Air Liquide SA, Explor Center (Healthcare), Paris, Île-de-France, France.
IMMEDIAB Lab UMRS1138, Institut National de la Santé et de la Recherche Médicale (INSERM), Paris, France.
Diabetes Technol Ther. 2020 Jun;22(6):476-483. doi: 10.1089/dia.2019.0486. Epub 2020 Mar 18.
Continuous subcutaneous insulin infusion (CSII) is a widely adopted treatment for type 1 diabetes and is a component of an artificial pancreas. CSII accuracy is essential for glycemic control, however, this metric has not been given sufficient study, especially at the range of the lowest basal rates (BRs), which are commonly used in a pediatric population and in closed-loop systems (CLSs). Our study presents accuracy results of four off-the-shelf CSII systems using a new accurate method for CSII system evaluation. The accuracy of four off-the-shelf CSII systems was assessed: Medtronic MiniMed 640G, Ypsomed YpsoPump, Insulet Omnipod, and Tandem t:slim X2. The assessment was performed using a double-measurement approach through a direct mass flow meter and a time-stamped microgravimetric test bench combined with a Kalman mathematical filter. CSII accuracy was evaluated using mean of dose error. Mean absolute relative difference (MARD) of error was calculated at different observation windows over the whole series of tests. Peakwise insulin deliverance was assessed regarding stroke regularity in terms of frequency and volume. Mean error values indicate a general tendency to underdeliver with up to -16%. MARD of error shows very wide results for each pump and each BR from 7.4% (2 UI/h) to 61.3% (0.1 UI/h). Peakwise analysis shows several choices for BR adaptation (frequency for Omnipod, volume for Tandem, both for YpsoPump and MiniMed 640G). Precision in interstroke time appears to be better (standard deviation [SD] at 0.1 UI/h: 4.6%-12.9%) than stroke volume precision (SD at 0.1 UI/h 38.3%-46.4%). The accuracy of four off-the-shelf CSII systems is model and BR dependent. CSII imprecision could be due to a variability in volume and/or frequency of strokes for every pump. Some models appear better adapted for the smallest insulin needs, or for inclusion in a CLS. The clinical implications of these delivery errors on glucose instability must be evaluated.
持续皮下胰岛素输注（CSII）是 1 型糖尿病的广泛采用的治疗方法，也是人工胰腺的组成部分。CSII 的准确性对于血糖控制至关重要，但是，这个指标尚未得到充分研究，尤其是在最底层基础率（BR）范围内，这在儿科人群和闭环系统（CLS）中经常使用。我们的研究使用一种新的 CSII 系统精确评估方法，介绍了四种现成的 CSII 系统的准确性结果。评估了四种现成的 CSII 系统的准确性：美敦力 MiniMed 640G、Ypsomed YpsoPump、Insulet Omnipod 和 Tandem t:slim X2。评估是通过直接质量流量计和带有 Kalman 数学滤波器的时间戳微重力测试台的双测量方法进行的。CSII 准确性是通过剂量误差的平均值来评估的。在整个测试系列中，在不同的观察窗口计算了误差的平均绝对相对差异（MARD）。根据频率和体积，评估了峰值胰岛素输送的规律性。平均误差值表明存在普遍的输送不足趋势，最大可达-16%。每个泵和每个 BR 的误差 MARD 结果非常广泛，从 7.4%（2 UI/h）到 61.3%（0.1 UI/h）。峰值分析显示了 BR 适应的几种选择（对于 Omnipod 为频率，对于 Tandem 为体积，对于 YpsoPump 和 MiniMed 640G 为两者）。在两个冲程之间的时间的精度似乎更好（0.1 UI/h 的标准偏差 [SD]：4.6%-12.9%），而冲程体积的精度（0.1 UI/h 的 SD 38.3%-46.4%）。四种现成的 CSII 系统的准确性取决于型号和 BR。CSII 的不精确性可能是由于每个泵的冲程体积和/或频率的变化引起的。一些模型似乎更适合最小的胰岛素需求，或用于纳入 CLS。必须评估这些输送误差对葡萄糖不稳定性的临床影响。
