- 1.1 Neonatal Thrombocytopenia
- 1.2 Neonatal Sepsis
- 1.3 Prolonged Hyperbilirubinemia
- 1.4 Hypoglycemia in Newborn
- 1.5 Respiratory Distress Syndrome in Preterm
- 1.6 Neonatal Shock
- 1.7 Apnea of Prematurity
- 1.8 Newborn Screening
1.1 NEONATAL THROMBOCYTOPENIA
DEFINITION
The “normal range” of platelets differ with gestation, but working definition of low platelets is 1.5 × 106/L.
ETIOLOGY
- Sick baby
- Sepsis—especially gram-negative
- Necrotizing enterocolitis (NEC)
- Perinatal asphyxia
- Therapeutic hypothermia/severe hypothermia
- Intrauterine infections—cytomegalovirus (CMV)
- Fungal infections
- Nonsick baby
- Severe intrauterine growth restriction (IUGR)
- Neonatal alloimmune thrombocytopenia (NAIT)
- Maternal immune thrombocytopenia purpura (ITP)
- Rare conditions: Large hemangioma with thrombocytopenia.
EPIDEMIOLOGY
- Early onset (<72 hours): If clinical signs of bleeding are present—consider NAIT and CMV infections
- Early onset (<72 hours): If no clinical signs of bleeding—consider maternal pregnancy-induced hypertension (PIH), maternal ITP
- Late onset: Infections are most likely.
SIGNS AND SYMPTOMS
- Skin bleeds in form of petechiae, puncture site bleeds
- Bleed from mucosa: Endotracheal, gastric bleeds
- Serious manifestations: Intracranial bleed
- Serious manifestations: Bleeding and shock.
TREATMENT AND COURSE
- Look for general condition and stabilize airway and breathing in a sick bleeding neonate
- Look for shock and correct
- Look for severe pallor and consider packed red blood cell transfusions.
The thresholds for platelet transfusions vary, but safe working guidelines are given in Table 1.1.1.
- Platelets are stored at 22°C and should not be refrigerated
- Platelets are stored on an agitator in blood bank, they cannot be transfused long after they are issued
- There are not significant differences in single donor platelets and apheresis in most clinical situations.
DIFFERENTIAL DIAGNOSIS
Bleeding can be due to coagulation factor defects and other local factors.
DIAGNOSIS
- Automated complete blood count
- Confirmation of platelet clumping and morphology on peripheral blood film by pathologist
- Antibody studies when NAIT is suspected
- Neurosonogram/abdominal scan: Severe pallor/shock.
PROGNOSIS AND PREVENTION
- Most babies with low platelets do not have severe bleeding
- NAIT can result in severe fatal bleeding
- In extreme preterm babies, intraventricular hemorrhage (IVH) and pulmonary hemorrhage can be fatal/associated with long-term morbidities.
1.2 NEONATAL SEPSIS
ETIOLOGY
The risk factors for early onset and late onset sepsis differ (Table 1.2.1). The predominant organism for neonatal sepsis, irrespective of timing of infection is Klebsiella pneumoniae in India. Other gram-negative rods (Escherichia coli, Pseudomonas spp, Acinetobacter spp) and Staphylococcus aureus are also major contributors.
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EPIDEMIOLOGY
- An estimated one million newborns die from infections in developing countries
- World Health Organization (WHO) estimates suggest that sepsis, pneumonia, tetanus and diarrhea cause 32% of neonatal deaths with high case fatality rates of 45%.
SIGNS AND SYMPTOMS
- No single diagnostic sign or symptom for neonatal sepsis
- May be asymptomatic or nonspecific signs: Irritability, drowsy, apnea, respiratory distress, poor perfusion, thermal instability, vomiting, poor feeding, seizures, etc.
- Subtle markers: Core-axillary temperature mismatch, fluctuating temperature, unexplained tachycardia, changing body color, upcoming direct jaundice, unexplained metabolic acidosis
- Severe sepsis: Sclerema, bleeding tendency, cyanosis, grunt, abdominal fullness or redness, persistent gastric residue, neck retractions, bulging fontanel, thrombocytopenia
- YICSS Study identified seven clinical signs to predict possibility of sepsis in community settings (Table 1.2.2).
