Poets C F, Southall D P
Department of Paediatric Pulmonology, Medizinische Hochschule, Hannover, Germany.
Pediatrics. 1994 May;93(5):737-46.
To review the technical principles of transcutaneous PO2 (tcPO2) monitors and pulse oximeters and to discuss methodological and practical issues related to the use of these devices in infants and children.
Literature review and summary of personal experience.
tcPO2 measurements are influenced by skin thickness, sensor temperature, amount of contact gel used, and state of peripheral perfusion. The average in vivo response time to a rapid decrease in PaO2 is approximately 16 seconds. Sensitivity to both hypoxemia (PaO2 < 50 mm Hg) and hyperoxemia (PaO2 > 80 to 100 mm Hg) is approximately 85%. Pulse oximeters require careful sensor placement (to avoid optical shunts) and adequate pulse pressures (> 20 mm Hg). They are prone to movement artifact. There are considerable differences in bias and precision between different brands, resulting, for example, in quite different upper alarm limits required to detect hyperoxemia reliably. The normal range of oxygen saturation measured by pulse oximetry, measured with one brand of pulse oximeter (Nellcor) during regular breathing, is 95% to 100% in preterm infants and 97% to 100% in full-term infants and children.
Because both devices have their specific shortfalls, they should ideally be used in combination, particularly in critically ill preterm neonates. Where this is not feasible or necessary, clinicians must be aware of the limitations of the device they are using.
回顾经皮氧分压（tcPO2）监测仪和脉搏血氧饱和度仪的技术原理，并讨论在婴幼儿中使用这些设备的方法学和实际问题。
文献综述及个人经验总结。
tcPO2测量受皮肤厚度、传感器温度、所用接触凝胶量以及外周灌注状态的影响。对PaO2快速下降的体内平均反应时间约为16秒。对低氧血症（PaO2 < 50 mmHg）和高氧血症（PaO2 > 80至100 mmHg）的敏感度约为85%。脉搏血氧饱和度仪需要仔细放置传感器（以避免光学分流）和足够的脉压（> 20 mmHg）。它们容易出现运动伪像。不同品牌之间在偏差和精度上存在相当大的差异，例如，导致可靠检测高氧血症所需的上限报警值有很大不同。使用一种品牌的脉搏血氧饱和度仪（Nellcor）在正常呼吸时测量的血氧饱和度正常范围，早产儿为95%至100%，足月儿和儿童为97%至100%。
由于这两种设备都有其特定的不足，理想情况下应联合使用，尤其是在危重新生儿中。如果不可行或没有必要，临床医生必须了解他们所使用设备的局限性。
