Abstract：
The aim of this prospective clinical study was to evaluate the efficacy of the Surgical Pleth Index (SPI), a validated nociception monitor in human anaesthesia, in dogs. The technology uses a plethysmographic signal from a specific pulse oximetry probe to analyse pulse wave amplitudes and heartbeat intervals. Twenty-six healthy dogs anaesthetised for castration were included. SPI, invasive mean arterial pressure (MAP) and heart rate (HR) were continuously monitored. The occurrence or resolution of a haemodynamic reaction (HDR), defined as a > 20% increase in HR and/or MAP, was assessed at predefined times: cutaneous incision, testicles\' exteriorization, cutaneous suture, and fentanyl administration. Following nociceptive events, the dogs presenting a HDR showed a significant 8% and 10% increase in SPI at 3 and 5 min respectively, whereas after fentanyl administration, a 13% and 16% significant decrease in SPI were noted. Receiver operating characteristic curves analysis indicated a moderate performance for the dynamic variations of SPI over 1 min to predict a HDR (AUC: 0.68, threshold value: +15%) or its resolution after fentanyl administration (AUC of 0.72, threshold value: -15%) within 3 min. The SPI varied according to perioperative nociceptive events and analgesic treatment; however, its performance to anticipate a HDR was limited with high specificity but low sensivity. Refinement of the algorithm to specifically accommodate for the canine species may be warranted. Further studies are required to evaluate the influence of other factors on the performance of this index.
摘要：
这项前瞻性临床研究的目的是评估手术指数（SPI）的疗效，人体麻醉中经过验证的伤害感受监测器，在狗。该技术使用来自特定脉搏血氧测量探头的体积描记信号来分析脉搏波振幅和心跳间隔。包括26只麻醉去势的健康狗。SPI,连续监测有创平均动脉压（MAP）和心率（HR）。血液动力学反应（HDR）的发生或消退，定义为HR和/或MAP增加>20%，在预定时间进行评估：皮肤切口，睾丸外化，皮肤缝合,和芬太尼给药。在伤害性事件之后，表现出HDR的狗在3和5分钟时SPI分别显着增加了8％和10％，而芬太尼给药后，观察到SPI显著下降13%和16%.接收器操作特征曲线分析表明，SPI在1分钟内的动态变化具有中等性能，可以预测3分钟内芬太尼给药后的HDR（AUC：0.68，阈值：+15％）或其分辨率（AUC为0.72，阈值：-15％）。SPI根据围手术期的伤害性事件和镇痛治疗而变化；然而，其预测HDR的性能受到限制,特异性高,但灵敏度低.可能需要改进算法以专门适应犬类。需要进一步研究以评估其他因素对该指标性能的影响。
