Comparison of two devices for assessment of the interrupter resistance in preschool children

Respiratory interrupter resistance (Rint) proved to be a useful lung function index in preschool children. In this brief report, we show the results obtained comparing two Rint devices: MicroRint (MicroMedical) and Pony (Cosmed). This comparison is very relevant in clinical practice because MicroRint, which was mostly used in the literature, is no longer available on the market, while no Rint reference values were reported using Pony. Briefly, 81 children [median age (range) 4.6 (2.8-6.0) yr] undertook Rint measurements with both devices, in a random order. We also evaluated the short-term repeatability of Pony in a different set of 25 children [median age (range) 4.8 (3.2-5.7) yr]. The mean (SD) of the difference Pony-MicroRint was small, albeit significant [0.046 (0.12) kPa.l-1.s, p = 0.001]. The limits of agreement between the two devices were 0.286 to -0.194 kPa.l-1.s. The short-term repeatability of Pony was 0.26 kPa.l-1.s, very similar to the one
previously published for MicroRint. In conclusion, we suggest that, in preschool children, normative data previously collected with MicroRint can be applied to measurements made with Pony, at least for clinical purposes, with acceptable error. However, these findings need to be confirmed in children with a greater range of ages and resistance values.

The device that was mostly used in the literature to calculate Rint reference values and repeatabilty is no longer available on the market. A formal comparison of that device with a similar device is expected to have a great impact on clinical practice.

Received: Sept 10, 2022
Accepted: Oct 2, 2022
Published: Nov 1, 2022


Table of Contents: Vol. 1, n. 0, November 2022

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