Total urine masses (mean ± SD) over 4 h were smaller than the still-water control (1337 ± 330 g) after an oral rehydration solution (ORS) (1038 ± 333 g, P < ), full-fat milk (1052 ± 267 g, P < ), and skimmed milk (1049 ± 334 g, P < ). Cumulative urine output at 4 h after ingestion of cola, diet cola, hot tea, iced tea, coffee, lager, orange juice, sparkling water, and a sports drink were not different from the response to water ingestion. The mean BHI at 2 h was ± for the ORS, ± for full-fat milk, and ± for skimmed milk.
Of 963 infants who were assigned to caffeine and who remained alive at a postmenstrual age of 36 weeks, 350 (36 percent) received supplemental oxygen, as did 447 of the 954 infants (47 percent) assigned to placebo (adjusted odds ratio, ; 95 percent confidence interval, to ; P<). Positive airway pressure was discontinued one week earlier in the infants assigned to caffeine (median postmenstrual age, weeks; interquartile range, to ) than in the infants in the placebo group (median postmenstrual age, weeks; interquartile range, to ; P<). Caffeine reduced weight gain temporarily. The mean difference in weight gain between the group receiving caffeine and the group receiving placebo was greatest after two weeks (mean difference, -23 g; 95 percent confidence interval, -32 to -13; P<). The rates of death, ultrasonographic signs of brain injury, and necrotizing enterocolitis did not differ significantly between the two groups.