Lecture 2: Perinatal Care Flashcards
When is a comprehensive newborn assessment to be completed?
Within 24 hours after birth
What is a pre-term baby?
Born prior to 36 weeks and 7 days.
What is a late-term/near-term baby range?
34 weeks - 36 6/7 weeks
What is a term baby range?
37 weeks - 41 weeks 7 days.
What is a post-term baby range?
Greater than 42 weeks
What are we worried about in a late-term/near-term baby?
- Hypoglycemia
- Jaundice
- Respiratory distress
- Temp instability
- Feeding challenges
- Increased readmission
How do we monitor a late-term baby?
- 48 hrs of obs
- Passing carseat test
What is considered SGA birthweight, LGA, and AGA?
- SGA: Less than 10th percentile
- LGA: Greater than 90th percentile
- AGA: 10-90th percentile
GA = gestational age
What is the primary cause of FGR/IUGR?
FGR = fetal growth restriction, IU = intrauterine
Early first-trimester insults like chromosomal or congenital abnormalities, resulting in global growth delay
What characterizes asymmetrical FGR?
Uteroplacental insufficiency or malnutrition that often occurs later, such as 2nd-3rd trimester, causing growth delays due to blood redistribution
What are LGA neonates most at risk for?
Birth trauma, such as brachial plexus inj, clavicle fx, or scalp hematomas
Image of fetal lung physiology
Image of Fetal Circulation
- PDA
- PFO
- Ductus Venosus
Image of fetal lung adaptation at end of gestation
- Increased surfactant production
- Production of fetal lung fluid
Image of stimuli that result in respiratory adaptation
- Thermal stimulation
- Exposure to light & sound
- Tactile stimulation via contractions
Image of CV adaptation
- Increased O2 in blood
- Increased blood flow in lungs
- Increased venous return to LA
- LA pressure increase closes PFO
- O2 constricts ductus arteriosus
Image of CV adaptation Part 2 (Shunt closure)
- Umbilical vein and ductus venosus close
- Increased SVR & O2
- Shunts all close
What does crying do for a newborn fetus?
- Lung expansion and protect lung volume
- Change to rhythmic breathing pattern
What muscles are primary in actual ventilation for a newborn? Quiet breathing?
- Ventilation: diaphragm + intercostals + accessory + abdominal
- Quiet breathing: Diaphragm only
What does clamping of the umbilical cord do?
- Ceases low-resistance circuit in placenta
- Increases systemic BP and relaxing lung vessels
How does fetal life pulmonary circulation differ from live?
- High pulmonary vascular resistance
- Low blood flow
- Most blood is just shunting via ductus arteriosus from the right side of the heart straight to the aorta
When is intubation recommended for a newborn?
Only if concerned for airway obstruction after PPV
What is the preferred site for IV meds for a fetus?
Umbilical vein
What are the 3 considerations to take into concern immediately at birth?
- Is it term?
- What is the tone? (extremity flexion)
- Breathing or crying
Yes to all = no resuscitation
Why is skin to skin preferable for a newborn?
Golden hour!
- Temp regulation
- Trigger mother to produce milk
What 5 steps should we take if 1 of the 3 birth considerations is not met?
- Cut cord and take to warmer
- Stabilize by warming, drying, position airway, clear secretions
- Tactile stimulation during drying
- If bulb suction needed, clear mouth before nose
- Start APGAR clock
What is the resuscitation protocol for a newborn with labored breathing/cyanosis?
- Position and clear airway
- Place spo2 monitor on RIGHT hand/wrist
- Provide supplemental O2 PRN
- Consider CPAP
When is PPV indicated via BVM for a newborn?
Apnea/gasping & HR < 100 BPM
How fast do we ventilate a newborn via BVM?
40-60 breaths per minute
What mnemonic should we keep in mind if PPV does not appear to be working during newborn resuscitation?
- Mask adjustment
- Reposition
- Suction
- Open mouth
- Pressure increase
- Airway change
MR SOPA
When are compressions recommended for newborn resus?
HR < 60 BPM despite 30s of PPV
What is the CPR ratio for newborn resus? (Compressions to breaths)
3:1, 3 compressions per breath for 30 inflations and 90 compressions
Use thumbs to depress sternum
What medication should be considered for a newborn remaining under 60 BPM?
IV Epi @ 1:10,000 concentration via venous or ET tube
If we have bagged a newborn, given epi, and it is still not responding well, what should we consider?
- Hypoglycemia (D10W infusion)
- Hypovolemia (NS or PRBCs)
- Pneumothorax
After how much time should we consider ceasing attempts at newborn resuscitation?
20 minutes
When can PPV be discontinued during resuscitation?
- HR > 100 BPM
- Spontaneous respirations
If a newborn >= 36 weeks received resuscitation, what should we examine for?
