Soft tissue injuries

These include:

Nerve palsies

Brachial nerve palsy results from traction to the brachial plexus nerve roots. They may occur at breech deliveries or with shoulder dystocia. Upper nerve root (C5 and C6) injury results in an Erb palsy (Fig. 10.7). It may be accompanied by phrenic nerve palsy causing an elevated diaphragm. Most palsies resolve completely, but should be referred to an orthopaedic or plastic surgeon if not resolved by 2–3 months. Most recover by 2 years. A facial nerve palsy may result from compression of the facial nerve against the mother’s ischial spine. It is unilateral, and there is facial weakness on crying but the eye remains open. It is usually transient, but methylcellulose drops may be needed for the eye. Rarely, nerve palsies may be from damage to the cervical spine, when there is lack of movement below the level of the lesion.

Birth injuries

Soft tissue injuries

• Caput succedaneum, cephalhaematoma, chignon, bruises and abrasions

• Subaponeurotic haemorrhage

Nerve palsies

• Brachial plexus – Erb palsy

• Facial nerve palsy

Fractures

• Clavicle, humerus, femur

Fractures

Respiratory distress syndrome

In respiratory distress syndrome (RDS), (also called hyaline membrane disease), there is a deficiency of surfactant, which lowers surface tension. Surfactant is a mixture of phospholipids and proteins excreted by the type II pneumocytes of the alveolar epithelium. Surfactant deficiency leads to widespread alveolar collapse and inadequate gas exchange. The more preterm the infant, the higher the incidence of RDS; it is common in infants born before 28 weeks’ gestation and tends to be more severe in boys than girls. Surfactant deficiency is rare at term but may occur in infants of diabetic mothers. The term hyaline membrane disease derives from a proteinaceous exudate seen in the airways on histology. Glucocorticoids, given antenatally to the mother, stimulate fetal surfactant production and are given if preterm delivery is anticipated (see Ch. 9.)

The development of surfactant therapy has been a major advance. The preparations are natural, derived from extracts of calf or pig lung. They are instilled directly into the lung via a tracheal tube. Multinational placebo-controlled trials show that surfactant treatment reduces mortality from RDS by about 40%, without increasing the morbidity rate (Fig. 10.11).

At delivery or within 4 h of birth, babies with RDS develop clinical signs of:

The characteristic chest X-ray appearance is shown in Figure 10.12. Treatment with raised ambient oxygen is required, which may need to be supplemented with continuous positive airway pressure (delivered via nasal cannulae) or artificial ventilation via a tracheal tube. The ventilatory requirements need to be adjusted according to the infant’s oxygenation (which is measured continuously), chest wall movements and blood gas analyses. Mechanical ventilation (with intermittent positive pressure ventilation or high-frequency oscillation) may be required. High-flow humidified oxygen therapy, via nasal cannulae, may be used to wean babies from added oxygen therapy.

The preterm infant: maturational changes in appearance and development

Table 10.1

The preterm infant compared with the term infant

Gestation	23–27 weeks	Term (37–42 weeks)
Birthweight (50th centile)	At 24 weeks – male 700 g, female 620 g	At 40 weeks – male 3.55 kg, female 3.4 kg
Skin	Very thin (Fig. 10.9a)	Thick skin (Fig. 10.9b)
	Dark red colour all over body	Pale pink colour
Ears	Pinna soft, no recoil	Pinna firm, cartilage to edge, immediate recoil
Breast tissue	No breast tissue palpable	One or both nodules >1 cm
Genitalia	Male – scrotum smooth, no testes in scrotum	Male – scrotum has rugae, testes in scrotum
	Female – prominent clitoris, labia majora widely separated, labia minora protruding	Female – labia minora and clitoris covered
Breathing	Needs respiratory support. Apnoea common	Rarely needs respiratory support. Apnoea rare
Sucking and swallowing	No coordinated sucking	Coordinated (from 34–35 weeks)
Feeding	Usually needs TPN (total parenteral nutrition), then tube feeding	Cries when hungry. Feeds on demand
Cry	Faint	Loud
Vision, interaction	Eyelids may be fused. Infrequent eye movements. Not available for interaction	Makes eye contact, alert wakefulness
Hearing	Startles to loud noise	Responds to sound
Posture	Limbs extended, jerky movements	Flexed posture, smooth movements

Respiratory distress syndrome

• Common in very preterm infants

• Caused by surfactant deficiency

• Antenatal corticosteroids and surfactant therapy markedly reduce morbidity and mortality.

