Patterns of gastric myoelectrical activity in human subjects with different ages. Chen, J. D. Z., E. Co, J. Liang, J. Pan, J. Sutphen, R. B. Torres -Pinedo, and W. C. Orr. Lynn Institute for Healthcare Research, INTEGRIS Baptist Medical Center, Oklahoma City, Oklahoma, University of Virginia Health Science Center, Charlottesville, Virginia
APStracts 3:0256G, 1996.
The aim of this study was to investigate the developmental change of gastric myoelectrical activity in humans. Five groups of healthy subjects were studied, including ten pre-term newborns, eight full -term newborns, eight full-term infants at the age of 2-6 months, nine children at the age of 4-11 years, and nine adults. Gastric myoelectrical activity was recorded using surface electrogastrography for 30 minutes before and 30 minutes after a test meal in each subject. Spectral analysis methods were applied to compute the parameters of the electrogastrogram (EGG), including the dominant frequency and power of the EGG and the percentage of the normal gastric slow waves in each recording period. The results showed that: 1) there was an absence of normal gastric slow waves in both pre-term and full-term newborns at birth. The percentage of the 2-4 cycles per minute (cpm) slow waves was 26.6 +/- 3.9% in pre-term newborns and 30.0 +/- 4.0% in the full-term newborns. 2) in comparison with the newborns, the infant group of 2-6 months showed a significantly higher percentage of normal gastric slow waves. The 2-4 cpm slow wave was 70.0 +/- 6.1%, and the dominant frequency was 3.1 +/- 0.08 cpm. 3) the EGG in the children group showed a higher percentage of regular gastric slow waves than in the infant and newborn groups. The percentage of the 2-4 cpm slow wave was 84.6 +/- 3.2% in the fasting state, which was not changed by the test meal. The dominant frequency was 2.9 +/- 0.08 cpm in the fasting state and increased to 3.16 +/- 0.05 cpm in the fed state (p<0.03). A significant increase in the power of the EGG at 3 cpm was observed after the test meal (33.5 +/- 1.6 dB v 38.1 +/- 1.4 dB, p<0.01). 4) the characteristics of the EGG obtained in the adult group were similar to those in the children group. The percentage of the 2-4 cpm slow wave was 88.9 +/- 2.2% in the fasting state which was not changed by the test meal. The dominant frequency of the EGG was 2.85 +/- 0.06 cpm in the fasting state and increased to 3.09 +/- 0.09 cpm after the test meal (p<0.02). About 3 dB increase in the power of the EGG at 3 cpm was observed after the test meal (p=0.06). In conclusion, gastric slow waves are absent at birth, and there is a maturing process after birth. Age-matched controls are necessary for the interpretation of EGG data from neonates and infants, whereas the EGG in children is the same as in adults.

Received 17 April 1996; accepted in final form 15 November 1996.
APS Manuscript Number G137-6.
Article publication pending Am. J. Physiol. (Gastrointest. Liver
Physiology).
ISSN 1080-4757 Copyright 1996 The American Physiological Society.
Published in APStracts on 31 December 1996