18 Neonatology (NICU)

18.1 APGAR Scoring

0 1 2
HR <60 60-100 >100
Color Blue throughout Pink body & blue extremities All pink
Respiratory effort No effort Weak cry, hypoventilation Strong cry
Tone Limp Some flexion w/o active movement Active movement
Reflex irritability No response Grimace Cry/cough/sneeze

18.2 Neonatal Respiratory Disorders & Delivery Room Pathology

  • Can be divided into:
    • Upper airway blockage (choanal atresia, pharyngeal airway malformation)
    • Impaired lung function

18.2.1 Choanal Atresia

18.2.1.1 History

Pink when crying, cyanotic when quiet. Inability to pass NG tube in one or both sides

18.2.1.2 Management

Oral airway, intubation

18.2.2 Pharyngeal Airway Malformation

18.2.2.1 History

Persistent Retractions, poor aeration

18.2.2.2 Management

Prone positioning, posterior nasopharyngeal tube

18.2.3 Congenital Diaphragmatic Hernia (CDH)

18.2.3.1 History

Assymetric lung sounds, cyanosis with bradycardia, scaphoid abdomen.

18.2.3.2 Diagnosis

Most likely on prenatal imaging in patients with prenatal care. Postnatally diagnosed with CXR

18.2.3.3 Management

Intubation, avoid positive pressure! Place orogastric tube.

18.2.4 Pleural Effusion

18.2.4.1 History

Diminished aeration with poor osygenation/ventilation

18.2.4.2 Management

Intubation, needle thoracentesis +/- chest tube. Volume expansion if hemodynamically unstable. Fluid analysis to determine type and source of fluid.

18.2.5 Pneumothorax

18.2.5.1 History

Persistent cyanosis, hypoxemia, +/- bradycardia associated with respiratory distress

18.2.5.2 Diagnosis

CXR

18.2.5.3 Management

Needle thoracentesis immediately, chest tube if recurrent

18.2.6 Meconium Aspiration

18.2.6.1 History

Meconium stained fluid, respiratory distress and/or apnea if severe

18.2.6.2 Diagnosis

CXR

18.2.6.3 Management

Can deep suction upper airway. Tracheal suctioning not recommended. Intubation per NRP

18.2.6.4 Complications

Can cause lung inflamation and direct surfactant inactivation and one of the causes of persistnet pulmonary hypertension, there is a range of severity but can be quite severe!

18.2.7 Persistent Pulmonay Hypertension (PPHN)

18.2.7.1 History

Asphyxia, mecoumium aspiration, intrinsic lung disease

18.2.7.2 Clinical Manifestations

Hypoxemia, hypotension

18.2.7.3 Diagnostics

CXR with decreased pulmonary vasculature. ECHO with increased R->L shunting.

18.2.7.4 Management

  • Ultimate goal is to decrease the pulmonary vascular resistance and increase pulmonary blood flow.
  • Oxygenation Index (OI): Helpful numeric index evaluating oxygenation to direct management decisions
    • OI = FiO2 x MAP / PaO2

18.2.8 Respiratory Distress Syndrome (RDS)

18.2.8.1 Etiology

Surfactant deficiency, common in premature infants

18.2.8.2 Symtpoms

Hypoxia with respiratory distress

18.2.8.3 Diagnostics

CXR with ground glass opacities, low lung volumes, air bronchograms

18.2.8.4 Management

  • CPAP or if severe respiratory distress/apnea intubation
  • Surfactant administration if intubated. Can give 2 doses if still intubated 12 hrs after the 1st dose
  • Minimize barotrauma and FiO2

18.2.9 Transient Tachypnea of the Newborn (TTN)

18.2.9.1 Etiology

Delayed retention of amniotic fluid

18.2.9.2 History

Typically a term infant, higher risk with birth by C-section.

18.2.9.3 Clinical Manifestations

Tachypnea, respiratory distress, +/- hypoxemia

18.2.9.4 Diagnosis

CXR with prominent vasculature and fluid in the fissures

18.2.9.5 Management

Supportive care, usually improves in 4-6 hrs. If O2 needs or symptoms last longer than 24 hrs, question diagnosis.

18.3 Neonatal Cardiology

NOTE: See Cardiology chapter for full details.

