The normal neonate

Definition and introduction

A neonate is an infant aged from birth to 28 days of life. This is a period of rapid change and vulnerability for both the infant and their parents. Neonates are at higher risk than older infants of serious bacterial infections and may also present with previously unsuspected congenital abnormalities. Many parents have limited family support and little experience to guide them through this time. Stress and anxiety can be at a peak during the middle of the night when the emergency department (ED) is often the only service available. It is important for emergency clinicians to be familiar with the wide range of normal neonatal appearance, behaviour and development to avoid unnecessary and unhelpful over-investigation and treatment. Familiarity is best gained through the experience of evaluating large numbers of young infants while maintaining an open and curious attitude to learning; a challenge at 2:00 a.m.!

Immediately after birth

Babies are sometimes born unexpectedly in the ED or the immediate vicinity (such as the back seat of the car, in the ambulance bay or car park). A midwife or paediatrician may not be immediately available, and the ED staff will be responsible for the initial management of both mother and child.

Birth at term is usually an uncomplicated process producing a healthy infant; however, up to 1% of infants do require some type of resuscitation at birth. Preterm delivery is associated with higher risks and the need for a different approach and specialist assistance.

Emergency clinicians should be familiar with newborn resuscitation (see Chapter 4.5 , Neonatal resuscitation) and attend skills training with regular refreshers to maintain competence. It is unlikely that emergency staff will be required to perform newborn resuscitation sufficiently often to maintain skills without focused training sessions.

A newborn with good tone (flexed limbs, moving) and who responds to gentle stimulation (drying with a soft warm towel) by breathing/crying does not need resuscitation. Most newborn babies simply require drying and stimulating with a warm towel before being placed on the mother’s chest for skin-to-skin contact. Babies are blue immediately after birth and can take several minutes to pink up. They do not require bag/mask ventilation or oxygen, provided that they have a satisfactory heart rate (>100 beats per min) and establish regular breathing after their initial gasps. Excessive oxygenation may be harmful to newborn infants. Guidance on normal oximetry measurements and other details are available in Australian and New Zealand Committee on Resuscitation newborn resuscitation guidelines ( https://www.resus.org.nz/healthcare-resources/guidelines/?id=9 ).

There is no rush to divide the umbilical cord unless there are urgent reasons to move and resuscitate mother or baby. It is likely that delaying cord clamping for at least 60 seconds increases haemoglobin concentrations and iron stores in infants.

Newborn babies are at risk of haemorrhagic disease of the newborn, due to vitamin K deficiency. Neonates should receive a single dose of 1 mg of intramuscular vitamin K shortly after birth to reduce the risk of bleeding.

Newborn babies are vulnerable to heat loss. Mother and baby should be looked after in a warm area and shielded from radiant, conductive, evaporative and convective heat loss.

The neonatal history

A neonatal history should include a strong focus on maternal health, history of the pregnancy and delivery, and antenatal screening. A number of maternal problems during pregnancy can place the infant at risk such as diabetes, infections, certain medications or illicit drug use. Prolonged rupture of membranes (>18 hours) prior to delivery places the infant at greater risk of sepsis from organisms such as group B streptococcus. Postnatal depression is common and can present with feeding difficulties, poor weight gain and general anxiety about the baby’s health. Birth weight should always be recorded and compared with current weight. All infants lose weight after birth, commonly up to 10% of birth weight. Most infants regain their birth weight by 10 to 12 days of age. Feeding can be a source of difficulty even in infants who are otherwise well, and this is a key sign of illness and illness severity. Jaundice is frequent and usually normal or physiological (see Chapter 4.4 , Acute neonatal emergencies). Physiological jaundice appears during the first 1 to 2 days after birth and usually peaks on days 4 to 5. It may persist for several weeks, especially in breast-fed infants. Physiological jaundice is unconjugated, with a conjugated component of <10% of the total. Jaundice which is unusually prolonged or continuing to increase after the first week of life should be evaluated to rule out biliary atresia and other liver disease. It is important to diagnose biliary atresia early, before 6 weeks of age, to achieve good treatment outcomes. Fever (>38°C), on history or examination, is not always present in neonatal sepsis. Serious infection can present with poor feeding, sleepiness, pallor, hypotonia and normal or low temperature. When present, fever is an important sign which should trigger investigations for significant infections.