Gastric motility in premature infants fed two different formulas

The effect of two different formulas on gastric contractions was investigated in 10 preterm infants, of mean birth weight 1,149 g and mean gestational age 30.5 weeks, who were being advanced from a 20 calorie per ounce formula (Enfamil) to a 24 calorie per ounce formula (Similac Special Care 24). The neonates were fed by gravity with a feeding tube on a 2-h schedule. The orogastric tube was connected between feedings to a pressure transducer and recorder system upon which pressure waves reflecting gastric contractions were recorded. In the 1st h after feeding there were significantly fewer gastric contractions with 24 calorie than 20 calorie formula. The mean intensity of the gastric contractions per minute of contraction time was significantly less in the 1st h after feeding with the 24 calorie compared with the 20 calorie formula. In the 2nd h after feeding these values were similar. Gastric contractions are decreased with 24 calorie formula compared with 20 calorie formula during the 1st h after feeding. This difference in contractions may influence tolerance to different formulas.