Overview Of Neonatal Conditions

The neonatal period is the first 28 days of life. Neonatal conditions reflect transition from fetal to extrauterine life, prematurity, congenital anomalies, perinatal events and infection. Global neonatal mortality is about 17 per 1,000 live births (2.3 million deaths yearly), with the leading causes being preterm complications, intrapartum events (birth asphyxia) and neonatal sepsis.

Gestational classification

• Preterm: under 37 weeks (extremely preterm under 28, very preterm 28 to under 32, moderate to late preterm 32 to under 37). Term: 37 to under 42 weeks. Post-term: 42 weeks or more.
• Birth weight: low (under 2500 g), very low (under 1500 g), extremely low (under 1000 g). Small for gestational age (below 10th centile), large for gestational age (above 90th centile), and fetal growth restriction.

Normal transition

First breath, clearance of lung fluid, fall in pulmonary vascular resistance, closure of ductus arteriosus (functional in the first 24 to 72 hours) and foramen ovale, thermoregulation, glucose homeostasis (nadir at 1 to 2 hours), and establishment of feeding. Physiological weight loss of 7 to 10% in the first 3 to 5 days, regained by 10 to 14 days.

Major categories of neonatal disease

• Respiratory: respiratory distress syndrome (surfactant deficiency), transient tachypnoea of the newborn, meconium aspiration syndrome, pneumonia, persistent pulmonary hypertension, pneumothorax, congenital diaphragmatic hernia, bronchopulmonary dysplasia, and apnoea of prematurity.
• Cardiac: patent ductus arteriosus, critical congenital heart disease (duct-dependent lesions), persistent pulmonary hypertension.
• Infectious: early-onset sepsis (within 72 hours: group B streptococcus, E. coli, Listeria) and late-onset sepsis, meningitis, congenital infections (TORCH), omphalitis, ophthalmia neonatorum, and tetanus.
• Neurological: hypoxic-ischaemic encephalopathy, intraventricular haemorrhage, periventricular leukomalacia, seizures, kernicterus.
• Metabolic and endocrine: hypoglycaemia, hypocalcaemia, congenital hypothyroidism, congenital adrenal hyperplasia, inborn errors of metabolism, infant of diabetic mother.
• Haematological: jaundice (physiological and pathological), haemolytic disease, anaemia, polycythaemia, thrombocytopenia, and vitamin K deficiency bleeding.
• Gastrointestinal and surgical: necrotising enterocolitis, atresias, gastroschisis, omphalocele, malrotation, Hirschsprung disease, anorectal malformation, oesophageal atresia, pyloric stenosis (later), and spontaneous intestinal perforation.
• Congenital and genetic: chromosomal anomalies, neural tube defects, hip dysplasia, clubfoot, cleft lip and palate.
• Prematurity-related: retinopathy of prematurity, bronchopulmonary dysplasia, feeding intolerance, osteopenia.
• Drug exposure: neonatal abstinence syndrome.

Assessment at birth and in the nursery

• Apgar score at 1, 5 and 10 minutes (heart rate, respiratory effort, tone, reflex irritability, colour; 7 to 10 reassuring, 4 to 6 moderate depression, 0 to 3 severe).
• Gestational age (Ballard or Dubowitz score), growth parameters plotted on centile charts.
• Vital signs: heart rate 120 to 160, respiratory rate 40 to 60 breaths/min, temperature 36.5 to 37.5 degrees Celsius, oxygen saturation 90% by 5 minutes and 95% or more by 10 minutes after birth.
• Full systematic examination within 24 hours (and again at 6 to 8 weeks).
• Red reflex, hips (Ortolani and Barlow), palate, spine, anus patency, genitalia, femoral pulses, and neurological tone and primitive reflexes (Moro, rooting, grasp).