Pneumothorax

In respiratory distress syndrome, air from the overdistended alveoli may track into the interstitium, resulting in pulmonary interstitial emphysema (PIE). In up to 10% of infants ventilated for RDS, air leaks into the pleural cavity and causes a pneumothorax (Fig. 10.13). When this occurs, the infant’s oxygen requirement usually increases, and the breath sounds and chest movement on the affected side are reduced, although this can be difficult to detect clinically. A pneumothorax may be demonstrated by transillumination with a bright fibreoptic light source applied to the chest wall. A tension pneumothorax is treated by inserting a chest drain. In order to try and prevent pneumothoraces, infants are ventilated with the lowest pressures that provide adequate chest movement and satisfactory blood gases.

Apnoea and bradycardia and desaturation

Episodes of apnoea and bradycardia and desaturation are common in very low birthweight infants until they reach about 32 weeks’ gestational age. Bradycardia may occur either when an infant stops breathing for over 20–30 s or when breathing continues but against a closed glottis. An underlying cause (hypoxia, infection, anaemia, electrolyte disturbance, hypoglycaemia, seizures, heart failure or aspiration due to gastro-oesophageal reflux) needs to be excluded, but in many instances, the cause is immaturity of central respiratory control. Breathing will usually start again after gentle physical stimulation. Treatment with the respiratory stimulant caffeine often helps. Continuous positive airways pressure (CPAP) may be necessary if apnoeic episodes are frequent.

Temperature control

Hypothermia causes increased energy consumption and may result in hypoxia and hypoglycaemia, failure to gain weight and increased mortality. Preterm infants are particularly vulnerable to hypothermia, as:

There is a neutral temperature range in which an infant’s energy consumption is at a minimum level. In the very immature baby, this neutral temperature is highest during the first few days of life and subsequently declines. The temperature of these small babies is maintained using incubators (Fig. 10.14) or initially with overhead radiant heaters. Incubators also allow ambient humidity to be provided, which reduces transepidermal heat loss.

Temperature control

Prevention of heat loss in newborn infants

1 Convection

• Raise temperature of ambient air in incubator

• Clothe, including covering head

• Avoid draughts

2 Radiation

• Cover baby

• Double walls for incubators

3 Evaporation

• Dry and wrap at birth; if extremely preterm place baby’s body directly into plastic bag at birth

• Humidify incubator

4 Conduction

• Nurse on heated mattress.

Patent ductus arteriosus

The ductus arteriosus remains patent in many preterm infants. Shunting of blood across the ductus, from the left to the right side of the circulation, is most common in infants with RDS. It may produce no symptoms or it may cause apnoea and bradycardia, increased oxygen requirement and difficulty in weaning the infant from artificial ventilation. The pulses are ‘bounding’ from an increased pulse pressure, the precordial impulse becomes prominent and a systolic murmur may be audible. With increasing circulatory overload, signs of heart failure may develop. More accurate assessment of the infant’s circulation can be obtained on echocardiography. If the infant is symptomatic, pharmacological closure with a prostaglandin synthetase inhibitor, indometacin or ibuprofen, is used. If these measures fail to close a symptomatic duct, surgical ligation will be required.

Fluid balance

A preterm infant’s fluid requirements will vary with gestational and chronological age. On the first day of life, about 60–90 ml/kg is usually required. This is adjusted according to the infant’s clinical condition, plasma electrolytes, urine output and weight change. Subsequent fluid volume is increased by 20–30 ml/kg per day to 150–180 ml/kg per day.

