The sheffield respiration analysis system

The paper describes a computerised system for analysing the respiration and the instantaneous heart rate from long-term recordings of respiration and ECG. The data are analysed as they are replayed at up to 64 times the real time. The respiratory signal is obtained using thoracic wall movement sensors or impendence pneumography. The factor used to quantitate the respiration is the breath-to-breath interval, which leads directly to the identification of respiratory pauses (or apnoea). The data are analysed in nonoverlapping time epochs of 1.7 min duration (real time). The system presents the results in two forms: firstly, a `trend plot' which is a summary of the results for the 1.7 minute epochs plotted against time, and, secondly, a numerical summary which allows comparisons to be made between subjects. The system is principally designed for use in investigations into the sudden infant death syndrome (cot death), but alteration of some of the `clinical' values contained in the system may make it a suitabl tool for other research.