Objective

Evaluation of the reliability of pulse oximetry at four different attachment sites compared to haemoglobin oxygen saturation measured by a co-oximeter and calculated by a blood gas analyser in immobilized impala.

Study design

Randomized crossover study.

Animals

A total of 16 female impala.

Methods

Impala were immobilized with etorphine or thiafentanil alone, or etorphine in combination with a novel drug. Once immobilized, arterial blood samples were collected at 5 minute intervals for 30 minutes. Then oxygen was insufflated (5 L minute⁻¹) intranasally at 40 minutes and additional samples were collected. A blood gas analyser was used to measure the arterial partial pressure of oxygen and calculate the oxygen haemoglobin saturation (cSaO₂); a co-oximeter was used to measure the oxygen haemoglobin saturation (SaO₂) in arterial blood. Pulse oximeter probes were attached: under the tail, to the pinna (ear) and buccal mucosa (cheek) and inside the rectum. Pulse oximeter readings [peripheral oxygen haemoglobin saturation (SpO₂) and pulse quality] were recorded at each site and compared with SaO₂ and cSaO₂ using Bland-Altman and accuracy of the area root mean squares (A_rms) methods to determine the efficacy. P value < 0.05 was considered significant.

Results

Pulse quality was ‘good’ at each attachment site. SpO₂ measured under the tail was accurate and precise but only when SaO₂ values were above 90% (bias = 3, precision = 3, A_rms = 4). The ear, cheek and rectal probes failed to give accurate or precise readings (ear: bias = −4, precision = 14, A_rms = 15; cheek: bias = 12, precision = 11, A_rms = 16; and rectum: bias = 5, precision = 12, A_rms = 13).

Conclusions and clinical relevance

In order to obtain accurate and precise pulse oximetry readings in immobilized impala, probes must be placed under the tail and SaO₂ must be above 90%. Since SaO₂ values are usually low in immobilized impala, pulse oximeter readings should be interpreted with caution.

中文翻译：

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评估脉搏血氧仪在不同附着部位的可靠性，以检测固定化黑斑羚（Aepyceros melampus）中的低氧血症。

目的

与通过共血氧仪测量并由固定式黑斑羚中的血气分析仪计算出的血红蛋白氧饱和度相比，评估了四个不同附着部位的脉搏血氧饱和度的可靠性。

学习规划

随机交叉研究。

动物

共有16只雌性黑斑羚。

方法

Impala单独用埃托啡或噻芬太尼固定，或与新药联用依托啡固定化。固定后，每隔5分钟收集一次动脉血样本，持续30分钟。然后在40分钟鼻内吹入氧气（5 L min ^-1），并收集另外的样品。使用血气分析仪测量氧气的动脉分压并计算氧气血红蛋白饱和度（cSaO ₂）。用血氧饱和度计测量动脉血中的氧血红蛋白饱和度（SaO ₂）。脉搏血氧仪探头连接：在尾巴下方，耳廓（耳）和颊粘膜（颊）以及直肠内部。脉搏血氧饱和度读数[周围血氧饱和度（SpO ₂）和脉搏质量]记录在每个部位，并使用Bland-Altman和面积_均方根（A _rms）方法的准确性与SaO ₂和cSaO ₂进行比较，以确定疗效。P值＜0.05被认为是显着的。

结果

每个附件部位的脉冲质量均良好。在尾部下测量的SpO ₂准确而精确，但仅当SaO ₂值高于90％时（偏差= 3，精度= 3，_有效值 = 4）。耳朵，脸颊和直肠探针无法提供准确或精确的读数（耳朵：偏差= -4，精度= 14，_有效值 = 15;脸颊：偏差= 12，精度= 11，_有效值 = 16;直肠：偏差= 5，精度= 12，_均方根 = 13）。

结论与临床意义

为了在固定的黑斑羚中获得准确而精确的脉搏血氧饱和度读数，必须将探针放在尾部下方，并且SaO ₂必须高于90％。由于固定的黑斑羚中的SaO ₂值通常较低，因此应谨慎解释脉搏血氧仪的读数。