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TREATMENT AND COURSE
Supportive Care
- Nursing care: Minimal handling, minimize pricks, ensure skin integrity, change body posture, probe position every 4–6 hours, club interventions together, take pain control measures and ensure mother's participation in care of the newborn
- Ensure normothermia. Target temperature of 36.5°C
- Ensure normoxia. Target SpO2—88–94%
- Ensure euvolemia. Ensure urine output of >1 cc/kg/hour
- Ensure normotension
- Ensure normoglycemia. Ensure blood sugar >50 mg%
- Monitor every 3–4 hourly or as needed—sensorium, cry, activity, respiratory status (Down's score), circulatory status [temperature, heart rate (HR), pulse volume, respiratory rate (RR), urine output, color, extremity temperature, blood pressure, SpO2].
Definitive Care (Tables 1.2.3 and 1.2.4)
- Antibiotics
- Indicated for all sick infants and with positive sepsis screen
- Antibiotic therapy should be stopped after 36 hours if cultures are negative OR if two C-reactive protein (CRP) measurements are negative and if there are no further clinical signs of infection.
- Intravenous immunoglobulin (IVIG) (500 mg/kg) use is restricted to severe sepsis on case by case basis
- Management of shock. Fluid bolus should be considered on case by case basis if there is poor perfusion. Consider inotropes if the shock is fluid resistant. Dopamine is the drug of choice if the shock is hypotensive. Dobutamine is preferred if there is myocardial involvement. Consider increments in inotrope dose based on clinical response
- Steroids are restricted to inotrope resistant shock.
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DIFFERENTIAL DIAGNOSIS
- Viral infection
- Metabolic (electrolyte imbalance, hypoglycemia, etc.)
- Polycythemia
- Surgical causes (tracheoesophageal fistula, congenital diaphragmatic hernia, intestinal obstruction, etc.)
- Malformation (isolated cleft palate, congenital lung cyst, etc.)
- Meconium aspiration
- Inborn error of metabolism
- Congenital heart defect.
DIAGNOSIS
- Blood culture is gold standard for diagnosis of bacterial sepsis. Good practices to yield higher isolates on blood culture are:
- At least 1 mL blood sample
- Sample collected prior to antibiotic use
- Preparation of the site with an antibacterial solution (alcoholic solutions of chlorhexidine, iodine, or povidone-iodine) and cleansing for 30 seconds or two consecutive cleansings
- Cerebrospinal fluid (CSF) study if blood culture is positive or suspected meningitis
- Sepsis screen (Table 1.2.5) is indicated if sepsis is doubtful. It is performed after 12 hours of admission and repeated 24–48 hours later. It is not a substitute for blood culture.
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In Late onset sepsis evaluation in addition to above tests should include urine routine/culture and CSF study.
PROGNOSIS AND PREVENTION (TabLE 1.2.6)
Long-term follow-up of survivors is required due to risk of poor growth and poor neuro-developmental outcome.
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1.3 PROLONGED HYPERBILIRUBINEMIA
DEFINITION
- Jaundice beyond 14 days
- Secondary to raised indirect or direct bilirubin (cholestasis: Direct fraction > 2 mg% or > 15% of total bilirubin).
ETIOLOGY
Table 1.3.1 shows causes of prolonged hyperbilirubinemia.
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EPIDEMIOLOGY
- Up to 15% newborns develop prolonged jaundice
- Common in preterm
- Neonatal cholestasis: Affects 1 in 2500 live births. Constitutes 30% of hepatobiliary disorders in India. Average age of presentation is 3.5 weeks
- Cholestasis: Idiopathic neonatal hepatitis (26%), extrahepatic biliary atresia (26%), infection (12%), associated with TPN (6.5%), metabolic disease (4.3%), α1-antitrypsin deficiency (4.1%), perinatal hypoxia/ischemia (4%).
SIGNS AND SYMPTOMS
- Spectrum of presentation: Asymptomatic to acute liver cell failure, ascites, bleeding tendency and multiorgan dysfunction
- Cholestasis: High colored urine, clay stools, need urgent workup
- Intrauterine infection (e.g. TORCH): Weight loss, pallor, hepatosplenomegaly, petechiae, ecchymoses, chorioretinitis, thrombocytopenia, intrauterine growth restriction (IUGR), congenital anomaly
- Metabolic disorder: Consanguinity, previous siblings affected, abnormal body or urine odor, unexplained deaths, dysmorphism
- Inherited hemolytic disorders, inborn errors of metabolism or genetic syndromes: Family history of jaundice
- Fundus evaluation: It may give a clue.
TREATMENT AND COURSE
Indirect Hyperbilirubinemia
- Phototherapy: Rarely indicated
- Treatment: Directed towards cause.