Signs of HIE (Hypoxic ischemic encephalopathy) or therapeutic hypothermia
What are the risk factors for respiratory distress in a newborn?
- C-section deliveries
- Decreased gestational age
- Low wt
- Male
- Maternal asthma or gestational diabetes
What are the two factors that result in an increased work of breathing for a newborn?
- Decreased lung compliance
- Increased airway resistance
What is TTN? (Transient tachypnea of the newborn)
- Normal resp is 30-60 bpm
- Correlated with increased C-sections
- Delayed resorption of lung fluid leading to pulmonary edema
What might be seen on CXR for a newborn with TTN?
- Hyperexpansion
- Perihilar densities with fissure fluid
- Pleural effusions
When does TTN present?
First 2 hours, lasting up to 72 hours but typically resolving within 12-24 hrs.
How do we manage TTN?
Supportive care, self-limiting
DO NOT USE LASIX!
Lasix is CI due to wt loss and hyponatremia.
What is meconium aspiration syndrome? (MAS)
- Fetal sterile intestinal fluid that will eventually become its first stool.
- Respiratory distress
- Hypoxia
- Trigger: Uterine stress during delivery
What is the diagnostic criteria for MAS?
- Meconium present in amniotic fluid or trachea during intubation
- CXR: Bilateral fluffy densities with hyperinflation
What is the progression of MAS?
- Meconium aspiration
- Inflammation/obstruction/surfactant inactivation
- Atelectasis
- Rupture of alveoli
- V/Q mismatches
How do we manage MAS?
- Dry, warm, stimulate
- O2 for HR < 100 or CPR for HR < 60
- NOT RECOMMENDED TO INTUBATE
What is the leading respiratory disorder for pre-term infants?
Respiratory distress syndrome (RDS)
Lower age = higher risk
What is pathognomonic for RDS?
Ground-glass appearance on CXR
Differentiates from TTN, which is pulm edema
How do we manage RDS?
- Early pre-term infants can be given glucocorticoids and postnatal surfactant
- For current RDS: ventilation, NCPAP, or NIPPV helps if hypoxemic
What is the underlying etiology for persistent pulmonary HTN in a newborn? (PPHN)
Pulmonary vascular resistance remaining abnormally elevated post birth
What is the main concern with PPHN?
Right to Left shunt causing severe hypoxemia that is RESISTANT to conventional respiratory support
What age range is PPHN MC in?
GA > 34 weeks
What 3 respiratory diagnoses are associated with PPHN?
- MAS
- PNA
- RDS
What prenatal factors are associated with PPHN?
- Intrauterine/perinatal asphyxia
- In utero exposure of SSRIs during 2nd half of pregnancy
What are the 3 underlying mechanisms within PPHN?
- Vasoconstriction 2/2 perinatal hypoxia related to an acute event (Sepsis/asphyxia)
- Prenatal increase in pulmonary vascular smooth muscle development (MAS)
- Lung hypoplasia (Diaphragmatic hernia)
All due to V/Q mismatch
How does PPHN typically present?
- Within 24 hrs
- Signs of respiratory distress
- Meconium staining of nails/skin
- Harsh systolic murmur at lower left sternal border (maybe)
What diagnostic is confirmatory for PPHN?
Echo showing normal anatomy with Pulmonary HTN
How is PPHN managed?
- Lowering pulmonary arterial pressure
- Supportive
- Severe: Use of NO or sildenafil
- ECMO last resort
What is the target BGL for 0-4 hrs and 4-24 hrs for a newborn?
- 0-4: BGL > 40mg/dl
- 4-24: BGL > 45 mg/dl
Why does BGL drop in the first 2 hours of life?
Physiological hypoglycemia as placental nutrition depletes.
When do we treat neonatal hypoglycemia? (NH)
When they have actual S/S
What are the risk factors for NH?
- Diabetic mother
- LGA
- SGA
- Late pre-term
- Maternal exposure to labetalol or terbutaline (bronchodilator)
- Genetic syndromes (Turner, Beckwith-Wiedemann, glycogen storage diseases, galactosemia)
What are the high-risk symptoms for NH?
- High pitched cry
- Cyanosis
- Floppiness
- Exaggerated Moro reflex
- Lethargy
- Seizures
- Jitteriness
- Abnormal feeding
- Irritability
- Apnea
What warrants a screening for NH despite being asymptomatic?
- Pre-term or late pre-term (< 37wk)
- LGA or SGA
- Diabetic mothers (including gestational)
Glucose protocol for IV glucose
Just know that symptoms require IV tx. If low BGL, just refeed and check.
What is neonatal jaundice?
- Physiologic: Unconjugated hyperbilirubinemia typically occurring 24hrs post birth, peaking at 3-4d and lasting 1wk.