Nutrition

Preterm infants have a high nutritional requirement because of their rapid growth. Preterm infants at 28 weeks’ gestation double their birthweight in 6 weeks and treble it in 12 weeks, whereas term babies double their weight in only 4.5 months and treble it in a year.

Infants of 35–36 weeks’ gestational age are mature enough to suck and swallow milk. Less mature infants will need to be fed via an oro- or nasogastric tube. Even in very preterm infants, enteral feeds, preferably breast milk, are introduced as soon as possible. In these infants, breast milk needs to be supplemented with phosphate and may need supplementation with protein and calories (in breast milk fortifier) and calcium. In some neonatal units, extremely preterm infants are initially fed on donor breast milk if maternal breast milk is not available. If formula feeding is required, special infant formulas are available which are designed to meet the increased nutritional requirements of preterm infants but, in contrast to breast milk, do not provide protection against infection or other benefits of breast milk. In the very immature or sick infant, parenteral nutrition is often required. This is usually given through a central venous catheter, inserted peripherally (PICC lines, peripherally inserted central catheters), paying strict attention to aseptic technique both during insertion and when fluids are changed. However, PICC lines carry a significant risk of septicaemia; other risks include thrombosis of a major vein. For this reason, parenteral nutrition may sometimes be given via a peripheral vein, but extravasation may cause skin damage with scarring. Because of the significant risk of septicaemia from parenteral nutrition and the increased risk of necrotising enterocolitis with cow’s milk based formula, mothers should be encouraged and supported to provide breast milk.

Poor bone mineralisation (osteopenia of prematurity) was previously common but is prevented by provision of adequate phosphate, calcium and vitamin D. Because iron is mostly transferred to the fetus during the last trimester, preterm babies have low iron stores and are at a risk of iron deficiency. This is in addition to loss of blood from sampling and an inadequate erythropoietin response. Iron supplements are started at several weeks of age and continued after discharge home.

Infection

Preterm infants are at increased risk of infection, as IgG is mostly transferred across the placenta in the last trimester and no IgA or IgM is transferred. In addition, infection in or around the cervix is often a reason for preterm labour and may cause infection shortly after birth. Most infections in preterm infants occur after several days of age and are nosocomial (hospital-derived); they are often associated with indwelling catheters or artificial ventilation. Infection is considered in more detail later in this chapter.

Preterm brain injury

Haemorrhages in the brain occur in 25% of very low birthweight infants and are easily recognised on cranial ultrasound scans (Fig. 10.15a). Typically, they occur in the germinal matrix above the caudate nucleus, which contains a fragile network of blood vessels. Most haemorrhages occur within the first 72 h of life. They are more common following perinatal asphyxia and in infants with severe respiratory distress syndrome. Pneumothorax is a significant risk factor. Small haemorrhages confined to the germinal matrix do not increase the risk of cerebral palsy. Haemorrhage may occur in the ventricles. The most severe haemorrhage is unilateral haemorrhagic infarction involving the parenchyma of the brain; this usually results in hemiplegia (Fig. 10.15b).

A large intraventricular haemorrhage may impair the drainage and reabsorption of cerebrospinal fluid (CSF), thus allowing CSF to build up under pressure. This dilatation (Fig. 10.15c) may resolve spontaneously or progress to hydrocephalus, which may cause the cranial sutures to separate, the head circumference to increase rapidly and the anterior fontanelle to become tense. A ventriculoperitoneal shunt may be required, but initially symptomatic relief may be provided by removal of CSF by lumbar puncture or ventricular tap. About half of infants with progressive post-haemorrhagic ventricular dilatation have cerebral palsy, a higher proportion if parenchymal infarction is also present.