- Breast milk jaundice: Benign, self-limiting. No role of withholding breast feeds.
- Congenital hypothyroidism: Early treatment can prevent intellectual delay.
Direct Hyperbilirubinemia
- Urgent detection and management of surgical cause within eight weeks for better outcomes
- Supportive care: Supplementation (Table 1.3.2)
- Liver transplant is last option.
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DIFFERENTIAL DIAGNOSIS
Refer Table 1.3.1.
DIAGNOSIS
- Breast milk jaundice: Diagnosis of exclusion
- Cholestasis: Elevated direct bilirubin USG, HIDA scan, liver biopsy or intraoperative cholangiogram.
Further Tests
Table 1.3.3 shows further tests.
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PROGNOSIS AND PREVENTION
- Up to 60% babies with idiopathic neonatal hepatitis recover completely
- Up to 30% newborns with cholestasis progress to liver cirrhosis, chronic liver disease death
- Adverse prognostic features: Acholic stools, biliary features on liver biopsy, firm hepatomegaly, positive family history
- Prompt diagnoses of treatable causes have better outcomes. Metabolic (galactosemia, tyrosinemia), endocrinal (congenital hypothyroidism, hypopituitarism), infections (malaria, congenital syphilis, toxoplasmosis, sepsis), surgical (choledochal cyst, biliary atresia).
1.4 HYPOGLYCEMIA IN NEWBORN
DEFINITION
- Hypoglycemia is defined as low blood sugar; (and resultant) low “brain sugar” causes permanent damage to the neurodevelopment of the child
- There is no single value of blood sugar that can define what is low for all situations.
- In a healthy term baby with no risk factors—35 mg/dL
- Sick babies (or on >10 mg/kg/minute of dextrose infusion) —60 mg/ dL
- Pediatric Endocrine Society recommends values of 50 mg/dL in first 48 hours and 60 mg/dL after that
The values at which this damage to brain may happen is dependent on:
- Gestation of the baby
- Comorbidities of brain (asphyxia, meningitis)
- Intactness of blood sugar metabolism (body stores, feeding, insulin regulation and gluconeogenesis).
ETIOLOGY
Babies at-risk of hypoglycemia:
- Sick neonates/all babies on intravenous fluids
- Infant of diabetic mothers
- Preterm neonates/post-term
- Small and large for gestational age
- Asphyxia
- Transient hyperinsulinemia due to stress
- Primary disorders of glucose metabolism
- Primary hyperinsulinemia
- Congenital adrenal hyperplasia
- Inborn errors of metabolism—glycogen storage disease, medium chain acyl-CoA dehydrogenase deficiency.
EPIDEMIOLOGY
- First 48 hours of life—Babies at risk (mentioned above) must be screened periodically 6th hourly or more often
- All sick neonates must have blood sugar monitored as a part of the primary survey. Any hypoglycemia that is severe (needs intravenous fluids), symptomatic (lethargy, seizures, apnea, jitteriness), recurrent or persistent after 3 days of life must be considered pathological and evaluated for etiology.
SIGNS AND SYMPTOMS
Symptoms of hypoglycemia are grouped as:
- Neuroglycopenic—lethargy, seizures, apnea
- Adrenergic—jitteriness, sweating, tachycardia.
Note the setting that led to hypoglycemia like prematurity, low birth weight, infant of diabetic mother, sepsis, asphyxia, etc. as these determine the expected course of hypoglycemia.
TREATMENT AND COURSE
- Asymptomatic babies with blood sugar values below “normal”, detected by screening, are offered breast milk (preferred)/formula milk and blood sugars measured every 15–30 minutes till blood sugar reach safe values
- Symptomatic babies/babies with blood sugar <25 mg/dL are given a 2 mL/kg bolus of 10% dextrose, followed by 10% dextrose infusion at 80 mL/kg/day (6 mg/kg/minute). Blood sugars measured every 15–30 minutes till blood sugar reach safe values, the infusion is increased by 2 mg/kg/minute, if the sugar values are below “normal”. If dextrose infusion of 12.5% or more is required, a central line must be inserted11
- The dextrose infusion is tapered every 6–12 hours, if the values are over 60 mg/dL
- If dextrose infusion of 10 mg/kg/minute is required—hydrocortisone (or dexamethasone)
- Diazoxide is used, if high glucose infusion rate (GIR) is required and blood sugar remains unstable. If still not responding, octreotide is tried. Nifedipine can be tried in most difficult cases
- Glucagon can rapidly improve glucose levels in an emergency.
