Properties of Occlusional Devices in Extended Time–Frequency Analysis of Post-Interrupter Respiratory Signals

The usefulness of popular occlusional heads to extended, time-frequency analysis of post-interrupter respiratory data was tested in this study. A portable mobile interrupter module, designed to acquire (also in telemedical system) raw signals of mouth pressure (Q_ao) and airflow (P_ao), enabled flexible valve operation during normal breathing and flow induced by the airflow generator. The potential for algorithmic development of data processing procedures and hardware limitations of the shutter-type valve by Jaeger and Micro Medical is depicted here. The power spectrum density of P_ao and input interrupter impedance (Z_int), calculated by the Micro Medical interrupter, were sensitive indices of respiratory mechanics measurement, but problematic natural oscillations and leakage during valve closing reduced the clinical relevance of the assessments. These hardware specifications represent prerequisites for prospective research in a sensing technology domain on an optimal valve-transducer unit design.

I. Introduction

Current tendencies in physiological monitoring are oriented noninvasively, and easy measurement algorithms that are applied in cheap and reliable devices are able to be utilized in distributed telemedical systems. Such realizations combine advances in medical instrumentation (including nanotechnologies, novelties in sensor instrumentation and microprocessor-based devices), information and telecommunication technology (including wireless and mobile communication and Web-based services), medical data mining and data management systems, leading to intelligent structures (such as ambient intelligence or intelligent homes). Simultaneously, medical services take the form of personalized and patient-centered healthcare.