18.3.1 Blood Pressure for Premature Infants

  • Can be controversial as there are no normatives in the literature, but rough rule of thumb:
    • First 1-2 DOL, MAP = GA (i.e. 24wk infant → goal MAP >24)
      • Some evidence that MAP should be > 30 mmHG even for ELBW
    • After first few DOL, goal MAP = GA + 5
    • For infants w/ PPHN, goal MAP should be based on pulmonary blood flow and urine output, even if it requires higher MAPs than typical for GA (sometimes 40-50 mm Hg)
  • Key is to monitor urine output, pulses, perfusion, trends in BUN/Cr

18.3.2 Patent Ductus Arteriosus (PDA)

18.3.2.1 Etiology

Failure of ductal tissue to close in the premature infant. Affects about 60% of infants <28 weeks.

18.3.2.2 Clinical Manifestations

  • Continuous machine-like murmur
  • Hypotension, widened pulse pressure, hyperactive precorium
  • Worsening oxygenation and ventilation, secondary to pulmonary over-circulation
  • Metabolic acidosis

18.3.2.3 Diagnosis

Echocardiogram

18.3.2.4 Management

  • Medical therapy: Indomethacin or ibuprofen or tylenol
    • Generally contraindicated if large IVH, severe oliguria, or NEC
  • Surgical ligation
  • Watch & wait: w/ symptomatic support (i.e. ventilator management, pressors for MAP support)

18.4 Neonatal Hematology

18.4.1 Anemia

18.4.1.1 Definition

Depends on gestation and chronologic age

18.4.1.2 Differential

  • Iatrogenic: Frequent blood draws, surgical/procedural blood loss
  • Hemorrhagic: Placental abruption, umblical cord disruption at delivery, head trauma (subcaleal, cephalohematoma), NEC, twin-twin transfusion, IVH
  • Hemolytic: Rh incompatability, ABO incompatability

18.4.1.3 Work-up

  • CBC, retic, type and Coombs, smear, bilirubin, HUS or head imaging if risk for IVH
  • At birth: Delivery history, PE, Kleinhauer-Betke on mother (determines if fetal blood is in maternal circulation) in addition to above

18.4.1.4 Management

  • NOTE: Transfusion criteria for term and premature infants does not have robust data and is controversial. It tends to be facility dependent.
  • Preterm:
    • If intubated and acutely ill, Hct 35-40
    • If “feeding and growing,” Hct >30 w/ good reticulocyte
  • Term:
    • If acultely ill, consider transfusing to goal Hct >40
    • If hemodynamically stable, goal Hct >25

18.4.2 Polycythemia

18.4.2.1 Definition

Hct >65

18.4.2.2 Differential

Increased fetal production, placental insufficiency, thyrotoxicosis, gestational diabetes (GDM), genetic disorders (e.g. Trisomy 21, Beckwith-Wiedemann), hypertransfusion, delayed cord clamping, twin-twin transfusion

18.4.2.3 Work-up

  • CBC, monitor for hypoglycemia, follow bili & electrolytes
  • Monitor especially if there are neurologic symptoms or respiratory distress

18.4.2.4 Management

Partial exchange transfusion w/ normal saline, ideally w/ UVC

  • Indications: Hct >65 w/ symptoms, >70 and asymptomatic

18.4.3 Thrombocytopenia

18.4.3.1 Definition

Plt <150

18.4.3.2 Differential

  • Increased destruction/consumption: Autoimmune, alloimmune (NAIT), infection/DIC/NEC, drug-induced/toxicity, hypersplenism, Kasabach-Merrit Syndrome, following transfusion
  • Decreased production: Thrombocytopenia-absent radius, Fanconi anemia, Trisomy 13, 18, 21
  • Miscellaneous: Asphyxia, pre-eclampsia, Type 2B Von-Willebrand

18.4.3.3 Work-up

  • Labs: Repeat platelet count, coagulation studies
  • Imaging: Consider HUS
  • Exam for evidence of bleeding
  • Maternal history including maternal platelet count

18.4.3.4 Management

Depends on etiology, symptoms, and upcoming needs (i.e. procedures)