- If it presents within first 24 hrs PATHOLOGIC
What are the risk factors for hyperbilirubinemia at birth?
- Lower gestational age
- Jaundice within first 24 hrs
- Predischarge bilirubin close to phototherapy threshold
- Hemolysis
- High rate of bilirubin rise (> 0.3/h in first 24h or > .2/h after 24h)
- Phototherapy needed prior to discharge
- Parent/sibling with same
- G6PD deficiency
- Breastfeeding wtih suboptimal intake
- Scalp hematoma or significant bruising
- Trisomy 21
- Macrosomic infant of diabetic mother (LGA baby)
What are the risk factors for neurotoxicity due to hyperbilirubinemia in a newborn?
- GA < 38 wks
- Albumin < 3g/dl
- Isoimmune hemolytic disease, G6PD or other hemolytic diseases
- Sepsis
- Instability in previous 24h
How do we diagnose hyperbilirubinemia?
Jaundice with TcB within 3mg/dl of phototherapy threshold or TcB >=15 with a secondary TSB check
Transcutaneous bilirubin = TcB
Total serum bilirubin = TSB
What is considered a significant conjugated/direct bilirubin level?
Conjugated > 1 with TSB < 5 or if conjugated is > 1/5 of TSB
What additional tests should be considered for high bilirubin?
- ALP
- albumin
- TORCH serology
- CMV urine
- Cultures
- Fasting abd US for biliary atresia or choledochal cyst
- Galactosemia test
- Metabolic tests
What is breastfeeding jaundice and tx?
- First week post birth due to poor feeding
- Intestinal hypomotility or poor elimination of bilirubin in stool
- TX: supplements and formula
Not enough breast milk
Bfeeding = bad feeding
What is breast milk jaundice and tx?
- Post 1st week of birth and lasts up to 3 wks
- Inhibition of UGT and deconjugation of conjugated bilirubin
- Neonates will still have good wt and good feeding
- Tx: Do not withhold breast milk
Getting enough breastmilk but its messing with bilirubin
B milk = bad milk
What is the main concern with phototherapy?
Neurotoxicity risk factors.
If they are present, the TSB threshold goes down.
What is the most important first intervention for infants with jaundice?
Feeding
If a baby is admitted for phototherapy, what intervention is generally not recommended?
IV fluids
Images of phases of neonatal acute bilirubin neurotoxicity
When can we D/C phototherapy for hyperbilirubinemia?
TSB < 2 mg/dl below the hour-specific threshold
What are the risk factors for rebound hyperbilirubinemia?
- GA < 38 wkspreterm
- < 48hrs old at start of phototherapy
- Hemolytic disease
How is G6PD inherited?
X-linked recessive
What is isoimmune hemolytic disease mainly due to?
ABO incompatibility due to maternal antibodies transferring placentally.
Mother has O but baby is A or B.
MC in first child only.
What combination will result in Rh incompatibility?
- Rh+ father
- Rh- mother
What is the main lab that suggests polycythemia for a newborn?
Venous Hct > 65% at term
What is the main consequence of polycythemia in a newborn?
Hyperviscosity of blood, resulting in decreased perfusion of the capillary beds.
Venous thromboses are also common.
What is the main etiology of benign neonatal polycythemia?
Delayed cord clamping
What clinical findings are seen in benign neonatal polycythemia?
- CNS: irritability, jittery, seizures, lethargy
- Cardio: respiratory distress, CHF, PPH (postpartum hemorrhage)
- GI: emesis, heme-positive stool, distension
- Renal: Decrease output, rena vein thrombosis
- Metabolic: Hypoglycemia
- Heme: Hyperbilirubinemia, thrombocytopenia
How do we screen for benign neonatal polycythemia?
Heelstick, but if >68%, do venous after.
When and how do we treat benign neonatal polycythemia?
- Symptomatic = treat
- Isovolemic partial exchange transfusion with NS to dilute blood
- DO NOT TREAT ASYMPTOMATIC
What are the routine newborn tests?
- Metabolic testing
- Newborn hearing
- Critical congenital heart diseases (CCHD)
What are the 3 main conditions that may occur with congenital metabolic disorders?
- Acidosis
- Hyperammonemia
- Hypoglycemia
When should we consider inborn errors in infants?
- Rapid deterioration in otherwise well infants
- Emesis, poor feeding
- Tachypnea, apnea
- Irritability, Lethargy, seizures
- Sepsis with a lack of fever
What are the specific labs that may be indicated in newborn testing?
- Plasma amino acids
- Urine organic acids (Most sensitive in catabolic states)
What are the two possible mechanisms behind inborn errors in infants?
- Defects in metabolism of energy
- Dysfunction of cellular pathways
If an infant presents with lethargy, what are the 4 top DDx to consider?