DIFFERENTIAL DIAGNOSIS
Hypoglycemia must be excluded in all babies with encephalopathy, in all sick babies.
DIAGNOSIS
- Point of care testing by glucose oxidase method
- Practical tips: The blood spot should be collected without contamination with antiseptic and should cover the sensing spot completely
- Confirmation of low sugar is done in the lab using spectrophotometry. The sample must be processed without delay.
Values of blood sugar for intervention: 50 mg/dL.
PROGNOSIS AND PREVENTION
- Symptomatic hypoglycemia—high risk of disability—seizures, intellectual disability, cortical visual impairment (typical area of injury is parieto-occipital lobes)
- Asymptomatic hypoglycemia—much lower risk
- Prevention involves supporting lactation and periodic monitoring in high risk neonates.
1.5 RESPIRATORY DISTRESS SYNDROME IN PRETERM
DEFINITION
Respiratory distress syndrome (RDS) refers to onset of respiratory distress (retractions, grunting, tachypnea) within 6 hours of birth in a preterm baby.
ETIOLOGY
- Respiratory distress syndrome is a clinical diagnosis
- Surfactant insufficiency due to prematurity
- Congenital pneumonia
- Transient tachypnea of newborns.
EPIDEMIOLOGY
- Incidence of RDS is dependent on gestation
Gestation (weeks) | <28 | 28-32 | >33 |
Babies with RDS (%) | 60-80 | 30-40 | <10 |
- Antenatal steroids decrease RDS incidence and severity
- Coexisting early onset neonatal sepsis can present as RDS (congenital pneumonia).
SIGNS AND SYMPTOMS
- Retractions are the most important determinants of severity and actions to be taken [continuous positive airway pressure (CPAP)]
- Grunting may be heard without stethoscope (severe) or only with stethoscope (mild)
- Cyanosis (need for oxygen)
- Mild—pink (saturation 90 or more) without supplemental oxygen
- Moderate—cyanosis corrected with 30–40% oxygen by mask/hood box
- Severe—saturation <90/cyanosis even with 30–40% oxygen
- Tachypnea [respiratory rate (RR)] more than 80/minute (severe) and 60–80/minute (mild); RR is subject to errors, as babies have irregular breathing pattern
- Decreased air entry (subjective); asymmetry of breath sounds may give more information
- Some RDS scores include gestation
- Severe RDS may present with apnea.
TREATMENT AND COURSE
Treatment options would depend on severity of respiratory distress, anticipated severity of illness and general condition of baby:
- CPAP
- Babies with moderate respiratory distress (retractions, grunt, cyanosis corrected with 30–40% oxygen)
- Gestation more than 28 weeks
- Good respiratory efforts, tone, perfusion; no apnea, not needing extensive resuscitation at birth (chest compression, medications)
- Initiate CPAP in labor room with T-piece resuscitator, if preterm baby has signs of RD (some recommend prophylactic CPAP for extreme preterm babies)
- INSURE— Intubate, give surfactant, extubate within 15 minutes and put back on CPAP— this is the best care plan for babies with severe RDS or those progressing in symptoms on CPAP
- Intubation, mechanical ventilation—babies with recurrent apnea, cardiovascular instability
- HHHFNC (heated humidified high flow nasal cannula) is inferior to CPAP as initial support for RDS; is equally effective in support of babies extubated after invasive ventilation for RDS
- Oxygen by hood/mask must be used only transiently to assess babies with RDS, or while CPAP is being organized (if baby was not labor room CPAP/T-piece resuscitator).
Early use of CPAP and surfactant when indicated results in dramatic improvement of RDS. If babies are not off respiratory support, the following are considered:
- Comorbidity—infection
- Extreme preterm
DIFFERENTIAL DIAGNOSIS
- Congenital pneumonia
- Transient tachypnea of newborn
- Rarely—air leaks.
DIAGNOSIS
- Clinical findings
- Chest X-rayMild-moderate: Air bronchogram, low volume lungs, haziness of cardiac and liver bordersSevere: Air bronchogram, white-out (one cannot make out lung, heart and liver shadows as separate)
- Arterial blood gas: Respiratory acidosis and hypoxia
- Infection markers (blood culture) and CRP are negative.
PROGNOSIS AND PREVENTION
- Respiratory distress syndrome resolves rapidly and completely if CPAP (and surfactant in some, mechanical ventilation in lesser) is started early and given effectively with good nursing care
- Early enteral feeding, hypothermia and prevention of infection are key to good outcomes
- Extreme preterm babies may evolve to bronchopulmonary dysplasia and may be respiratory support for very long duration; this is due to immaturity of lung.
