[Reproducibility of inspiratory mouth occlusion pressure with a mobile computer-assisted measuring system]

The measurement of mouth occlusion pressure is an easy method to assess respiratory drive and muscle function. In addition to a variety of stationary systems, recently a mobile computer assisted system became available. In this study the repeatability of inspiratory mouth occlusion pressures with such a mobile system was examined.

Maximal inspiratory mouth occlusion pressure (PImax), mouth occlusion pressure 100 ms after onset of normal inspiration (P0,1), and PImax after 100 ms (P0,1max) were investigated 4 times in 12 healthy subjects. Measurements were performed with a mobile system (resPImax). Criteria of repeatability were analysis of variance, intraindividual standard deviation, variation coefficient and intraclass correlation coefficient.

Of all analyzed parameters PImax was most reproducible with a 5.3% share of variance due to measurement methods of the total variance. P0,1 was least reproducible. There was no statistically significant difference between the results of each day. The variance due to measurement methods varied between 5.3% and 30%.

The repeatability of mouth occlusion pressures with this mobile device was good and partly superior to stationary systems. The concept of a mobile measuring unit simplifies getting results of bed-bound and mechanically ventilated patients.