Objective

To compare values of haemoglobin concentration (SpHb), arterial haemoglobin saturation (SpO₂) and calculated arterial oxygen content (SpOC), measured noninvasively with a pulse co-oximeter before and after in vivo adjustment (via calibration of the device using a measured haemoglobin concentration) with those measured invasively using a spectrophotometric-based blood gas analyser in anaesthetized dogs.

Study design

Prospective observational clinical study.

Animals

A group of 39 adult dogs.

Methods

In all dogs after standard instrumentation, the dorsal metatarsal artery was catheterised for blood sampling, and a pulse co-oximeter probe was applied to the tongue for noninvasive measurements. Paired data for SpHb, SpO₂ and SpOC from the pulse co-oximeter and haemoglobin arterial oxygen saturation (SaO₂) and arterial oxygen content (CaO₂) from the blood gas analyser were obtained before and after in vivo adjustment. Bland–Altman analysis for repeated measurements was used to evaluate the bias, precision and agreement between the pulse co-oximeter and the blood gas analyser. Data are presented as mean differences and 95% limits of agreement (LoA).

Results

A total of 39 data pairs were obtained before in vivo adjustment. The mean invasively measured haemoglobin–SpHb difference was –2.7 g dL⁻¹ with LoA of –4.9 to –0.5 g dL⁻¹. After in vivo adjustment, 104 data pairs were obtained. The mean invasively measured haemoglobin–SpHb difference was –0.2 g dL⁻¹ with LoA of –1.1 to 0.6 g dL⁻¹. The mean SaO₂–SpO₂ difference was 0.86% with LoA of –0.8% to 2.5% and that between CaO₂–SpOC was 0.66 mL dL^–1 with LoA of –2.59 to 3.91 mL dL^–1.

Conclusions

Before in vivo adjustment, pulse co-oximeter derived values overestimated the spectrophotometric-based blood gas analyser haemoglobin and CaO₂ values. After in vivo adjustment, the accuracy, precision and LoA markedly improved. Therefore, in vivo adjustment is recommended when using this device to monitor SpHb in anaesthetised dogs.

中文翻译：

---

麻醉犬体内调整后脉搏血氧饱和度技术的评估

客观的

为了比较血红蛋白浓度 (SpHb)、动脉血红蛋白饱和度 (SpO ₂ ) 和计算的动脉氧含量 (SpOC) 的值，在体内调整之前和之后使用脉搏血氧计无创测量（通过使用测量的血红蛋白校准设备）浓度）与那些使用基于分光光度计的血气分析仪在麻醉狗中进行侵入性测量。

学习规划

前瞻性观察性临床研究。

动物

一组 39 只成年犬。

方法

在标准仪器后的所有狗中，背跖动脉插入导管进行血液采样，并将脉搏血氧仪探头应用于舌头进行无创测量。在体内调整前后获得来自脉搏血氧仪的SpHb、SpO ₂和 SpOC 和来自血气分析仪的血红蛋白动脉血氧饱和度 (SaO ₂ ) 和动脉氧含量 (CaO ₂ ) 的配对数据。重复测量的 Bland-Altman 分析用于评估脉搏血氧仪和血气分析仪之间的偏差、精度和一致性。数据表示为平均差异和 95% 的一致性限制 (LoA)。

结果

在体内调整之前总共获得了39个数据对。平均有创测量的血红蛋白-SpHb 差异为 –2.7 g dL ^-1，LoA 为 –4.9 至 –0.5 g dL ^-1。后在体内调节，获得104数据对。平均有创测量的血红蛋白-SpHb 差异为 –0.2 g dL ^-1，LoA 为 –1.1 至 0.6 g dL ^-1。SaO ₂ –SpO ₂的平均差异为 0.86%，LoA 为 –0.8% 至 2.5%，CaO ₂ –SpOC之间的差异为 0.66 mL dL ^–1，LoA 为 –2.59 至 3.91 mL dL ^–1。

结论

在体内调整之前，脉搏血氧仪得出的值高估了基于分光光度法的血气分析仪血红蛋白和 CaO ₂值。后在体内调整，准确度，精密度和协议书显着提高。因此，在使用该设备监测麻醉犬的 SpHb 时，建议进行体内调整。