1.6 NEONATAL SHOCK
- Shock is a critical clinical disorder characterized by decreased end organ perfusion
- It should be recognized before onset of hypotension (i.e. blood pressure below the 5th percentile for gestation and postnatal age) which is a late or advanced sign of shock.
ETIOLOGY
- Hypovolemic shock
- Blood loss, e.g. antepartum hemorrhage (e.g. abruptio placenta, placenta previa), twin to twin transfusion, bleeding due to vitamin k deficiency, slipped cord ligature, birth trauma, coagulation disorders, etc.
- Fluid loss, e.g. vomiting, diarrhea
- Distributive shock, e.g. septicemia, hydrops, toxic shock syndrome
- Cardiogenic shock
- Decreased myocardial contractility, e.g. myocarditis, electrolyte imbalance, drug toxicity
- Structural heart disease, e.g. hypoplastic left heart, aortic stenosis, coarctation of aorta, transposition of great vessels, cardiomyopathy
- Rhythm disorders, e.g. supraventricular tachycardia, congenital heart block
- Obstructive shock, e.g. tension pneumothorax, pericardial effusion, postsurgery
- Neurogenic shock, e.g. asphyxia, intracranial hemorrhage, meningitis, vascular malformation, space occupying lesions, etc.
EPIDEMIOLOGY
- Shock is most prominent risk factor for death in neonatal sepsis
- Shock is more common in late onset sepsis, preterm, very low birth weight (VLBW) babies.
SIGNS AND SYMPTOMS
- No single sign pathognomic of shock (Table 1.6.1)
- Poor perfusion needs to be recognized early
- Hypotension: In compensated shock it may take hours for hypotension to develop
- Cardiopulmonary failure develops in few minutes in hypotensive shock
- Shock is a dynamic condition hence a trend of signs is far more informative.
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TREATMENT
- Supportive care: Strict asepsis, monitoring of vitals, normothermia (T 36.5oC), normoglycemia (B sugar > 50 mg%) normoxia (SpO2 > 88–94%).
- Oxygen: Initiate and titrate dose based on pulse oximetry. Mechanical ventilation if inability to maintain SpO2 > 90% despite 100% oxygen.
- Fluid bolus: Empiric bolus of 10 cc/kg of RL may be given. Avoid > 20 cc/kg if no history of fluid or blood loss. The routine use of fluid bolus is potentially harmful in preterm.
- Inotropes (Table 1.6.2)
- Dopamine: Most effective, first drug of choice
- Dobutamine: If cardiac involvement
- Epinephrine, norepinephrine: Nonresponsive shock
- Milrinone: Reduces afterload in cardiac dysfunction
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- Steroids: Inotrope resistant shock
- Treatment of the cause (Table 1.6.3).
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DIFFERENTIAL DIAGNOSIS
Asphyxia, metabolic (e.g. hypoglycemia, dyselectrolytemia), inborn error of metabolism, iatrogenic, drug induced, birth trauma.
DIAGNOSIS
- Based on history, constellation of signs and clinical course
- Hypotensive shock if low blood pressure
- Bedside 2D echo provides physiologic cardiac status, blood flows shunt pathology
- Specific investigations confirm the etiology.
PROGNOSIS AND PREVENTION
- Best outcomes: If early recognition of poor perfusion and prompt action prior to development of hypotension.
1.7 APNEA OF PREMATURITY
DEFINITION
Apnea of prematurity (AOP) is cessation of breathing for more than 20 seconds and/or accompanied by hypoxia or bradycardia by a premature newborn.
ETIOLOGY
- Apnea of prematurity is a ‘diagnosis of exclusion’ in preterm newborns
- Maturational disorder of central nervous system due to abnormal control of breathing
- Common causes (Table 1.7.1).
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EPIDEMIOLOGY
Apnea of prematurity is inversely proportional to gestation, with incidence of 80% in <30 weeks, 50% at 30–32 weeks and 10% of at 34 weeks.