  • Platelet goals:
GA Symptomatic Asymptomatic
Term >50-100k >20-30k
Pre-Term >100k >50k
  • Management specific to Neonatal Alloimmune Thrombocytopenia (NAIT):
    • Goal plts >20-30k if no active bleeding (use antigen negative platelets to transfuse)
    • Check HUS
    • Consider steroids or IVIG
    • Maternal platelet typing

18.5 Neonatal Neurology

18.5.1 Interventricular Hemorrhage (IVH)

18.5.1.1 Pathophygiolosy

Blood vessel/blood brain barrier development is premature leaving very delicate, fragile blood networks

18.5.1.2 Screening

  • Screening criteria (indications for HUS): GA <32 wks, BW <1500g, low Hct, low plts, unstable BPs, prolonged hypotension, cardiopulmonary arrest, pneumothorax, asphyxia, pre/during ECMO
    • Timing: DOL 3, 7-10, 30, 60 (consider in first 24 HOL if very ill ELBW)

18.5.1.3 IVH Grading

  • Grade I: Germinal matrix hemorrhage (GMH)
  • Grade II: Intraventricular hemorrhage without ventricular dilation
  • Grade III: Intraventricular hemorrage with ventricular dilation
  • Grade IV: Grade III + parenchymal hemorrhage

18.5.2 Therapeutic Cooling

18.5.2.1 BWH Protocol

NOTE: Protocols are site-specific! This section reviews the BWH protocol. Access BMC info via the BMC Infonet.

  • Standard eligibility criteria:
    • > 34 wks gestation
    • Any one of the following:
      • Sentinel event prior to delivery
      • Apgar score < 5 at 10 min
      • Requires PPV, intubation, or CPR at 10 min
      • pH < 7.1 from cord or blood gas within 60 min of birth
      • Abmormal base excess < -10 meq/L from cord or blood gas within 60 min of birth
    • Any one of the following:
      • Neonatal encephalopathy score > 4
      • Seizure or clinical concern for seizure
  • Exclusion criteria:
    • Absolute contraindication: <34 wks gestation
    • Relative contraindications: Severe IUGR, <1750g, severe congenital anomalies/genetic syndromes/known metabolic disorders, major intracranial hemorrhage, overwhelming sepsis, uncorrectable clinically significant coagulopathy

18.5.2.2 Management

Site-specific as encompassed in respective protocols, but below are some general guides:

  • Cardiovascular monitoring
  • Total fluid goal of 60 ml/kg/day. Can do up to 10 mL/kg/day of eneteral feeding if clinically stable.
    • At BWH, infant will be on starter PN and then custom PN while cooled
  • Sedation: Morphine 0.05 mg/kg loading dose, followed by 0.01 mg/kg/hr infusion. Can decrease to 0.005 mg/kg/hr after 12 hrs.
  • Neuromonitoring
    • EEG for 24 hrs, can be switched to aEEG if EEG w/o seizures
    • HUS on admission
    • MRI on DOL 4 after re-warming, and after DOL 10-21
    • If leaving protocol early, consider MRI 24-48 hrs after rewarming
  • Seizures
    • Drug of choice: Phenobarbital 20 mg/kg loading dose, w/ serum level 2-12 hrs
    • 2nd choice: Fosphenytoin 20 mg/kg
    • 3rd choice: Midazolam 0.05 mg/kg IV one time followed by 0.15 mg/kg/hr for 12 hours then taper over 24 hrs
  • Lab monitoring (suggested)
    • On admission: Lactate, blood gas, CBC, PT/PTT/INR, fibrinogen, blood culture
    • At 12 hrs: BMP, Mg, ALT, AST

18.6 Neonatal Infectious Disease

18.6.1 Sepsis

18.6.2 TORCH infections

  • When to be concerned: IUGR/SGA (<10th% for age), failed hearing screen, blueberry muffin rash, hepatosplenomegaly, unexplained direct hyperbilirubinemia
  • Infections and how to diagnose them:
    • Toxoplasmosis: Newborn Screen (NBS)
    • Syphilis (other): Maternal screen
    • Rubella: Maternal screen
    • CMV: Urine CMV shell or Buccal CMV PCR
    • HSV: Maternal history or PCR/cultures from suspected lesions on baby. HSV PCR from blood/CSF.

