Title: GASTRODUODENAL MOTILITY IN NEONATES: RESPONSE TO HUMAN MILK COMPARED TO COW-MILK FORMULA
Abstract: It is known that breast milk empties more quickly from the stomach than does cow milk formula. We studied the difference in post-prandial gastroduodenal contractions between neonates fed with human milk and those fed with formula. Twenty-four 5-36 day-old neonates were tested. Changes in luminal pressure in the gastric antrum and duodenum were recorded manometrically for 3 h. In all cases, repetitive, high amplitude non-migrating contractions were the dominant wave form during the postprandial period. The number of episodes, duration, amplitude, and frequency of non-migrating contractions were not different following the different feedings. Bursts of non-migrating contraction were 4 times more common in the duodenum (6.9±1.6 episodes/h) than in the antrum (1.8±0.9 episodes/h) (p<0.05), but an average episode lasted 3 times longer in the antrum (1.6±0.2 min vs 4.1±0.8 min, p<0.05). Non-migrating contractions had frequencies identical to those found in phase 3 of the MMC: 3-5/min in the antrum, and 11-13/min in the duodenum. The migrating myoelectric complex, which signals a return to the interdigestive (fasting) state, appeared in 15% of breast milk-fed infants, but in only 171 of formula-fed infants (p<0.05). Because contractions were similar following the two meals, but a fasting state recurred more rapidly in breast milk-fed infants, we conclude phasic, non-propagated antroduodenal contractions do not mediate differences in gastric emptying.