OBJECTIVETo investigate the electrogastrogram (EGG) characteristics of healthy neonates.

METHODSTwenty healthy neonates born at 37-39 weeks of gestation (11 males and 9 females, Apagar's score 9.3 +/- 0.4) were enrolled in this study. EGG recordings were performed for half an hour pre- and postprandially at an interval of a week from birth until age 4 weeks. The EEG variables measured included the percentage of normal gastric rhythm, the percentage of tachygastria and bradygastria, the fed-to-fasting ratio of the EEG dominant power, as well as the EEG dominant frequency and its instability coefficient. The paired sample t test (95% CI) was used to compare the recordings.

RESULTSBetween birth and age 28 days, the percentage of normal gastric rhythm ranged from 38.2 +/- 4.9% to 39.7 +/- 3.5% of recorded time, tachygastria was observed in the range of 23.7 +/- 5.4% to 23.5 +/- 4.3% of recorded time, and bradygastria was shown to be in the range of 38.1 +/- 5.5% to 36.8 +/- 3.9% of recorded time in the 20 neonates before meal. Statistically significant differences were not seen in neonates with different ages as well as during pre- and postprandial periods. The EEG dominant frequency of neonates before meal was 2.38 +/- 0.5, 2.43 +/- 0.2, 2.54 +/- 0.3, 2.57 +/- 0.2 and 2.59 +/- 0.1 cpm at birth and at postnatal age of 7, 14, 21 and 28 days respectively. There were no significant differences in the dominant frequency and the coefficient of instability of the dominant frequency during pre- and postprandial periods. The EEG dominant frequency at postnatal age of 14, 21 and 28 days during pre- and postprandial periods was significantly higher than that at birth and at postnatal age of 7 days (P < 0.05). The coefficient of instability of the dominant frequency at postnatal age of 21 and 28 days was significantly lower than that at birth and at postnatal age of 7 and 14 days (P < 0.05). There were no statistically significant differences in the fed-to-fasting ratio of EGG dominant power in neonates with different ages.

CONCLUSIONSThe pattern of electrical activity in the normal neonatal stomach appears to be different from that demonstrated in adults and children. The percentage of normal gastric rhythm is lower, and tachygastria and bradygastria are more frequently seen. The EEG dominant frequency increases with postnatal age in neonates.