SIGNS AND SYMPTOMS
- Significant apnea: Abrupt onset of periods of absent breathing (>20 sec) or less than 20 seconds with bradycardia or hypoxia
- Classically seen on day 2–4 days (80%), rarely on day 1 or beyond 10 days
- Infant otherwise well in between the episodes
- Search for pathological causes if increase in frequency or severity:
- Anemia (e.g. tachycardia, pallor)
- Plethora, infection (e.g. rash, icterus, bleeding tendency, poor peripheral perfusion)
- Heart disease (e.g. cyanosis, murmur, unexplained hepatomegaly, cardiomegaly, weak pulses)
- Central nerve system (CNS) disorder (e.g. encephalopathy, hypo or hypertonia, seizures, tense anterior fontanel, color change)
- Thermal instability, upper airway anomaly, work of breathing (e.g. bradypnea-tachypnea, chest indrawing, grunt, hypoxia)
TREATMENT AND COURSE
- All newborns ‘at risk’: <34 weeks or <1800 g should be continuously monitored by pulse oximeter with saturation alarm and heart rate limits set (SpO2 88–94%)
- Nil by mouth (NBM) for 24 hours of apneic spell.
General Measures
- Neutral thermal environment
- Nurse the baby in prone or lateral and head-up position
- Ensure patency of airway (‘sniffing’ position, shoulder roll, suction)
- Tactile stimulation—slapping feet, rubbing back
- Oxygen supplementation, target SpO2: 88–94%
- Support with positive pressure ventilation (PPV).
Drug Therapy
- Medications if three or more significant episodes (Table 1.7.2)
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- Doxapram is rarely required for AOP. Contraindicated in 1st week of life or if bilirubin is high.
- Respiratory support
- Noninvasive respiratory support if apnea persists despite drugs and if there is spontaneous respiration, e.g. CPAP or noninvasive positive pressure ventilation (NIPPV) or high-flow nasal cannula
- Intubation and mechanical ventilation. If there are no spontaneous respiration
DIFFERENTIAL DIAGNOSIS
Hypoxia, sepsis, IVH, NEC, PDA, BPD, fungemia, electrolyte imbalance, thermal instability, hypoglycemia, hypocalcemia or inborn errors of metabolism.
DIAGNOSIS
- Breathing pauses of >20 sec or associated with bradycardia or oxygen desaturations, clinical detection is too late and only severe or prolonged apneas can be detected
- Baseline tests to rule out underlying causes: Sepsis screen, blood culture, blood sugar, serum calcium, serum electrolytes, cranial USG, 2D Echo, X-ray chest, ABG, etc.
PROGNOSIS AND PREVENTION
- Apnea resolves in majority by 36 weeks (up to 44 weeks in < 28 weeks) postconceptual age
- Apnea per se does not alter the neurologic outcome. Presence of comorbid conditions and complications decide the long-term outcome
- Prevention of prematurity is the best measure
- Awareness, early detection, meticulous monitoring
- Infants less than 30 weeks may benefit from caffeine within 24 hours of age.
1.8 NEWBORN SCREENING
Screening: Proven, cost-effective coordinated, evidence-based strategy for a defined population.
METABOLIC SCREENING
- About 25–30% unexplained deaths have a metabolic/genetic cause
- Aim: Identify infants ‘at risk’ for metabolic disorders before onset of signs/symptoms
- When: In full-term healthy infants at 72 hours of age. If tests done before 24 hours of age, repeat after two weeks
- Sampling (Table 1.8.1)
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- Strategy to screen
- All newborns, in low resource settings (congenital hypothyroidism, congenital adrenal hyperplasia, G6PD deficiency)
- ‘High risk’ newborns (phenylketonuria, homocystinuria, alkaptonuria, galactosemia, sickle-cell anemia, other hemoglobinopathies, cystic fibrosis, biotinidase deficiency, Maple syrup urine disease, medium-chain acyl-coenzyme A dehydrogenase deficiency (MCAD), tyrosinemia, fatty acid oxidation defects)
- Interpretation
- Invalid: Need to repeat test
- Negative: Does not guarantee future onset of disease
- Positive: Need for confirmation test. Does not indicate ‘disease’/need for therapy
- Special conditions
- Specimen: Take before blood transfusion
- Premature/sick infants: Seven days of age
- Newborn less than 32 weeks: Repeat test at 28th day/discharge
- After starting feedings
- Parenteral nutrition not contraindicated.
NEONATAL JAUNDICE SCREEN
- Aim: Identify newborns ‘at risk’ for hyperbilirubinemia
- Timing: At discharge
- Strategy
- Hour specific bilirubin nomogram (Fig. 1.8.1)
- How: Plot bilirubin value on chart
- Interpretation
- Below low risk zone (<40th centile): Risk negligible, can be discharged
- In intermediate zone (40–95th centile): 6.4% risk, assure follow-up re-evaluate 24 hours later
- High risk zone (>95th centile), 39.5% risk. Repeat bilirubin 8 hours later.
