In a prospective study we investigated the influence of orogastric tube feeding on cerebral haemodynamics in 11 preterm infants (BW 1278±168 g and GA 30.5±2 wks). Data were collected at weekly intervals during the first 3 postnatal weeks. Heart rate, oxygen saturation and respiration were continuously recorded during the one hour procedure. Cerebral blood flow velocities, measured using pulsed-wave duplex-doppler, were assessed from the anterior cerebral artery 10 min before, during, and 10 and 20 min after tube feeding. For each step the doppler-data were recorded over a 2 min period. Milk was delivered via mechanical pump over a 5 min period in the first postnatal week, and a 10 min period in the 2nd and 3rd postnatal week, while the infants were placed in the prone position. The whole procedure was recorded on video for later analysis of the infants' behavioral state. To avoid the influence of tube insertion on measured parameters, milk delivery was started 2 min after the tube was inserted. Data were analyzed for all recordings (n=33) and separately for each postnatal week (n=11).

We found no significant changes in cerebral blood flow velocities in response to tube feeding at either postnatal age (Wilcoxon). The incidence of>5 sec apnea accompanied by heart rate decelerations to <100 bpm also did not significantly differ in response to feeding. For all recordings a significant increase in oxygen saturation occurred after feeding compared to prefeed values (p<0.05). This was associated with a higher incidence of quiet sleep state postprandially than before or during feeding (p<0.05).

We conclude that tube feedings do not affect the cerebral circulation in healthy preterm infants. Tube feedings do, however, influence the infants' behavioral state with apparent beneficial effects on oxygenation.