NEW YORK (Reuters Health) - 10-27-2014 Standardized slow enteral feeding (SSEF) is associated with a reduced risk of necrotizing enterocolitis (NEC) in infants born weighing less than 750 grams, compared with early enteral feeding, new findings show.
NEC remains a leading cause of mortality and morbidity in extremely preterm infants, although growing use of human breast milk to feed these babies and standardized feeding protocols have helped to reduce the disease's incidence, Dr. Sreekanth Viswanathan of Rainbow Babies and Children's Hospitals at Case Western Reserve University in Cleveland and colleagues note in their report.
Among infants born weighing less than 1,500 grams, the incidence of NEC is 7% to 9%, with a fatality rate of 15% to 30%, the team writes in the Journal of Parenteral and Enteral Nutrition, online October 14.
Some observational studies have shown an increased incidence of NEC in centers where babies are started earlier on enteral feeding and feeding volumes are advanced more rapidly, the researchers add. Dr. Viswanathan and his team hypothesized that introducing feeding more slowly to extremely low birthweight (ELBW) infants might reduce NEC risk.
To investigate, the researchers looked at 125 ELBW infants born at MetroHealth Medical Center in Cleveland who underwent the SSEF protocol, as well as 294 historic controls born at the same hospital who had received early enteral feeding. Babies were fed their mother's breast milk, when available, or formula, but donor breast milk was not used.
Under the SSEF protocol, infants born weighing less than 750 grams had 14 NPO days, followed by seven trophic feeding days; infants weighing 750 to 1,000 grams at birth had seven NPO days followed by seven trophic feeding days. While feeding advancement was 15 to 20 milliliter per kilogram per day in the historic controls, infants in the SSEF group received an additional 0.5 ml per feed every other day (less than 750 g) or every day (750-1,000 g).
Days to full feeds ranged from 16 to 22 for the historic controls, and 44 to 52 days for the babies weighing less than 750 g in the SSEF group and 32 to 36 days for the larger babies.
NEC occurred in 5.6% of the SSEF group and 11.2% of the controls (p=0.10), while 1.6% of SSEF babies and 4.8% of the controls required surgery to treat NEC (p=0.17).
When the researchers looked at babies born weighing less than 750 g, however, differences were significant. The risk of NEC was 2.1% in the smallest SSEF babies, compared to 16.2% for the smallest control infants (p<0.01). The risk of combined NEC and death was 12.8% for the SSEF group weighing less than 750 g, and 29.5% for the controls (p=0.03).
The babies in the study on the SSEF protocol who did develop NEC got sick at 60 days of age, on average, compared to 30 days for the control infants, according to Dr. Viswanathan.
Among the surviving babies, adjusted analysis showed no difference between the SSEF and control groups in discharge weight or length.
Nearly 50 babies weighing less than 750 g have been born at the study hospital over the past five years, Dr. Viswanathan noted in a telephone interview with Reuters Health, and all were treated with the SSEF protocol.
"We had only one case of NEC and that baby survived. No one died and no one required surgery for NEC," he said. "That is the group that I think benefits the most from the slow feeding protocol."
Feeding of VLBW infants varies from hospital to hospital, Dr. Viswanathan said. "There is no consensus on how to feed small babies," he added. "That's why the study is important, because in most of the centers the idea is to start early."
But any protocol is better than none, Dr. Viswanathan said. "One of the most important things if you want to reduce the NEC rate is having a standardized feeding protocol," he said. "If everyone in the unit follows the same protocol that actually itself reduces your NEC rate, but it won't eliminate NEC."
The new findings may not be generalizable to centers that use donor breast milk instead of formula, Dr. Viswanathan said. "What we believe is especially in small babies, when you switch to formula, you need to slow down so they can get adapted, and they tolerate it much better," he added.