Routes of enteral feeding

(V 1.0  05/24/00 - 04-/15/02)

The route by which a baby is fed depends upon the baby’s size, gestational age, degree of illness and support needed, and any anatomic or physiologic problems related to enteral feeding.

Most babies < 1000 - 1200g are fed COG.

Most babies requiring mechanical ventilation or NCPAP should be fed COG.

When babies are fed COG, gastric residuals are checked q3 – 4 hours.

Tolerate benign-appearing residuals of < 2cc or < 2 hours worth of feeds (whichever is more.)

Babies 1200 - 1800g and < 34 weeks are frequently fed bolus OG.

Babies who are too tachypneic to po feed or who have neurologic issues (poor suck, weak or absent gag, suck-swallow-breathe incoordination) may also be fed bolus OG.

When babies are fed bolus OG, gastric residuals are checked before each feed (q3 hours).

Tolerate benign-appearing residuals of < ½ the bolus feeding volume.

Transitioning to bolus feeds

As micropremies grow larger and more mature, convert them from continuous OG to bolus OG feeds. Perform this process slowly in a stepwise fashion and assess the baby’s tolerance.

In an ELBW infant on full COG feeds who has reached 1000 - 1200g and has weaned off assisted ventilation, begin transitioning to bolus.

1. First, add 3 hours worth of COG feeds and then divide by 2.  Write for the infant to receive that volume per hour x 2 hours and then have feeds off for 1 hour. Depending upon the baby’s weight, degree of illness, and tolerance, stay at this stage for 1 - 2 days or longer. If the baby develops feeding intolerance, resume COG feeds and try transitioning to bolus feeds when the infant is larger and more mature.

2. Write for the infant to receive the 3 hour feeding volume over 1 hour and then have feeds turned off for 2 hours. Assess as above.

3. Proceed to bolus OG feeds q3 hours.

Nasogastric feeds are very similar to orogastric feeds. Feeds may be administered by continuous infusion or bolus.

When premature babies are ill with respiratory symptoms, an orogastric tube may be preferable to an NG because babies are obligate nasal breathers. However, in more mature babies, NG tubes may be preferred because they are more easily left indwelling and may decrease vagal stimulation and gagging from passing the OG tube. NG tubes may cause fewer oral aversive tendencies than OG tubes, and are currently used in the "semi-demand" po feeding protocol for growing premies transitioning from gavage to nipple feeding.

Babies who are receiving bolus gavage feeds either NG or OG, who have reached a state of maturity and stability that enables them to suck a pacifier, should be offered the pacifier during bolus feeds for non-nutritive sucking. This practice may facilitate the development of the infant’s oromotor skills.

Infants who have severe gastroesophageal reflux (causing refractory apnea, aspiration, or growth failure) or problems with gastric emptying, may need to be fed transpylorically. TP feeds are occasionally used in an infant with gastric distension from NCPAP that is precluding COG feeding.

The bedside nurse will attempt to place the transpyloric feeding tube in the duodenum. A KUB should be obtained to verify tube position.

Transpyloric feeds must always be continuous infusions.

By bypassing the lipolytic digestive mechanisms present in the stomach, transpyloric feeds result in a 50% decrease in fat digestion and absorption. Transpyloric feeds also bypass the acidic barrier of the stomach which may potentiate pathologic bacterial colonization. Therefore, TP feeding should only be used if clinically indicated.

Babies without significant respiratory or neurologic symptoms with a gestational age of > 34 weeks may po feed.

Former premature infants being fed by gavage should be assessed for signs of po feeding readiness around 32 - 34 weeks post-conception.

Any baby who is ready to po nipple feed may learn to breast-feed.

Infants of > 32 weeks may root at the breast.

For some preterm infants who may have a poor latch-on and don’t generate much suction, breastfeeding may be more difficult for them; and they may need to be supplemented after breast feeding, or have the number of breast feeds per day limited until they are more mature and efficient feeders.

Lactation consultants are available to assist the mother-infant dyad learning breastfeeding skills.

Much of this information is also available in the 2001 NICU Manual pgs. 7-1 – 7-3.

References:

Schanler RJ, et al. Feeding strategies for premature infants: randomized trial of gastrointestinal priming and tube-feeding method. Pediatrics 1999; 103: 434-9.

De Ville K, et al. Slow infusion feedings enhance duodenal motor responses and gastric emptying in preterm infants. Am J Clin Nutr 1998; 68: 103-8.

Newell SJ. Enteral feeding of the micropremie. Clin Perinatol 2000; 27 (1): 221- 234.

Premji S, Chessell L. Continuous nasogastric milk feeding versus intermittent bolus milk feeding for premature infants less than 1500 grams. Cochrane Systematic Reviews. http://www.nichd.nih.gov/cochraneneonatal/Premji/Review.htm

Steer PA, Lucas A, Sinclair JC. "Feeding the low birthweight infant: In Sinclair JC, Bracken MB (eds): Effective Care of the Newborn Infant." Oxford University Press, 1992. pgs. 94 – 140.

Pinelli J, Symington A. Non-nutritive sucking for promoting physiologic stability and nutrition in preterm infants. Cochrane Database of Systematic Reviews. http://www.nichd.nih.gov/cochrane/Pinelli/Pinelli.HTM

Bier JB, et al. Breast-feeding of very low birth weight infants. J Pediatr 1993; 123: 773-8.