Development of heart rate power spectra during quiet sleep reveals neonatal peculiarities of cardiorespiratory control. Patzak, Andreas, Kathrin Lipke, Wladimir Orlow, Ralf Mrowka, Harald Stauss, Elke Windt, Pontus B. Persson, and Ernst Schubert. Institute of Physiology, Institute of Medical Informatics and Biometry, Department of Neonatology, Humboldt-University of Berlin, University Hospital Charit[acute]e, 10115 Berlin, Germany
APStracts 3:0120R, 1996.
Postnatal adaptation should be associated with changes in cardiac rhythmic behavior. In order to examine the development of heart rate variability, instantaneous heart rate (IHR) and the corresponding breathing signals of 16 healthy infants were analyzed. This was pursued by using fast Fourier transformation beginning with the first day until the sixth month of life. Power in the low frequency range (LF, 0.02 to 0.2 Hz), high frequency range (HF, 0.2 to 1.5 Hz), total power (TP), the quotient LF/HF, and the frequency of the peak in LF (LFF) and HF (HFF) were derived from the IHR spectrum. The peak frequency in the high frequency range (RF) was detected in the respiratory spectrum.

Received 10 October 1995; accepted in final form 20 March 1996.
APS Manuscript Number R633-5.
Article publication pending Am. J. Physiol. (Regulatory Integrative
Comp. Physiology).
ISSN 1080-4757 Copyright 1996 The American Physiological Society.
Published in APStracts on 1 April 96