Spectral analysis of heart rate variability in premature infants with feeding bradycardia.
An elevated level of baseline parasympathetic activity was noted in a group of premature infants suffering from bradycardia during feeding. At approximately 34 wk post-conceptional age, the heart rates of 12 infants with feeding bradycardia (birth weight = 1539 +/- 279 g; gestational age = 31.0 +/- 1.6 wk) and 10 controls (birth weight = 1710 +/- 304 g; gestational age = 32.0 +/- 1.4 wk) were recorded 1 h before and 1 h after feeding. EKG data were digitized and 3.2-min segments of data were analyzed to determine the spectral power at very low (VLF = 0.003-0.03 Hz), low (LF = 0.03-0.39 Hz), and high (HF = 0.40-1.00 Hz) frequencies. In preterm infants with feeding bradycardia, an elevation in baseline parasympathetic activity was evident before feeding, as indicated by significantly higher HF power and a lower LF/HF ratio. This elevation in baseline parasympathetic activity may contribute to the observed bradycardia during feeding.
Veerappan
S
S
Division of Neonatology, UMDNJ-Robert Wood Johnson Medical School, St. Peter's University Hospital, New Brunswick, New Jersey 08903, USA.
Rosen
H
H
Craelius
W
W
Curcie
D
D
Hiatt
M
M
Hegyi
T
T
D001034:Apgar Score; D001724:Birth Weight / Q000502:physiology; D001835:Body Weight; D001903:Bottle Feeding / Q000009:adverse effects*; D001919:Bradycardia / Q000175:diagnosis* / Q000209:etiology*; D004562:Electrocardiography / Q000379:methods*; D005260:Female; D005865:Gestational Age; D006339:Heart Rate / Q000502:physiology; D006801:Humans; D007231:Infant, Newborn; D007234:Infant, Premature / Q000502:physiology*; D007235:Infant, Premature, Diseases / Q000175:diagnosis* / Q000209:etiology*; D008297:Male; D012815:Signal Processing, Computer-Assisted