Factors influencing enteral feeding practices in very low birthweight and extremely low birthweight babies in New Zealand and Australian neonatal intensive care units

Abstract

Babies born very and extremely preterm have an increased risk of morbidity and mortality compared to full term babies, due to underdevelopment and complex medical complications. As these babies have not developed the suck-breath-swallow coordination required for breastfeeding, they are placed on intravenous nutrition almost from birth, and typically within 24 – 72 hours are started on enteral nutrition. Early initiation and more progressive enteral feeds are supported in research; however, the use of more conservative feeding practices are still widely prevalent. The aim of this research is to identify the factors underlying variation in practice. The FeDEra study was a secondary analysis of the ProVIDe trial, a multicentre, double-blind, randomised controlled trial of 434 extremely low-birthweight babies in New Zealand and Australia. A number of neonatal, maternal, and clinical factors were analysed to identify those which were related to enteral feeding outcomes. Enteral feeding outcomes were then analysed to observe relationships with clinical outcomes. The NoVI survey was a 29 question survey sent to currently practising neonatologists in level 3 neonatal intensive care units in New Zealand, including those sites analysed in the FeDEra study. The survey focused on understanding the beliefs underpinning enteral feeding practice for very low-birthweight babies. Significant variation in feeding outcomes was identified in the FeDEra study. For all enteral feeding measures, the NICU site was significantly associated with feeding outcome. Adjusted analysis showed site 7 took 1.1 days (95 % CI 0.2, 2.1; p= 0.008) longer than site 1, 1.1 days (95 % CI 0.2, 1.9; p= 0.004) longer than site 5 in introducing enteral feeds. Significant differences between sites for mean volume was detected in weeks 1 – 4 after birth, where the percentage of babies who achieved full enteral feeds within 14 days after birth ranged from 30 – 75% depending on NICU site. The use of fortified breastmilk feeds was also highly variable, with site 7 only using fortifier for one baby. Although 100 % of respondents in the NoVI survey identified the presence of an up-to-date written protocol for enteral feeding, the survey also identified significant variation in feeding practice across and within NICU sites. Full enteral feed volumes ranged between 150 – 180 mL.Kg-1.d-1, and only two sites showed unanimous responses. Although only two sites reported routine gastric aspirate measurement (35 %), 88 % of respondents identified that some gastric aspirate measurement would lead to a decrease or withholding of feeds. The senior medical officer was perceived to play the most important role in determining feeding decisions. Although there is evidence to support early and more progressive enteral feeds, hospital policies and practices as well as personal beliefs significantly contribute to variation in enteral feeding. The development of national consensus guidelines may mitigate some of this variation seen both across and within sites.