- Limitations: Not applicable— < 35 weeks, 0–24 hours, hemolysis
- 20Transcutaneous bilirubinometer (Fig. 1.8.2)
- Place across forehead/sternum. Plot reading on nomogram
- Limitations: Not applicable—<35 weeks, <24 hours of life, under phototherapy
- Clinical risk assessment (Table 1.8.2).
- Presence of one/more risk factors: Scheduled follow-up.
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PULSE OXIMETER SCREEN
- Aim: Detection of critical congenital heart defects (CCHD)
- When: At discharge/after 24 hours of birth
- Tool: Pulse oximeter with neonatal probe
- How: Place pulse oximeter on right hand, foot
- Interpretation (Table 1.8.3)
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- 21Conditions diagnosed: Cardiac lesions that require surgery or cardiac catheterization within first month of life to prevent death like hypoplastic left heart, pulmonary atresia, total anomalous pulmonary venous connection, transposition of great arteries, tetralogy of Fallot, tricuspid atresia, truncus arteriosus communis
- Conditions missed: Ebstein's anomaly without right-to-left shunt, aortic stenosis without PDA, coarctation of aorta, interrupted aortic arch, pulmonary stenosis, left to right shunts
- Limitations:
- Normal screen at birth: Does not eliminate possibility of CCHD
- Hypothermia, deep sleep or agitation may give abnormal readings
- Different averaging time influence readings.
NEWBORN HEARING SCREEN
- Aim: To identify hearing loss at earliest, intervene before 6 months of age
- Test: Otoacoustic emission (OAE)
- When: At discharge
- For: Detection of cochlear function
- Technique: A soft, disposable probe tip gently inserted into external ear canal. A sound stimulus at a moderate intensity level is generated. A miniature microphone within probe assembly detects OAE-related sound. The algorithms analyze recorded sound
- Interpretation: Pass, refer/inconclusive.
- Pass: Does not rule out hearing loss
- Refer: Need detailed hearing assessment
- Inconclusive: Repeat test
- Advantages: Inexpensive, noninvasive, brief record time, objective, not affected by cognition, behavior, cooperation, motion, artifacts, technically easy, sedation, audiologist not required
- Limitations
- Background noise interferes testing, needs noiseless room
- Debris, wax, fluid in middle ear interferes results
- A screening tool, not a diagnostic modality
- A normal test does not rule out late onset hearing loss
- Does not provide, type, degree of hearing loss
- Some false positives.
RETINOPATHY OF PREMATURITY SCREEN
- Aim: Early detection of retinopathy to prevent visual loss, myopia, strabismus, visual impairment, permanent blindness
- When: Day 30, for < 28 weeks/<1200 g at 2–3 weeks of age
- Who: < 34 weeks/<2 kg/>34 weeks with unstable course
- Preparation: Avoid feed 30 minutes prior, dilate pupils (topicamide 0.8% + phenylepherine HCl 5% diluted in 1:1 ratio with a tear substitute, methyl cellulose). Put 5 drops every 5 minutes × 3. Topical anesthetic eye drops (proparacaine), tear substitutes keep ready
- Procedure: By trained ophthalmologist indirect ophthalmoscope, hand-held 20 D lens
- Interpretation: Revised International classification of retinopathy of prematurity (ROP). (IRCOP, 2005)
- Frequency of screening: By guidelines of IRCOP/ophthalmologist
SCREENING FOR DEVELOPMENTAL DYSPLASIA OF HIP
- Aim: improve hip development in infancy, early childhood, to prevent subsequent functional impairment
- When: At OPD visits
- Whom: Breech position in utero, females firstborn, positive family history
- Tests:
- Barlow maneuver (adduct hip to midline, gently apply posterior force)
- Ortolani maneuver (abduct hips, apply anterior-directed pressure at greater trochanters)
- Interpretation: Positive, if femoral head subluxes, a clunk felt (Barlow) or relocates with a distinct clunk (Ortolani)
- Diagnosis: Confirmation by static and dynamic USG study of hip if <6 months of age
- Drawbacks
- Sensitivity of maneuvers: 54%. Need tests to confirm
- Severe dislocation: Not reducible, may not be picked up
- Not applicable to infants, child
- Sequelae of developmental dysplasia of hip (DDH): Osteoarthritis of hip
- Endpoint of screening: Child reaches walking age.
