We studied the pulmonary effects of gavage bolus gastric feeds in preterm infants who had prenatal steroids and no respiratory distress syndrome or, RDS treated with surfactant. Changes in functional residual capacity (FRC), lung compliance (CL), resistance (RT), work of breathing (WOB), tidal volume (VT), frequency (F) and minute ventilation (MV) were measured in 22 neonates (BW 1369±365g, GA 30.9±2.4 wks, study age 3.9±2.9 wks, ≈ 34 wks PCA) pre and post bolus feed: 15 ml/kg by gravity dependent drainage over 20 to 30 min). Also, continuous monitoring of heart rate, pulse oximetry and temperature were done. The mean ± SD data are:Table These data indicate that even though gastric distension leads to a 20% reduction in FRC (*p<0.03), the preterm neonate is able to maintain its minute ventilation with no change in its mechanics or energetics. This reduction in FRC may explain some of the hypoxemia or desaturation associated with feeding. These data are in contrast to the deleterious effects of bolus feeding on pulmonary mechanics and ventilation previously reported by us in the pre-surfactant era. (Blondheim et al, J of Ped 1993). We still recommend that enteral feeds be cautiously and gradually administered to minimize sudden or acute changes in lung volume.