Periventricular white matter brain injury may occur following ischaemia or inflammation and may occur in the absence of haemorrhage. It is more difficult to detect by cranial ultrasound. Initially there may be an echodense area or ‘flare’ within the brain parenchyma. This may resolve within a week (in which case the risk of cerebral palsy is not increased), but if cystic lesions become visible on ultrasound 2–4 weeks later, there is definite loss of white matter. Bilateral multiple cysts, called periventricular leukomalacia (PVL), have an 80–90% risk of spastic diplegia, often with cognitive impairment, if posteriorly sited (Fig. 10.15d).

Both intraventricular haemorrhage and periventricular leukomalacia may occur in the absence of abnormal clinical signs.

Necrotising enterocolitis

Necrotising enterocolitis is a serious illness mainly affecting preterm infants in the first few weeks of life. It is associated with bacterial invasion of ischaemic bowel wall. Preterm infants fed cow’s milk formula are more likely to develop this condition than if they are fed only breast milk. The infant stops tolerating feeds, milk is aspirated from the stomach and there may be vomiting, which may be bile-stained. The abdomen becomes distended (Fig. 10.16a) and the stool sometimes contains fresh blood. The infant may rapidly become shocked and require artificial ventilation because of abdominal distension and pain. The characteristic X-ray features are distended loops of bowel and thickening of the bowel wall with intramural gas, and there may be gas in the portal tract (Fig. 10.16b). The disease may progress to bowel perforation, which can be detected by X-ray or by transillumination of the abdomen.

Treatment is to stop oral feeding and give broad-spectrum antibiotics to cover both aerobic and anaerobic organisms. Parenteral nutrition is always needed and artificial ventilation and circulatory support are often needed. Surgery is performed for bowel perforation. The disease has significant morbidity and a mortality of about 20%. Long-term sequelae include the development of strictures and malabsorption if extensive bowel resection has been necessary.

Cranial ultrasound in preterm infants

Retinopathy of prematurity

Retinopathy of prematurity (ROP) affects developing blood vessels at the junction of the vascular and non-vascularised retina. There is vascular proliferation which may progress to retinal detachment, fibrosis and blindness. It was initially recognised that the risk is increased by uncontrolled use of high concentrations of oxygen. Now, even with careful monitoring of the infant’s oxygenation, retinopathy of prematurity is still found in about 35% of all very low birthweight infants. As laser therapy reduces visual impairment, the eyes of susceptible preterm infants (<1500 g birthweight or <32 weeks’ gestation) are screened every week by an ophthalmologist. Severe bilateral visual impairment occurs in about 1% of very low birthweight infants, mostly in infants of <28 weeks’ gestation.

Bronchopulmonary dysplasia

Infants who still have an oxygen requirement at a post-menstrual age of 36 weeks are described as having bronchopulmonary dysplasia (BPD) or chronic lung disease. The lung damage comes from pressure and volume trauma from artificial ventilation, oxygen toxicity and infection. The chest X-ray characteristically shows widespread areas of opacification, sometimes with cystic changes (Fig. 10.17). Some infants need prolonged artificial ventilation, but most are weaned onto continuous positive airways pressure (CPAP) followed by additional ambient oxygen, sometimes over several months. Corticosteroid therapy may facilitate earlier weaning from the ventilator and often reduces the infant’s oxygen requirements in the short term, but concern about increased risk of abnormal neurodevelopment including cerebral palsy limits use to those at highest risk and only short courses are given. Some babies go home while still receiving additional oxygen. A few infants with severe disease may die of intercurrent infection or pulmonary hypertension. Subsequent pertussis and RSV (respiratory syncytial virus) infection may cause respiratory failure necessitating intensive care.

Necrotising enterocolitis

Problems following discharge

To prevent anaemia of prematurity, additional iron as supplementation or in preterm formula is given until 6 months corrected age, when iron becomes available from solid foods. Multivitamins are also recommended. The standard immunisations should be given.

Medical problems include increased risk of:

Readmission to hospital during the first year of life is increased approximately four-fold – mainly for respiratory disorders and surgical repair of inguinal hernias.

