A Preterm Infant’s Ability to Make the Transition

The ability of a preterm infant to make the transition from gavage to oral nipple feeding depends on the infant’s neurodevelopment in relation to behavioral organization, to a rhythmic suck-swallow-breathe pattern, and to cardiorespiratory regulation. Research-based knowledge about infant neurodevelopment in these three areas has led to the creation of a semidemand feeding method to aid in this transition. The method combines the use of nonnutritive sucking to promote awake behavior for feeding, use of behavioral assessment to identify readiness for feeding, and systematic observation of and response to infant behavior cues to regulate frequency, length, and volume of oral feedings. Semidemand feeding may be individualized for healthy preterm infants. This article discusses both the relevant knowledge about neurodevelopment and the semidemand feeding method itself. Accepted for publication October 2002. This research was funded by NIH grant # NINR, NIH R01 NR04083 to the author. infant expresses the full range of behavioral states, from quiet sleep to crying; wakes easily; keeps eyes open; and maintains an alert state.3–5 This milestone is important for oral feeding because it is related to the infant’s ability to sustain organized, awake behavior. From 32 weeks PCA to term age, maturation of the brain structure is associated with improvement in behavioral state expression and motor organization.6,7 As the infant matures, awake state and quiet sleep behavior increase, and active sleep behavior decreases.2,4,8 Although an infant of 32 weeks PCA is able to express a full range of behaviors, that expression is less robust and more prone to disorganization than that of a term infant. The caregiver therefore has more difficulty detecting signs of hunger and feeding readiness. Whereas the term infant gives clear hunger signals, such as crying loudly and sucking on fists, the preterm infant demonstrates less arousal and fewer direct signals of hunger, such as sucking on fingers or on a pacifier.9,10 In the prefeeding context, nonnutritive sucking on a pacifier not only indicates hunger, but also brings preterm infants to a quiet awake state.11 This quiet awake behavior is the optimal state for successful oral feeding.9,12 That the preterm infant (<35 weeks PCA) does not cry loudly to signal his caregiver when hungry is one reason nursery staff tend to feed these infants on schedules. As a result, they are fed according to clock time and not in response to feeding readiness behaviors. For example, a caregiver may try to feed an infant who is asleep because the scheduled clock time serves as the signal to initiate the feeding. The result of trying to feed a sleeping infant is that he will not suck and swallow, and the feeding is judged as unsuccessful. Alternatively, the sleepy infant tries to feed, but is not awake enough to coordinate sucking and swallowing, and choking is the result. Evidence indicates that preterm infants are ready to self-regulate feeding at 32 to 35 weeks PCA.1,13,14 Self-regulatory feeding is when an infant is fed based on awake or restless behavior cues, with oral feedings progressing and concluding according to the infant’s ability to tolerate them without fatigue or distress. Because infants (32–35 weeks PCA) fed in response to self-regulatory behaviors have demonstrated an increase in quiet sleep time13 and a decrease in the amount of time required to feed orally, these feedings have been judged successful. In addition, preterm infants (>32 weeks PCA) fed ad lib volumes have had adequate weight gains comparable to infants fed prescribed volumes.1,14,15 A benefit of this selfregulatory approach is that the infant could have more opportunities to practice nipple feeding because all feedings are initiated based on infant cues. Three studies have reported that increasing the number of feeding opportunities hastens the attainment of oral feeding in preterm infants.1,14,16 Evidence indicates that preterm infants are ready for demand feeding at >35 weeks PCA.17 4 6 S E P T E M B E R / O C TO B E R 2 0 0 3 , V O L . 2 2 , N O . 5 N E O N A T A L N E T W O R K FIGURE 1 ■ Gavage/oral feeding guideline for healthy preterm infants. NNS = nonnutritive sucking. If sleeping If If awake, restless If Every 3 hours offer NNS for 5–10 minutes and follow with an assessment of infant behavioral state Permit to sleep 1/2 hour more Offer NNS for 5–10 minutes followed by a behavioral assessment