Impact of Feeding Methods on Breathing Pattern in Preterm Infants

Abstract

Background: In preterm infants, slow-infusion feeding (SF) is sometimes used to reduce apnea associated with bolus feeding (BF). It is not known if SF affects breathing pattern. The diaphragm electrical activity (EAdi) waveform allows quantification of the neural breathing pattern including respiratory effort and timing and can identify central apnea. Objective: To evaluate the effect of enteral feeding methods on neural breathing pattern in very low birth weight preterm infants. Methods: Non-ventilated preterm infants who were tolerating feeds of >=150ml/kg/d were eligible. A modified feeding tube with miniaturized sensors was inserted for continuous EAdi measurement. After 15 min of baseline (BL) measurement, infants were randomized to either BF or SF (over 90 min), followed by a crossover to the other feeding method. Five 15-min epochs were analyzed: BL, 15 and 90 min after BF (BF15, BF90) or after SF started (SF15, SF90). EAdi was analyzed for neural inspiratory and expiratory times (Nti, Nte), neural respiratory rate (Nrr), EAdi phasic (peak inspiration) and EAdi tonic (end-expiration). A flat EAdi >5 sec was defined as central apnea. Results: Ten infants with a median (range) BW of 1056 (865-1210) g and GA 27 (25-30) wks were studied. At study entry, the median (range) age was 27 (17-48) d, and weight 1480 (1041-1815) g; all were receiving caffeine and 7 were on nasal CPAP. Individual responses to the different feeding methods were variable. There were no significant differences in EAdi timing, EAdi phasic, EAdi tonic, or apnea for the different epochs. [Figure] (Table presented) Conclusion: In this pilot study of stable, non-ventilated preterm infants, neural breathing pattern does not appear to be affected by enteral feeding or the method of enteral feeds. SF does not appear to reduce the number or duration of apneas