Flénet T, Fontecave-Jallon J, Guméry P-Y, Eynard C, Boucher F, Baconnier P, Tanguy S
Université Grenoble Alpes, CNRS, TIMC-IMAG Laboratory UMR 5525, PRETA team, F-38041 Grenoble, France.
Physiol Meas. 2017 Jun 22;38(7):1362-1372. doi: 10.1088/1361-6579/aa6737.
Respiratory monitoring is often required in experimental physiological and pharmacological studies in rodents. Currently, the mostly used techniques are direct measurement of airflow on intubated animals and whole body plethysmography.
Although the reliability of these methods has been broadly demonstrated, they also have several drawbacks such as invasiveness, high cost of use or confinement of the animals. Respiratory inductive plethysmography (RIP) is a non-invasive technique already used in medium-sized mammals that has not yet been evaluated in small rodents. The implementation of inductive plethysmography in rats represents an instrumental challenge because of the small inductances that are expected.
A rodent-specific RIP apparatus has been developed and compared to direct airflow measurement provided by a pneumotachograph (PNT) considered as the invasive gold standard for respiratory monitoring. The experiments were carried out on anesthetized rats artificially ventilated at different levels of tidal volumes (V ) covering the whole physiological range.
Based on the Euclidian distance between signals, this study shows that after calibration, signals from RIP fit at 93% with PNT values. The Bland and Altman plot evidences differences between RIP and PNT lower than 20% and the values obtained are highly correlated (R = 0.98, p < 0.001).
This study demonstrates that it is possible to design RIP systems suitable for measurement of tidal volumes and airflow in anesthetized rats. Further studies will now be focused on the validation in extended physiological conditions.
在啮齿动物的实验生理和药理研究中，通常需要进行呼吸监测。目前，最常用的技术是对插管动物的气流进行直接测量以及全身体积描记法。
尽管这些方法的可靠性已得到广泛证明，但它们也存在一些缺点，如具有侵入性、使用成本高或限制动物活动。呼吸感应体积描记法（RIP）是一种已在中型哺乳动物中使用的非侵入性技术，尚未在小型啮齿动物中进行评估。由于预期的电感较小，在大鼠中实施感应体积描记法是一项仪器方面的挑战。
已开发出一种针对啮齿动物的RIP设备，并将其与由呼吸速度描记器（PNT）提供的直接气流测量结果进行比较，PNT被视为呼吸监测的侵入性金标准。实验在不同潮气量（V）水平下人工通气的麻醉大鼠身上进行，涵盖了整个生理范围。
基于信号之间的欧几里得距离，本研究表明，校准后，RIP的信号与PNT值的拟合度为93%。布兰德-奥特曼图显示RIP和PNT之间的差异低于20%，且获得的值高度相关（R = 0.98，p < 0.001）。
本研究表明，可以设计出适用于测量麻醉大鼠潮气量和气流的RIP系统。进一步的研究现在将集中在扩展生理条件下的验证。
