Rhythms and complexity of respiration during sleep in pre-term infants.

The aim of this study is to test rhythmic and complex properties of respiratory control in former ventilated, pre-term infants during quiet and active sleep. The children had a higher risk for sudden infant death due to bronchopulmonary dysplasia (BPD). Twelve infants suffering from BPD and 12 control infants, matched regarding their post-conceptional age, were examined polygraphically during quiet (QS) and active sleep (AS).

[Continuous blood pressure monitoring during stress ECG].

Using conventional methods (Riva-Rocci, oscillometric), non-invasive blood pressure measurements allow readings to be obtained only at discrete times, at intervals of at least one or two minutes. During exercise ECG recording, continuous blood pressure monitoring capable of detecting brief blood pressure changes is desirable. Our new approach is based on the known dependency of pulse wave velocity and blood pressure.

Linear and nonlinear properties of heart rate control in infants at risk.

The aim of this study was to test whether the heart rate (HR) control in infants at risk differs in comparison with healthy infants. Twelve former preterm infants suffering from bronchopulmonary dysplasia and 18 control infants, matched for their postconceptional age, were examined polygraphically during quiet and active sleep. HR, low-frequency (LF) power, high-frequency (HF) power, total power, and the ratio of LF to HF power (LF/HF) of the instantaneous HR spectra were calculated for linear analysis.

[Phonographic diagnostic aid in heart defects using neural networks].

New approaches to pattern recognition and modeling using neural networks also provide powerful tools for the analysis of heart sounds in the diagnosis of heart failure. This paper describes how a neutral network can be used to estimate the duration of systolic and diastolic heart phases as well as to suggest a suitable diagnosis. A neural network-based auscultation system is capable of documenting and analysing a heart sound signal by applying methods similar to those used by physicians in the subjective interpretation of stethoscopic signals.