About 5–10% of very low birthweight infants develop cerebral palsy, but the most common impairments are learning difficulties. The prevalence of cognitive impairment and of other associated difficulties increases with decreasing gestational age at birth, and is greatest if born at very early gestational age (<26 weeks’ gestation) (Fig. 10.18a,b). It becomes increasingly evident when the individual child is compared to their peers at nursery or school. In addition, children may have difficulties with:

(b) Proportion of survivors with disability at 11 years of age. (Adapted from Johnson S et al. 2009. Neurodevelopmental disability through 11 years of age in children born before 26 weeks of gestation. Pediatrics 124:e249–e257). Preterm babies born in 2006 show a 30% increase in numbers born at <26 weeks and increased survival. Long-term follow-up is in progress.

A small proportion also have hearing impairment, with 1–2% requiring amplification, or visual impairment, with 1% blind in both eyes. A greater proportion have refraction errors and squints and therefore require glasses.

Summary

Clinical evaluation

Babies become clinically jaundiced when the bilirubin level reaches about 80 µmol/L. Management varies according to the infant’s gestational age, age at onset, bilirubin level and rate of rise, and the overall clinical condition.

Management

Poor milk intake and dehydration will exacerbate jaundice and should be corrected, but studies have failed to show that routinely supplementing breast-fed infants with water or dextrose solution reduces jaundice. Phototherapy is the most widely used therapy, with exchange transfusion for severe cases.

Jaundice at >2 weeks of age

Jaundice in babies more than 2 weeks old (3 weeks if preterm), is called persistent or prolonged neonatal jaundice. The key feature is that it may be caused by biliary atresia, and it is important to diagnose biliary atresia promptly, as delay in surgical treatment adversely affects outcome (see Ch. 20 for further details).

However, in most infants with persistent neonatal jaundice, the hyperbilirubinaemia is unconjugated, but this needs to be confirmed on laboratory testing.

In prolonged unconjugated hyperbilirubinaemia:

• ‘Breast milk jaundice’ is the most common cause, affecting up to 15% of healthy breast-fed infants; the jaundice gradually fades and disappears by 4–5 weeks of age.

• Infection, particularly of the urinary tract, needs to be considered.

• Congenital hypothyroidism may cause prolonged jaundice before the clinical features of coarse facies, dry skin, hypotonia and constipation become evident. Affected infants should be identified on routine neonatal biochemical screening (Guthrie test).

Conjugated hyperbilirubinaemia (>25 µmol/L) is suggested by the baby passing dark urine and unpigmented pale stools. Hepatomegaly and poor weight gain are other clinical signs that may be present. Its causes include neonatal hepatitis syndrome and biliary atresia, with improved prognosis of biliary atresia with early diagnosis (see Ch. 20 for further details).

Summary

Transient tachypnoea of the newborn

This is by far the commonest cause of respiratory distress in term infants. It is caused by delay in the resorption of lung liquid and is more common after birth by Caesarean section. The chest X-ray may show fluid in the horizontal fissure. Additional ambient oxygen may be required. The condition usually settles within the first day of life but can take several days to resolve completely. This is a diagnosis made after consideration and exclusion of other causes.

Meconium aspiration

Meconium is passed before birth by 8–20% of babies. It is rarely passed by preterm infants, and occurs increasingly the greater the gestational age, affecting 20–25% of deliveries by 42 weeks. It may be passed in response to fetal hypoxia. At birth these infants may inhale thick meconium. Asphyxiated infants may start gasping and aspirate meconium before delivery. Meconium is a lung irritant and results in both mechanical obstruction and a chemical pneumonitis, as well as predisposing to infection. In meconium aspiration the lungs are over-inflated, accompanied by patches of collapse and consolidation. There is a high incidence of air leak, leading to pneumothorax and pneumomediastinum. Artificial ventilation is often required. Infants with meconium aspiration may develop persistent pulmonary hypertension of the newborn which may make it difficult to achieve adequate oxygenation despite high pressure ventilation (see below for management). Severe meconium aspiration is associated with significant morbidity and mortality.

