Supporting Healthy Development in Long-Term NICU Babies
Dr Katarina Stefkova, Dr Joanfreda Etuk, Dr Cheentan Singh
The registrar explains that even though it is important to start enteral feeds as soon as possible, many infants born prematurely are given total parenteral nutrition before establishing feeds.
As well as maintaining optimal electrolyte balance, total parental nutrition contains substances like amino acids that encourage brain growth.
In the intrauterine environment, the brain undergoes crucial maturation during the third trimester. The foetal brain volume increases four-fold in size, and there is also a significant increase in brain surface area, as gyri and sulci develop in the third trimester. This is when myelination of the neurons occurs, as well as the development of dendritic spines in neurons. Neuronal organisation happens in the third trimester, and synapses form during this time too. These complex processes are all affected by preterm birth.
Factors associated with prematurity that adversely affect neurodevelopment include:
- Cystic periventricular leukomalacia
- Severe intraventricular haemorrhage
- Early bacterial sepsis
- APGAR ≤ 3 at 5 mins
Another factor affecting brain growth and development is suboptimal nutrition in the neonatal period. It has been shown that nutritional deficits in babies have adverse effects on long term neurodevelopmental outcomes. When babies are gaining weight well during their NICU stay, they are more likely to have better neurodevelopmental outcomes as toddlers.
The registrar lowers her voice, apologises to the sister and takes you to the tearoom to explain.
Premature birth exposes the babies to light, noise, tactile, chemosensory and vestibular sensory stimuli that would not have happened had the baby been born at term. All of this can affect their sensory development which could have long lasting effects.
Loud noise in the neonatal unit can have short term adverse effects on the infants, such as decreased oxygen saturations, increased heart rate or increased blood pressure. Studies have found that loud noise reduction improved long term neurocognitive outcomes in infants. It is recommended that the background noise intensity in neonatal units is below 45 dB.
NIDCAP (Newborn Individualised Developmental Care and Assessment Program) has been developed to reduce the difference between NICU environment and the expectations of the preterm human brain. NIDCAP promotes individualised care to premature infants, based on neurobehavioural observation of the babies. NIDCAP supports babies’ development, and aims to minimise the stress experienced by both infants and their families. It integrates families in the care of the infant and sees parents as important carers and nurturers.
Breastfeeding is also associated with better long term neurodevelopmental outcomes. We know that breastmilk contains specific nutrients, such as polyunsaturated fatty acids (PUFA), docosahexaenoic acid (DHA) and arachidonic acid (ARA) that help myelination and neural development. Breastmilk also protects infants against some conditions that adversely affect neurodevelopment, such as necrotising enterocolitis and sepsis.
NIDCAP has been shown reduce long-term neurodevelopmental and cognitive problems in preterm infants, and aims to maximize neurological development.
The seven neuroprotective core measures are depicted as overlapping petals of a lotus, which include
- Healing environment
- Partnering with families
- Positioning & handling
- Safeguarding sleep
- Minimizing stress and pain
- Protecting skin
- Optimizing nutrition
There have been large studies performed looking at the development of preterm babies, two of them being done in the UK and the Republic of Ireland. They looked at the survival of preterm babies as well as their impairment and developmental outcomes. EPICURE study was carried out in 1995, EPICURE 2 was performed in 2006.
The EPICURE 2 study found that 38% of infants born at 22-25 weeks gestation that survived to 48 months had some neurodevelopmental impairment. Overall, 75% of infants survived with no disability or mild impairment only.
There is a wide spectrum of neurodevelopmental issues in ex-premature babies, including cerebral palsy, learning difficulties, behavioural problems, autistic spectrum disorder and neurodiversity.
As well as affecting the developing brain, prematurity is also associated with
- Vision problems, especially due to retinopathy of prematurity (ROP)
- Impaired lung function, bronchopulmonary dysplasia
- Poor growth
- Hearing problems
- Altered glucose metabolism
TIGAR, a cohort study in England, looked at gestational age and subsequent likelihood of hospital admissions. It found that preterm babies are more likely to be admitted to hospital throughout childhood, especially due to infections.
Early intervention programmes, i.e., programmes that usually start after the infant has been discharged from the hospital, but before they reach 12 months, have been found to be beneficial for infant development. The benefits are seen during infancy and pre-school age, little is known about the effect at school age.
Some interventions focus on the motor development, such as physiotherapy sessions. Some focus on the parent-infant relationships, such as teaching the parents to read and respond to infants’ cues. These programmes may also be inclusive of speech therapy, occupational therapy, psychological services and it may be necessary to coordinate care with different specialities that can focus on the various developmental needs of the child.
EiSMART is new approach that many UK hospitals use, it is a framework that supports development in high-risk infants. This early intervention programme involves the parents as well as the multidisciplinary team. It supports infants’ sensorimotor development, attention and regulation, family relationships, as well as parental mental well-being.
A Cochrane review has found that interventions that focus on both motor development and parent-infant relationships have the greatest impact on long term cognitive development of the infants.
- The brain undergoes critical development during the third trimester of pregnancy
- Neurodevelopmental care, supporting breastfeeding and adequate nutrition have been shown to have positive effects on developing babies
- Along with neurodevelopmental issues, preterm babies are more likely to have ongoing medical conditions when growing up
Authors: Dr Katarina Stefkova, ST6 neonatal subspecialty trainee, Royal Jubilee Maternity Hospital, Belfast
Dr Joanfreda Etuk, GPST3 in Quayside Medical Practice, Derry
Consultant Supervisor: Dr Cheentan Singh, Consultant Paediatrician and Neonatologist, North Middlesex Hospital, London