- Inborn error of metabolism
- Sepsis
- Non accidental trauma
- Congenital Heart Disease
What is Phenylketonuria/PKU?
- Amino acidopathy
- Deficiency in PAH (phenylalanine hydroxylase)
- Converts phe to tyrosine
What is the consequence of untreated PKU and how is it treated?
- Consequence: Accumulation of phe and phenylketones leading to permanent brain injury.
- TX: Lifelong restriction of phe by eating phe-free proteins.
How is Acute PKU treated?
- CABs (Compressions, airway, breathing)
- Stop all protein intake
- IV fluid resus
- D10 IVF to promote anabolic state (avoid hypotonic fluids)
- If due to MSUD, consider hemodialysis for elevated ammonia
glucose fluids have protein-sparing effect
Maple syrup urine disease
How does galactosemia present?
- Metabolic decompensation when an infant gets formula with lactose in it.
- Liver dysfunction, jaundice, and coagulopathy
- E. coli sepsis and cataracts
How is galactosemia treated?
Lifelong dietary restriction of galactose
How does neonatal hypothyroidism tend to present?
- Diffusely enlarged, symmetrical goiter
- Very rarely: myxedema or jaundice
What is the usual cause of neonatal hypothyroidism?
If there is a clinically apparent goiter, its usually an inborn error of thyroid hormone metabolism
When might we consider adding FT3 to a thyroid test for a newborn?
If TSH and FT4 are both normal.
Why do we check TRAbs (thyroid receptor antibodies) in newborns?
A negative test suggests an inborn error or excess maternal iodine.
In a newborn with euthyroid state but goiters present, what test might we do?
US for each goiter if labs present euthyroid.
When is neonatal hearing screening indicated?
- Prior to 1 month and rescreening within 3 if abnormal.
- If NICU pt, any stay > 5d or readmission for hyperbilirubinemia.
Overview of Gastroschisis
- Protruding abdominal organs without a protective sac, almost always to the right of umbilicus
- RFs: teratogens, bad care, young mom
- 4-8% mortality
Lower mortality than omphalocele since its displaced to the side?
Overview of omphalocele
- Protrduing abdominal organs with a protective sac (O cause its in a bubble)
- Usually associated with genetic anomaly/syndrome in 1/2 of cases.
- Goes straight through umbilicus
- 20% mortality
What might suggest a fetus will have an omphalocele/gastroschisis?
- Elevated AFP in the mother’s blood, since only fetus can make.
- viewable with U/S
What are the MCC of elevated AFP?
- Dating errors
- Underestimating gestational age
- Multiple gestation
- NTD
- Abd defects
Define esophageal atresia and presentation
- Blind esophageal pouch that does not connect with esophagus/airway or connects both the esophagus and airway later.
- Baby will be choking, coughing, cyanosis
- Hx of polyhydramnios
Not connected to stomach ultimately.
Tx of esophageal atresia
- Acutely: suction, elevate head, IV glucose
- Definitive: Make a fistula to connect esophagus
MC type of GI obstruction
Bowel atresias
Intestinal obstructions are the MC surgical emergency in neonates
How does an upper/proximal intestinal obstruction present in neonate? Lower/distal?
- Proximal: Emesis after birth
- Distal: Abd distension, late emesis, late/no stooling
What are the two MC types of intestinal atresia?
- Duodenal: down syndrome (D&D)
- Jejunoileal: CF
Clinical Presentation is the same i guess
Common RFs for intestinal atresias
- Smoking
- Preemie
XR sign of duodenal atresia
Duodenal = down + double
XR sign of jejunal atresia
Jejunal = CF + triple
RFs for NTD
- Inadequate folic acid
- Maternal DM
- Maternal Hyperthemia
- VPA exposure
Overview of ancephaly
- Missing part of your brain and skull
- Can’t control swallowing
- Infant will die within hours to days.
Image of spina bifida and subtypes
- Spina bifida occulta: tuft of hair
- Meningocele: Protrusion of only meninges
- Myelomeningocele: Protrusion of meninges + spinal cord
Dx and tx of NTDs?
- Elevated AFP
- U/S
- Extremely Elevated AChesterase in amniotic fluid can confirm
- Spina bifida occulta has normal AFP
- Post birth: MRI to confirm extent
- Tx: C-section + surgery to close the celes early.
- 4 mg of folic acid QD
Define kernicterus
Encephalopathy due to hyperbilirubinemia
The consequence of untreated jaundice
What is the greatest predictor of severe hyperbilirubinemia in an infant?
The strongest predictor of developing progressive to severe hyperbilirubinemia is the newborn’s predischarge total serum or plasma bilirubin (TSB) or transcutaneous bilirubin (TcB) level, which is typically measured at 24 to 48 hours after birth [10,11].