Gestational maturation of electrical activity of the stomach

Gestational maturation of gastrointestinal motility is a key factor in read iness of the preterm neonates for enteral nutrition. Since gastric motility mainly depends on the electrical activity of the smooth muscle cells, it w as of interest to investigate the developmental aspects of electrical activ ity of the stomach. The latter was recorded weekly through cutaneous electr ogastrography in 27 preterm infants (aged 29-34 weeks of gestation). Record ings were done for 1 hr before and 1 hr after meal. The electrogastrographi c variables measured were: percentage of normal gastric rhythm, ie, 2-4 cpm ; percentage of tachygastria (>4 cpm); the fed-to-fasting ratio of the domi nant electrogastrographic power; and the instability coefficient of the dom inant frequency. Data were compared with those measured in 10 full-term inf ants. Peaks of normal electrical activity (2-4 cpm) were present in most of the recordings at all the gestational ages; however, percentages of both n ormal electrical rhythm and tachygastria in preterm infants were similar to those measured in full-term infants (mean +/- so) (normal rhythm; fasting: 70.2 +/- 3.8, fed: 72.2 +/- 5.0; tachygastria: fasting: 24.6 +/- 4.0, fed: 19.1 +/- 3.5) by 35 weeks of gestation (normal rhythm, fasting: 67.5 +/- 2 .0, fed: 69.6 +/- 4.4; tachygastria: fasting: 27.1 +/- 4.0, fed: 25.6 +/- 4 .1), The coefficient of instability of the dominant frequency in preterm in fants was also similar to the value measured in full-term infants by 35 wee ks of gestation, whereas the EGG power showed a significant increase in the postprandial state at all the gestational ages. We conclude that a maturat ion pattern of the electrical activity of the stomach can be detected by me ans of a noninvasive tool such as cutaneous electrogastrography: a normal e lectrical rhythm can be detected at very early gestational ages; however, t his activity becomes dominant at around the 35 weeks of gestational age. In preterm infants developmental changes of gastric electrical activity are a function of advancing postnatal age.