Immediate Management of the Tiny Baby (< 1,000g)

Summary
Introduction
Antenatal corticosteroids
Resuscitation
Nursery management
Areas of Uncertainty in Clinical Practice

Summary

the most experienced staff should care for tiny babies
avoidance of hypothermia/cold stress is paramount
transepidermal water loss should be minimised
volutrauma (secondary to excessive tidal volume) and hyperoxaemia should be avoided
extreme care should be taken with skin attachments

Introduction

Although in excess of 90% of babies less than 1,000 grams or < 28 weeks gestation are delivered in tertiary centres, occasionally, a tiny baby is delivered in a level 2 (or smaller) hospital. Although it is mandatory to transfer these babies ex utero by NETS to a level 3 NICU, there is ordinarily some delay between delivery and the arrival of the transport team. The following is a guide to the management of the tiny baby pending arrival of NETS.

Wherever possible, the most experienced doctors and nurses available should care for these babies. This is particularly important with respect to any procedures.

It is also important to contact NETS or level 3 personnel early.

Antenatal corticosteroids

Although the effectiveness on fetal lung maturity of steroids administered to the mother less than 24 hours prior is unclear, there are other benefits, for example the prevention of intraventricular haemorrhage. Therefore, even if delivery is thought to be inevitable, treatment with antenatal steroids should always be considered.

Resuscitation

refer to section on resuscitation for general principles
avoidance of hypothermia/cold stress is paramount; heat loss can be minimised by the following
- infants less than 28 weeks gestation should be placed immediately after birth in a polyethylene bag or wrap and the body completely covered (appropriate size, food grade, heat resistant)
- a less satisfactory alternative is to take the following steps
  - avoid evaporative heat loss — dry the infant
  - avoid conductive heat loss — ensure that wraps are/remain warm (i.e. replace if necessary)
  - reduce radiant heat loss — manage baby under a radiant heater
  - avoid convective heat loss — avoid drafts, keep baby away from air conditioning ducts
  - N.B. ‘blanketing’ is ineffective in tiny babies as they are unable to generate enough heat to warm the air between the skin and the blanket; bubble wrap between the baby and the overhead heater is preferable as it allows transmission of heat and reduces convective heat loss
it is extremely likely that the baby will require endotracheal intubation
- refer to the section on endotracheal intubation
- use a 2.5 mm endotracheal tube
- oral intubation is recommended if
  - the infant is < 26 weeks’ gestation
  - the tube cannot be easily passed through the nose
  - the doctor is inexperienced/is having difficulty with nasotracheal intubation

an oral tube should be tied at 6.5 to 7.0 cm at the lips

a nasal tube should be tied at 7.5 to 8.0 cm at the nares

alternatively, if using a Portex tube, the tube should be inserted until the black marker ‘disappears’ beyond the vocal cords

an End tidal C0₂ detector should be used to confirm correct tube position

it may be helpful to check for symmetrical breath sounds

once intubated, most tiny babies respond rapidly to IPPV (or bag and mask ventilation if endotracheal intubation is not possible)
- IPPV may be provided with
  - a ‘Neopuff’
  - a Laerdal bag
  - an anaesthetic bag attached to a manometer (experienced hands only)
- aim for a PEEP of 5 cm H₂0
- use enough PIP to ensure adequate, but not excessive chest wall movement
- aim to replicate the baby’s endogenous respiratory rate (~ 60 pbm)
- where ever possible the infant should be placed onto a mechanical ventilator (the ‘Neopuff’ is an alternative)

the baby should receive 0.5 mg Vitamin K intramuscularly

Nursery management

procedures should be undertaken under a radiant heater. Once completed, ideally, the baby should be placed in a double walled humidified isolette. However, if this is not available, the baby should remain under a radiant heater (servo controlled, if possible). The baby should be covered directly with bubble wrap or indirectly with cling wrap, preferably in a humidified (60-80%) environment — see section on thermoregulation
if the baby is placed on a mechanical ventilator, the following settings are recommended
- inspiratory time — 0.35 seconds
- expiratory time — 0.65 seconds
- respiratory rate — 60 breaths per minute
- PEEP — 5 cm H₂0
- PIP — that required to ensure adequate, but not excessive chest movement
the following monitoring guidelines are recommended
- FiO₂ — this should be altered to maintain percutaneous SaO₂ between 90-95% with alarms set at 88-96% (high saturations may increase the risk of retinopathy of prematurity)
- transcutaneous electrodes should be used with caution (e.g. heated to 43 not 44 degrees) as they can strip the immature epidermis
- the skin is extremely fragile and liable to break down —the following products help to avoid this trauma but if they are not available remember that it is better to use all available monitoring equipment and standard probe attachments in order to avoid excessive handling of the infant
  - hydrogel products should be used for all electrodes and temperature probe placement
  - hydrocolloid products (e.g Comfeel Coloplast) should be applied under all taping
  - an elastic non adhesive tape (Coban) should be used to secure pulse oximeter probes and peripheral cannulas
a chest x-ray should be organised to ensure correct position of the endotracheal tube and assess the type/severity of lung disease
venous access should be obtained
- umbilical venous catheter < 26 weeks (this can also be used for sampling)
- intravenous cannula (25 gauge) in bigger babies
fluids should be commenced at 80 mls/kg/day of 10% dextrose
the baby should not be fed
if possible, the following blood tests should be performed (to facilitate discussion with NETS)
- blood sugar level
- blood gas
- blood culture
because of the high risk of perinatal sepsis, even if a blood culture cannot be taken, intravenous antibiotics should be given (even though many babies may not eventually prove to be septic or have a ‘set up’ for perinatal sepsis)
- penicillin 60mg/kg
- gentamicin 2.5 mg/kg
following discussion with NETS, particularly if the retrieval is to be delayed, and in experienced hands, the baby may be given exogenous surfactant

if there are concerns about poor perfusion, then volume expansion in the form of 10 mL/kg 0.9% normal saline should be considered

the baby may require inotropic support, although this should follow discussion with NETS

blood pressure should be measured every 30 minutes

Areas of Uncertainty in Clinical Practice

the role of limiting tidal volume rather than just pressure in the resuscitation of the tiny infant

References

Crowley P. Prophylactic corticosteroids for preterm birth. The Cochrane Library 2001 Issue 2

Donoghue D, Cust A. Report of the Australian & New Zealand Neonatal Network: 1999. University of Sydney

Harpin V, Rutter N. Humidity of incubators. Arch Dis Child 1985;60:219-224

Flenady VJ, Woodgate PG. Radiant warmers versus incubators for regulating body temperature in newborn infants. The Cochrane Library 2001 Issue 2

Bucher H, Fanconi S, Baeckert P, Duc G. Hyperoxaemia in newborn infants: detection by pulse oximetry. Paediatrics 1989;84:226-30

Sorm K, Jenson T. Skin care of preterm infants: strategies to minimise potential damage. Journal of Neonatal Nursing 1999;5:13-5