Common presentations needing recognition

• Respiratory distress: tachypnoea above 60, grunting, nasal flaring, retractions, cyanosis.
• Cyanosis: central cyanosis (cardiac or respiratory), acrocyanosis (normal in first 24 to 48 hours).
• Jaundice: within 24 hours is pathological (haemolysis); physiological peaks at 3 to 5 days in term infants.
• Poor feeding, lethargy, temperature instability, apnoea: non-specific signs of sepsis, hypoglycaemia, metabolic disease or cardiac disease.
• Seizures: subtle, clonic, tonic or myoclonic.
• Bilious vomiting: intestinal obstruction (malrotation with volvulus is a surgical emergency).
• Failure to pass meconium within 48 hours: Hirschsprung disease, meconium ileus (cystic fibrosis), anorectal malformation.
• Abdominal distension, bloody stools: necrotising enterocolitis.
• Hypotonia, floppy infant: sepsis, hypoxic-ischaemic injury, genetic disorders, neuromuscular disease.
• Dysmorphism and congenital malformations.
• Red flags: grunting with cyanosis, shock, bilious vomiting, apnoea, seizures, weak pulses (coarctation, left heart obstruction), hypoglycaemia, jaundice in the first 24 hours, and maternal infection or prolonged membrane rupture.

Antenatal and perinatal risk assessment (maternal diabetes, infection, hypertension, drugs, fetal anomalies on scans, GBS status, rupture of membranes, delivery mode, meconium staining) guides evaluation.

Core investigations by problem

• Sepsis screen: blood culture (before antibiotics, at least 1 mL), CBC with differential (immature to total neutrophil ratio above 0.2), CRP (serial at 24 and 48 hours), lumbar puncture when sepsis is likely or symptomatic, urine culture for late-onset, and chest radiograph.
• Respiratory: chest radiograph (ground-glass, air bronchograms in RDS), blood gas, pulse oximetry screening for critical congenital heart disease (preductal and postductal saturations, positive if below 90% or difference over 3%, or 90 to 94% on repeat), and echocardiography.
• Hypoglycaemia: bedside glucose (below 2.6 mmol/L or 47 mg/dL requires action), and critical sample (insulin, cortisol, growth hormone, ketones, lactate, free fatty acids) if persistent.
• Jaundice: transcutaneous or serum bilirubin plotted on gestation-specific nomogram (Bhutani curve or NICE thresholds), blood group, Coombs test, haemoglobin, reticulocytes, G6PD.
• Metabolic screening: newborn blood spot at 48 to 72 hours (phenylketonuria, congenital hypothyroidism, sickle cell disease, cystic fibrosis, MCAD deficiency, congenital adrenal hyperplasia, other inborn errors), ammonia, lactate and blood gas if suspected metabolic disease.
• Hearing screen (otoacoustic emissions or automated auditory brainstem response) before discharge.
• Imaging: cranial ultrasound for preterm infants at day 3 to 7 and weeks 4 to 6 (intraventricular haemorrhage graded I to IV, periventricular leukomalacia).
• Other imaging: abdominal radiograph and contrast studies for obstruction, renal ultrasound, hip ultrasound at 6 weeks for risk factors, and MRI brain for encephalopathy.
• Genetic tests: karyotype, microarray and gene panels for dysmorphism or anomalies.

Delivery room and resuscitation

• Delayed cord clamping for at least 30 to 60 seconds in vigorous infants. Dry, warm and stimulate.
• If not breathing or heart rate below 100: position airway, positive pressure ventilation with air (21% oxygen at term, 21 to 30% in preterm titrated to oximetry).
• Chest compressions 3:1 if heart rate below 60 after 30 seconds of effective ventilation.
• Adrenaline 0.01 to 0.03 mg/kg IV (0.1 mL/kg of 1:10,000) for persistent bradycardia, volume expansion 10 mL/kg isotonic saline.
• Therapeutic hypothermia for moderate-severe encephalopathy.
• Skin-to-skin contact and early breastfeeding for stable infants. Plastic bag or wrap for infants under 32 weeks to prevent hypothermia.