18.6.3 Vertical Transmission

18.6.3.1 Hep B

See Newborn Nursery chapter

18.6.3.2 HIV

Call ID consult w/ maternal labs and history to initiate treatment AS SOON AS POSSIBLE!

18.7 Neonatal Endocrinology

18.7.1 Hypoglycemia

18.7.1.1 Definition

Goal glucose value depends on age:

  • 0-4 hours of life (HOL) = >40
  • 4-24 HOL = >45
  • 24-48 HOL = >50
  • Greater than 48 HOL = >60

18.7.1.2 Risk factors

Infant of diabetic mother (IDM), birth weight <2500g, SGA (<10%ile) or LGA (>90%ile), preterm (<37w) or post-dates (>42w), 5-min Apgar <7, maternal meds (beta blocker, terbutaline given to mom w/i 48 hrs of delivery, respiratory distress > 1hr, family history of hypoglycemia, congenital syndrome or midline abnormalities

18.7.1.3 Management

Depends on age and value:

  • If mild for age, can feed
  • If severe for age, consider D10W 2 mL/kg bolus and/or maintenance D10W at 60 mL/kg/day

18.8 Neonatal Gastroenterology

18.8.1 Emesis in an Infant

18.8.1.1 Differential

Medical vs. Surgical

Medical Surgical
- Anxiety, excitement
- Celiac disease
- CAH
- Improper feeding
- Inborn errors of metabolism
- Infection (sepsis, UTI, meningitis)
- Esophageal dysmotility
- Excessive crying
- Food allergies
- Gastroenteritis
- GERD
- Ingestion of maternal blood/mucous
- Kernicterus
- Milk protein allergy
- NEC
- Overfeeding		 Annular pacreas
- Appendicitis
- Atresia, stenosis, webbing
- Duplications
- Esophageal atresia
- Functional ileus
- Hernias
- Intussusception
- Malrotation w midgut volvulus
- Meconium ileus
- Meconium plug syndrome
- NEC w/ perforation
- Pyloric stenosis
- Testicular torsion
- Tracheoesophageal fistula (TEF)
- Tumors
- Ulcers
- Vascular rings

Bilious vs. Non-Bilious

Bilious OR Non-Bilious Likely NON-Bilious
- Intestinal atresia
- NEC
- Meconium plug
- Meconium ileus
- Malrotation
- Volvulus
- Hirschsprung Disease		 - Pyloric stenosis
- Intussusception
- Reflux

18.8.1.2 Work-up

  • Imaging: Always start w/ KUB!
    • Ultrasound for anatomic, NEC or intussusception
    • Consider contrast study
      • Upper if concern for malro/volvulus
      • Lower in concern for jejunal/ileal atresia
  • Sepsis eval if concerned for NEC
  • Bowel rest
  • If concerned for surgical diagnosis, consult Surgery
  • Further lab evaluation depending on clinical presentation/suspected etiology: CBCd, chem10, blood gas, lactic acid, LFTs, amylase/lipase, BCx, UA/UCx, stool guaiac, consider metabolic/endocrine work-up

18.8.2 Acute Abdomen in the Neonate

“High” Obstruction “Low” Obstruction “Acquired” Disease
- Esophageal atresia
- Duodenal atriesia
- Duodenal web
- Annular pancreas
- Malrotation
- Jejunal atresia		 - Ileal atresia
- Meconium ileus
- Meconium plug
- Hirchsprung disease
- Anal atresia		 - NEC
- Hypertrophic pyloric stenosis
- Incarcerated inguinal hernia
- Gastroenteritis
- Sepsis
- Perforated stress ulcer
Main symptom: Emesis Main symptom: Constipation
KUB: No distal bowel gas KUB: Dilated small bowel loops (proximal to obstruction) and microcolon (distal to obstruction)

18.8.3 Indirect Hyperbilirubinemia

  • ALL infants: Juandice in the first 24 HOL should ALWAYS be considered pathologic and prompt an immediate serum bilirubin, both total and direct
  • Infants > 35 wks GA: Use BiliTool
  • Premature infants have light level (LL) and exchange transfusion levels based on gestational age (use corrected GA):
Gestational Age (corrected) Phototherapy at TsB Exchange Transfusion at TsB
<28w 0/7 5 11
28w 0/7 to 29w 6/7 6 12
30w 0/7 to 31w 6/7 8 13
32w 0/7 to 33w 6/7 10 15
34w 0/7 to 34w 6/7 12 17
  • Other management if approaching exchange transfusion:
    • Aggressive phototherapy
    • Aggressive hydration (IV + PO)
    • IVIG if Coombs positive
    • Consider steroids
    • Prepare for exchange transfusion (call blood bank)