Pneumonia

Prolonged rupture of the membranes, chorioamnionitis and low birthweight predispose to pneumonia. Infants with respiratory distress will usually require investigation to identify any infection. Broad-spectrum antibiotics are started early until the results of the infection screen are available.

Pneumothorax

A pneumothorax may occur spontaneously in up to 2% of deliveries. It is usually asymptomatic but may cause respiratory distress. Pneumothoraces also occur secondary to meconium aspiration, respiratory distress syndrome or as a complication of ventilation. (Management is described earlier in this chapter.)

Milk aspiration

This occurs more frequently in preterm infants and those with respiratory distress or neurological damage. Babies with bronchopulmonary dysplasia often have gastro-oesophageal reflux, which predisposes to aspiration. Infants with a cleft palate are prone to aspirate respiratory secretions or milk.

Persistent pulmonary hypertension of the newborn

This life-threatening condition is usually associated with birth asphyxia, meconium aspiration, septicaemia or respiratory distress syndrome. It sometimes occurs as a primary disorder. As a result of the high pulmonary vascular resistance, there is right-to-left shunting within the lungs and at atrial and ductal levels. Cyanosis occurs soon after birth. Heart murmurs and signs of heart failure are often absent. A chest X-ray shows that the heart is of normal size and there may be pulmonary oligaemia. An urgent echocardiogram is required to establish that the child does not have congenital heart disease.

Most infants require mechanical ventilation and circulatory support in order to achieve adequate oxygenation. Inhaled nitric oxide, a potent vasodilator, is often beneficial. Another vasodilator, sildenafil (Viagra), has been introduced more recently. High-frequency or oscillatory ventilation is sometimes helpful. Extracorporeal membrane oxygenation (ECMO), where the infant is placed on heart and lung bypass for several days, is indicated for severe but reversible cases, but is only performed in a few specialist centres.

Diaphragmatic hernia

This occurs in about 1 in 4000 births. Many are now diagnosed on antenatal ultrasound screening. In the newborn period, it usually presents with failure to respond to resuscitation or as respiratory distress. In most cases, there is a left-sided herniation of abdominal contents through the posterolateral foramen of the diaphragm. The apex beat and heart sounds will then be displaced to the right side of the chest, with poor air entry in the left chest. Vigorous resuscitation may cause a pneumothorax in the normal lung, thereby aggravating the situation. The diagnosis is confirmed by X-ray of the chest and abdomen (Fig. 10.21). Once the diagnosis is suspected, a large nasogastric tube is passed and suction is applied to prevent distension of the intrathoracic bowel. After stabilisation, the diaphragmatic hernia is repaired surgically, but in most infants with this condition the main problem is pulmonary hypoplasia – where compression by the herniated viscera throughout pregnancy has prevented development of the lung in the fetus. If the lungs are hypoplastic, mortality is high.

Other causes

Other causes of respiratory distress are listed in Table 10.3. When due to heart failure, abnormal heart sounds and/or heart murmurs may be present on auscultation. An enlarged liver from venous congestion is a helpful sign. The femoral arteries must be palpated in all infants with respiratory distress, as coarctation of the aorta and interrupted aortic arch are important causes of heart failure in newborn infants.

Early-onset infection

In early-onset sepsis (<48 h after birth), bacteria have ascended from the birth canal and invaded the amniotic fluid. The fetus is secondarily infected because the fetal lungs are in direct contact with infected amniotic fluid. These infants have pneumonia and secondary bacteraemia/septicaemia. In contrast, congenital viral infections and early-onset infection with Listeria monocytogenes, fetal infection is acquired via the placenta following maternal infection.