1.9 NEONATAL SEIZURES
DEFINITION
Neonatal seizures:
- Seizures in a neonate are manifestation of severe encephalopathy; rarely they are epilepsy of neonatal origin
- Seizures are neurologic disturbances of sudden onset
- Seizures may be motor (tonic, clonic), eye-movements—fixed gaze, apnea, abrupt changes in heart rate
- Electroencephalography (EEG) monitoring, can confirm that the abrupt change in neurologic state is a seizure
- Many abnormal movements in neonates mimic seizure
- A few seizures may manifest only on EEG and may not be noticed clinically.
ETIOLOGY
- Symptomatic seizures—secondary to severe encephalopathy
- Hypoxic ischemic encephalopathy (HIE)
- Perinatal stroke
- Infections—meningitis, intrauterine infections
- Intracranial hemorrhage—especially intraventricular hemorrhage in preterm
- Hypoglycemia
- Hypocalcemia, hypomagnesemia, hyponatremia
- Congenital malformations of brain
EPIDEMIOLOGY
- The most common cause of seizures depends on state of perinatal care
- In areas of high neonatal mortality (low-resources)—perinatal asphyxia is the most common, followed by infections
- In areas of lowest neonatal mortality, stroke, malformations and metabolic disorders would be most common.
SIGNS AND SYMPTOMS
- Commonest symptoms are abnormal movements—clonic movements, tonic posturing—the typical march of seizures in adults is often not seen
- Abnormal eye movements—fixed gaze, blinking of eyes
- Subtle movements—sucking, chewing and smacking movements of mouth
- Apnea
- Complete loss of tone
- Autonomic changes—abrupt changes in heart rate, breathing pattern.
Seizures have multiple causes and hence the clinical syndrome is variable; most accept a seizure activity of 3 minutes or more as indication to treat.
TREATMENT AND COURSE
- Stabilize airway, breathing
- Check blood sugar and treat if low—2 mL/kg of dextrose followed immediately with dextrose infusion at 6 mg/kg/minute
- Check ionized calcium (if report can be available immediately); if not, empirically treat with 2 mL/kg calcium gluconate push slowly with caution of risk of bradycardia and extravasation
- Consider antiepileptic drug (AED), if seizures last 3 minutes or more after correction of glucose and calcium
- Most frequently used 1st line AED is phenobarbitone
- Recent concerns on long-term safety of phenobarbitone has led to evaluation of newer AED and levetiracetam seems to be a safe AED
- Phenytoin is the first line AED in pediatric practice, hence, many use this as first line; which is equally effective and safe
- If response to a single dose of AED is not noted, the next AED must be given after ensuring airway, breathing and circulation
- Treat correctible factors like low sugar, low calcium, intracranial hemorrhage
- Second AED commonly used are phenobarbitone, phenytoin, midazolam and many more
- Need for second AED indicates severe underlying encephalopathy.
DIFFERENTIAL DIAGNOSIS
DIAGNOSIS
- Clinical diagnosis is subject to errors; but, most clinicians do not have access to EEG when the seizure is suspected
- EEG monitoring (or amplitude EEG) is available bedside in most advanced care centers and initiated on neonates with encephalopathy to make a better diagnosis
- Lab tests for underlying cause—blood sugars, calcium, electrolytes, CSF examination
- Screening for metabolic disorders
- Imaging:
- Neurosonogram: Ideal where IVH is common
- MRI: To complete diagnosis of HIE
- CT scan: Preferred for intracranial hemorrhage in term born babies, to detect calcification. CT has disadvantages of radiation exposure; but, it is faster than MRI and is used in unstable neonates.
PROGNOSIS AND PREVENTION
- Depends mostly on the underlying cause
- Late onset hypocalcemia mostly has favorable outcome
- Hypoxic ischemic encephalopathy, hypoglycemia, malformation, infections are associated with more than 50% risk of neurodisability
- Prognosis is poor if the EEG background is isoelectric or shows burst suppression in the interictal period
- Preterm babies with seizures have poor prognosis
- In HIE, early onset seizures (within 12 hours) and difficult to control seizures have poor outcomes.
BIBLIOGRAPHY
- Thakre R, Murki S. Protocols in Neonatology: Indian Academy of Pediatrics: Neonatology Chapter, 2nd edition. Jaypee Brothers Medical Publishers, New Delhi, 2019.
- Murki S, Thakre R. OSCE in Neonatology: A Guide Book. Indian Academy of Pediatrics: Neonatology Chapter, 1st edition. Jaypee Brothers Medical Publishers, New Delhi, 2017.