The premature newborn infant Ola Didrik Saugstad

The premature newborn infant

• Ola Didrik Saugstad

• Department of Pediatric Research

• Rikshospitalet University Hospital

• University of Oslo, Norway

• Student lecture 9th semester

Prematurity

• GA < 259 days (37 weeks)

• Norway: 5.6% (1988) and 6.5% (1996)

• < 1.5 kg 0.7-1.0% (528 = 0.9% in 1996)

• < 1.0 kg 0.3 % (200 =0.3% in 1996)

• USA: 7% among caucasians 18% among black

Preterm infants

• Slight 32-36 weeks

• Feeding and temperature problems, some have immature lungs

• Moderate 28-31 weeks

• Immature lungs, temperature control, feeding problems, apneas

• Severe < 28 weeks

• Immature organ systems, intensive care

Terminology

• Low birth weight < 2.5 kg

• Very Low Birth Weight < 1.5 kg

• Extremely Low birth Weight < 1.0 kg

• Premature < 37 weeks

• Immature < 28 weeks

• ELGAN: Extremely Low Gestational Age Newborn < 26 weeks

• Small for gestational age < 2.5 percentile

General problems in premature infants

• Feeding: (IV – Gavage)

• Temperature control: (incubator-heated bed)

• Respiratory control: apneas, Respiratory support CPAP, Artificial ventilation

• Immature lungs – lack of surfactant: Oxygen suppl, Respiratory support (CPAP, ventilator)

• Immature brain: brain hemorrhage and cysts

• Immunology: risk of infections (antibiotics)

• Organ injury (Brain, Eye, Lung, Intestine, Skin

• Long term consequences

Survival

• 1940: 50% with BW1500 gram survive

• 2000: 50% with BW 600 gram survive

• Birth weight % Survival after 1 year

• 350-499 g 14

• 500-799 g 47

• 750-999 g 76_______________

• Medical Birth Registry 1992-96

Survival

• Gestational age weeks Survival %

• 21 0-4

• 22 0-12

• 23 8-36

• 24 12-62

• 25 31-79

• 26 53-85

• NFR’s Consensus report 1999

Sequels

• From 1979 to 1994 survival among preterm infatns with BW 501-800 gr increased from 20 to 59%.

• The percentage of children with severe neurosensory injury was however, unchanged

• (O’Shea 1997)

Injury of ELGANs 1972-1990

• < 26 uker < 800 gram

• Mental retardation 14% 14%

• Cerebral palsy 12% 8%

• Blindness 8% 8%

• Deafness 3% 3%

• ”Major disability” 22% 24%

• Survival increased, however rate of injury was constant

Injury of preterm infants

• Eye ( Retinopathy of prematurity ROP

• Stage 1-5)

• Brain injury (Intracranial hemorrhage (grade 1-4) Periventricular leukomalacia PVL). Immature capillaries (plexus Choroides), hemodynamic changes, intrauterine inflammation

• Pulmonary ( Bronchopulmonary dysplasia - BPD, Chronic lung disease - CLD)

• Intestinal (necrotizing enterecolitis - NEC)

School problems

• A Dutch study showed that > 50% with BW < 1500 gram needed extra support at school

• No relation between Gestational age and injury

• Preterm infants have to be followed-up at least till school age because these problems have a late debut. Learning problems picked up around 8 years

• ADHD

• Hyperactivity

• Intellectual problems (arithmetics, solving problems, cognitive functions)

• Short term memory

• Coordination problems

• Behavioral problems (shy, sport performance, sosialise )

• Boys> girs

• Low Socioeconomic conditions

Future challenges

• Prevent preterm birth

• Understand relation between intrauterine conditions and postnatal injury

• Improved nutrition

• Improved technology

• New drugs (antioxidants, anti inflammatory, etc)

• New insight into the needs and the psychological development