The risk of early-onset infection is increased if there has been prolonged or premature rupture of the amniotic membranes, and when chorioamnionitis is clinically evident such as when the mother has fever during labour. Presentation is with respiratory distress, apnoea and temperature instability (Box 10.2). A chest X-ray is performed, together with a septic screen. A full blood count is performed to detect neutropenia, as well as blood cultures. An acute-phase reactant (C-reactive protein) is helpful but takes 12–24 h to rise, so one normal result does not exclude infection, but two consecutive normal values are strong evidence against infection. Antibiotics are started immediately without waiting for culture results. Intravenous antibiotics are given to cover group B streptococci, Listeria monocytogenes and other Gram-positive organisms (usually benzylpenicillin or amoxicillin), combined with cover for Gram-negative organisms (usually an aminoglycoside such as gentamicin). If cultures and CRP are negative and the infant has recovered clinically, antibiotics can be stopped after 48 h. If the blood culture is positive or if there are any neurological signs, CSF must be examined and cultured.

Late-onset infection

In late-onset infection (>48 h after birth), the source of infection is often the infant’s environment. The presentation is usually non-specific (Box 10.2). Nosocomially acquired infections are an inherent risk in a neonatal unit, and all staff must adhere strictly to effective hand hygiene measures to prevent cross-infection. In neonatal intensive care, the main sources of infection are indwelling central venous catheters for parenteral nutrition, invasive procedures which break the protective barrier of the skin, and tracheal tubes. Coagulase-negative staphylococcus (Staphylococcus epidermidis) is the most common pathogen, but the range of organisms is broad, and includes Gram-positive bacteria (Staphylococcus aureus and Enterococcus faecalis) and Gram-negative bacteria (Escherichia coli and Pseudomonas, Klebsiella and Serratia species). Initial therapy (e.g. with flucloxacillin and gentamicin) is aimed to cover most staphylococci and Gram-negative bacilli. If the organism is resistant to these antibiotics or the infant’s condition does not improve, specific antibiotics (e.g. vancomycin for coagulase-negative staphylococci or enterococci) or broad-spectrum antibiotics (e.g. meropenem) may be indicated. Use of prolonged or broad-spectrum antibiotics predisposes to invasive fungal infections (e.g. Candida albicans) in premature babies. Serial measurements of an acute-phase reactant (CRP) are useful to monitor response to therapy.

Neonatal meningitis, although uncommon, has a mortality of 20–50%, with one-third of survivors having serious sequelae. Presentation is non-specific (Box 10.2); a bulging fontanelle and hyperextension of neck and back (opisthotonos) are late signs and rarely seen in newborn infants. If meningitis is thought likely, ampicillin or penicillin and a third-generation cephalosporin (e.g. cefotaxime, which has CSF penetration) are given. Complications include cerebral abscess, ventriculitis, hydrocephalus, hearing loss and neurodevelopmental impairment.

Around 10–30% of pregnant women have faecal or vaginal carriage of group B streptococci. The organism causes early- and late-onset sepsis. In early-onset sepsis, the newborn baby has respiratory distress and pneumonia. In the UK, approximately 0.5–1 in 1000 babies have early-onset infection; most have pneumonia only, but it may cause septicaemia and meningitis. The severity of the neonatal presentation depends on the duration of the infection in utero. Mortality in babies with positive blood or CSF cultures is up to 10%.

Up to half of infants born to mothers who carry group B streptococcus are colonised on their mucous membranes or skin. Some of these babies develop late-onset disease, up to 3 months of age. It usually presents with meningitis, or occasionally with focal infection (e.g. osteomyelitis or septic arthritis).

In colonised mothers, risk factors for infection are preterm, prolonged rupture of membranes, maternal fever during labour (>38° C), maternal chorioamnionitis or previously infected infant. Prophylactic intrapartum antibiotics given intravenously to the mother can prevent group B streptococcus infection in the newborn baby. There are two approaches to the use of intrapartum antibiotics – universal screening at 35–38 weeks to identify mothers who carry the organism (as practiced in the USA and Australia) and a risk-based approach, in which mothers with risk factors for infection are offered antibiotics (as in the UK).