18.8.4 Neonatal Entercolitis (NEC)

18.8.4.1 Etiology

  • Precise etiology unclear
  • Affects 10% of premature infants, w/ increased incidence at lower gestational age
  • Risk factors: Prematurity, IUGR, preinatal asphyxia, PDA, shock/hypotension, umbilical arterial catheter (UAC), congenital heart disease

18.8.4.2 Clinical Manifestations

  • Abdominal distension/discoloration/redness, feeding intolerance, heme positive stools (may be grossly bloody)
  • Non-specific systemic symptoms, including: lethargy, apnea, temperature instability, unexplained acidosis, hyperglycemia, poor perfusion
  • Lab abnormalities: Hyponatremia, hyperkalemia, metabolic acidosis, leukocytosis or leukopenia, thrombocytopenia

18.8.4.3 Work-up

  • Labs: CBCd, blood culture, electrolytes
  • Imaging: KUB w/ left lateral decub

18.8.4.4 Management

  • Supportive care
  • Place replogle tube for decompression
  • Antibiotics, start IVF/TPN
  • Monitor labs and KUB serially
  • Surgery consult

18.8.5 Malrotation (+/- Mid Gut Volvulus)

18.8.5.1 Etiology

  • Developing bowel fails to undergo usual counterclockwise rotation during 4th-10th wk of embryogenesis
  • Peritoneal bands that usually attach bowel to central body axis are misplaced and compress duodenum, resulting in partial obstruction
  • Volvulus results in intestinal obstruction
  • Superior mesenteric artery may be compressed leading to ischemia

18.8.5.2 Clinical Manifestations

  • Newborn <1mo w/ bilious emesis
  • Associated w/ diaphragmatic hernia, omphalocele, gastroschisis

18.8.5.3 Work-up

  • KUB: Usually unremarkable, may have signs of small bowel obstruction
  • UGI: Abnormal position of duodenal-jejunal junction. Volvulus appears as spirla corkscrew of duodenum.
  • US: May show volvulus in small bowel

18.8.5.4 Management

Emergent surgical intervention

  • Modified Ladd’s Procedure:
    • Division of peritoneal bands around the duodenum
    • Colon placed on the left w/ duodenum on the right, to broaden the mesentery
    • Appendectomy preformed so no confusion w/ future abd pain

18.8.6 Duodenal Atresia

18.8.6.1 Etiology

Embryogenic. 1 in 5,000 live births. 25% have Trisomy 21.

18.8.6.2 Clinical Manifestations

Bilious vomiting hours after birth w/o abdominal distention

18.8.6.3 Work-up

KUB shows double bubble sign (gaseous distension of stomach and proximal duodenum)

18.8.6.4 Management

  • NPO w/ NG suction
  • Surgical consult for duodenoduodenostomy

18.8.7 Jujonoileal Atresia

18.8.7.1 Etiology

  • Mesenteric vascular accident during fetal life
  • 1 in 3,000 live births

18.8.7.2 Clinical Manifestations

Bilious vomiting hours after birth w/ abdominal distension, failure to pass meconium; hyperbilirubinemia

18.8.7.3 Work-up

KUB shows air-fluid levels

18.8.7.4 Management

  • NPO w/ NG suction
  • Surgical consult for resection and anastomosis

18.8.8 Meconium ileus

18.8.8.1 Etiology

5% of newborns with cystic fibrosis, and in 1 per 5,000 to 10,000 live births

18.8.8.2 Clinical Manifestations

Abdominal distension and vomiting hours after birth, failure to pass meconium

18.8.8.3 Work-up

  • KUB shows distension, air fluid levels
  • Contrast enema shows microcolon +/- inpacted meconium pellets

18.8.8.4 Management

  • NPO w/ NG suction
  • Water soluble contrast enema
  • Surgical enterostomy if needed