reduced at oxygenation saturation range 95-100%, the frequency of hyperoxemia (partial pressure of arterial oxygen > 110 mm Hg) became more common, occurring in 42.3% of Black and 46.0% of white observations.
Measurement error in pulse oximetry is common for all racial groups, but occult hypoxemia occurred most commonly in Black subjects. The highly variable magnitude and direction of measurement error preclude an individualized mitigation approach. In advance of technological advancements, we recommend targeting a pulse oximetry saturation goal of 94-98% for all patients.
脉搏血氧仪是患者氧监测的主要手段。对于肤色较深的人，脉搏血氧仪的测量误差更为常见，但这个问题的研究还不够充分，也没有基于证据的临床缓解策略。我们的目标是测量种族多样化的危重症患者中隐匿性低氧血症的发生率，定义为脉搏血氧饱和度仪氧饱和度在 92-96%之间时动脉血氧饱和度（S ）<88%；分析测量误差的程度、方向和一致性；并在技术进步之前制定一项缓解策略，以最大限度地减少隐匿性低氧血症。
我们对危重症患者进行了一项多中心回顾性队列研究。
在 7693 名患者的 105467 对配对观察中，我们发现隐匿性低氧血症在少数族裔患者中更为常见。黑人和白人患者中隐匿性低氧血症的发生率分别为 7.9%和 2.9%（<0.001）。整个患者就诊过程中脉搏血氧仪的测量误差不一致，67%的就诊患者个体内测量误差范围超过 4 个百分点。75%的就诊患者中，个体内误差是双向的。在脉搏血氧仪阈值为 94-98%时，S <88%的情况在较高的脉搏血氧仪氧饱和度范围内更为少见（黑人患者和白人患者的观察值中分别为 4.1%和 1.8%）。虽然在氧饱和度范围 95-100%时隐匿性低氧血症进一步减少，但高氧血症（动脉血氧分压>110mmHg）的频率变得更为常见，黑人患者中有 42.3%，白人患者中有 46.0%。
所有种族群体的脉搏血氧仪测量误差都很常见，但隐匿性低氧血症在黑人患者中最为常见。测量误差的幅度和方向变化很大，因此无法采用个体化缓解策略。在技术进步之前，我们建议所有患者的脉搏血氧饱和度目标值为 94-98%。
