Breath hydrogen excretion in healthy premature infants.

Breath hydrogen excretion during the neonatal period was studied on 84 occasions in 44 well premature infants of 27-37 weeks gestational age who all received lactose-containing feeds. Only one of 15 infants studied during the first 24 h excreted hydrogen. Thereafter, the proportion of infants excreting hydrogen increased daily. From day 5 onwards all the infants studied were found to be excreting hydrogen. The concentration and the volume of hydrogen exhaled by infants ranged from 10-230 parts/10(6) and 2.6-107 microL/min, respectively. Breath hydrogen excretion was variable and showed no relationship to birthweight, gestation period, volume of feed or the time of last feed through there was an increase with the age of the infant. Breath hydrogen excretion appears to be a normal phenomenon in premature infants and is probably related to gut colonization with lactose fermenting organisms.