Routine newborn care

• Vitamin K: phytomenadione 1 mg IM (0.5 mg if under 1.5 kg) at birth to prevent haemorrhagic disease.
• Hepatitis B vaccine and BCG per schedule, eye prophylaxis where recommended, umbilical cord care (dry cord care, chlorhexidine 4% in high-mortality settings), exclusive breastfeeding, thermal care.
• Monitor for jaundice, feeding, weight, and early discharge criteria.
• Prevention of hypoglycaemia: early feeding.
• Treat hypoglycaemia with buccal glucose gel 200 mg/kg (0.5 mL/kg of 40% gel) with feeding. For persistent hypoglycaemia give IV dextrose 10% 2 mL/kg then infusion 5 to 8 mg/kg/min.

Respiratory support

• Antenatal corticosteroids (betamethasone 12 mg IM, two doses 24 hours apart) at 24 to 34 weeks with threatened preterm delivery reduce RDS, IVH and mortality. Antenatal magnesium sulfate for neuroprotection below 32 weeks.
• Early CPAP (5 to 8 cmH2O), less invasive surfactant administration (poractant alfa 200 mg/kg, 100 mg/kg repeat, or beractant) for RDS.
• Caffeine citrate 20 mg/kg load then 5 to 10 mg/kg daily for apnoea of prematurity and to facilitate extubation.
• Lung-protective ventilation, and minimal oxygen targets (saturation 90-94% for preterm, to reduce retinopathy of prematurity).
• Persistent pulmonary hypertension: oxygen, ventilation optimisation, inhaled nitric oxide 20 ppm, sildenafil 0.5 to 2 mg/kg every 6 to 8 hours, milrinone, and ECMO.

Infection

• Early-onset sepsis: ampicillin 50 mg/kg IV every 12 hours (every 8 hours after 7 days, or higher doses for meningitis) plus gentamicin 4 to 5 mg/kg IV every 24 hours (term; extended intervals in preterm), with levels, for 7 to 10 days (14 to 21 days for meningitis).
• Cefotaxime 50 mg/kg every 8 to 12 hours is an alternative to gentamicin in meningitis.
• Intrapartum antibiotic prophylaxis (penicillin G or ampicillin) for GBS carriers. Stop antibiotics at 36 to 48 hours if cultures are negative and the infant is well.
• Late-onset sepsis: flucloxacillin (or vancomycin 15 mg/kg every 8 to 12 hours) plus gentamicin or cefotaxime, tailored to cultures.

Jaundice

Phototherapy (blue light 460 to 490 nm, irradiance 30 microwatts/cm2/nm) according to gestation- and age-specific thresholds. Stop phototherapy and check rebound bilirubin.

Exchange transfusion for bilirubin approaching threshold or acute bilirubin encephalopathy (double-volume 160 mL/kg). Give IVIG 0.5 to 1 g/kg for isoimmune haemolysis, and hydration.

Neurological

Therapeutic hypothermia (33.5 degrees Celsius for 72 hours) within 6 hours of birth for moderate-severe hypoxic-ischaemic encephalopathy at 36 weeks or more. Seizures: phenobarbital 20 mg/kg IV load (then 5 mg/kg daily), second-line levetiracetam 40-60 mg/kg or phenytoin, midazolam. EEG monitoring.

Nutrition and growth

• Breast milk (with fortifier for preterm), parenteral nutrition for very low birth weight infants, trophic feeds and slow advancement, probiotics (selected), donor milk where mother's milk unavailable, and vitamin D 400 units daily. Iron supplementation 2 mg/kg/day from 2 to 6 weeks in preterm infants.
• Surgical emergencies: early referral for bilious vomiting, abdominal wall defects (cover with sterile plastic wrap, nasogastric decompression, fluids), diaphragmatic hernia (intubation, avoid bag-mask ventilation), oesophageal atresia, and necrotising enterocolitis (stop feeds, antibiotics, decompression).

Follow-up and developmental care

Neurodevelopmental follow-up for infants born under 32 weeks or with encephalopathy (at 2 years corrected age). Retinopathy of prematurity screening (infants under 32 weeks or under 1500 g at 4 to 6 weeks postnatal age), hearing screening, growth monitoring, and immunisation at chronological age.

Give RSV prophylaxis (nirsevimab 50 mg if under 5 kg, 100 mg if over 5 kg, single dose before the first season) in eligible infants, and support parents. Kangaroo mother care reduces mortality in low-birth-weight infants.