Conjunctivitis

Sticky eyes are common in the neonatal period, starting on the 3rd or 4th day of life. Cleaning with saline or water is all that is required and the condition resolves spontaneously. A more troublesome discharge with redness of the eye may be due to staphylococcal or streptococcal infection and can be treated with a topical antibiotic eye ointment, e.g. neomycin.

Purulent discharge with conjunctival injection and swelling of the eyelids within the first 48 h of life may be due to gonococcal infection. The discharge should be Gram-stained urgently, as well as cultured, and treatment started immediately, as permanent loss of vision can occur. In countries such as the UK and the USA where penicillin resistance is a problem, a third-generation cephalosporin is given intravenously. The eye needs to be cleansed frequently.

Chlamydia trachomatis eye infection usually presents with a purulent discharge, together with swelling of the eyelids (Fig. 10.22), at 1–2 weeks of age, but may also present shortly after birth. The organism can be identified with immunofluorescent staining. Treatment is with oral erythromycin for 2 weeks. The mother and partner also need to be checked and treated.

Pierre Robin sequence

The Pierre Robin sequence is an association of micrognathia (Fig. 10.25), posterior displacement of the tongue (glossoptosis) and midline cleft of the soft palate. There may be difficulty feeding and, as the tongue falls back, there is obstruction to the upper airways which may result in cyanotic episodes. The infant is at risk of failure to thrive during the first few months. If there is upper airways obstruction, the infant may need to lie prone, allowing the tongue and small mandible to fall forward. Persistent obstruction can be treated using a nasopharyngeal airway. Eventually the mandible grows and these problems resolve. The cleft palate can then be repaired.

Small bowel obstruction

This may be recognised antenatally on ultrasound scanning. Otherwise, small bowel obstruction presents with persistent vomiting, which is bile-stained unless the obstruction is above the ampulla of Vater. Meconium may initially be passed, but subsequently its passage is usually delayed or absent. Abdominal distension becomes increasingly prominent the more distal the bowel obstruction. High lesions will present soon after birth, but lower obstruction may not present for some days.

Small bowel obstruction may be caused by:

• Atresia or stenosis of the duodenum (Fig. 10.27) – one-third have Down syndrome and it is also associated with other congenital malformations

• Atresia or stenosis of the jejunum or ileum – there may be multiple atretic segments of bowel

• Malrotation with volvulus – a dangerous condition as it may lead to infarction of the entire midgut

• Meconium ileus – thick inspissated meconium, of putty-like consistency, becomes impacted in the lower ileum; almost all affected neonates have cystic fibrosis

• Meconium plug – a plug of inspissated meconium causes lower intestinal obstruction.

The diagnosis is made on clinical features and abdominal X-ray showing intestinal obstruction. Atresia or stenosis of the bowel and malrotation are treated surgically, after correction of fluid and electrolyte depletion. A meconium plug will usually pass spontaneously. Meconium ileus may be dislodged using Gastrografin contrast medium.

Large bowel obstruction

This may be caused by:

Exomphalos/gastroschisis

These lesions are often diagnosed antenatally (see Ch. 9). In exomphalos (also called omphalocele), the abdominal contents protrude through the umbilical ring, covered with a transparent sac formed by the amniotic membrane and peritoneum (Fig. 10.28). It is often associated with other major congenital abnormalities. In gastroschisis, the bowel protrudes through a defect in the anterior abdominal wall, adjacent to the umbilicus, and there is no covering sac (see Fig. 9.2). It is not associated with other congenital abnormalities.

Gastroschisis carries a much greater risk of dehydration and protein loss, so the abdomen of affected infants should be wrapped in several layers of clingfilm to minimise fluid and heat loss. A nasogastric tube is passed and aspirated frequently and an intravenous infusion of dextrose established. Colloid support is often required to replace protein loss. Many lesions can be repaired by primary closure of the abdomen. With large lesions, the intestine is enclosed in a silastic sac sutured to the edges of the abdominal wall and the contents gradually returned into the peritoneal cavity.