Neonatology Flashcards
Major pathophysiology of cause of physiologic nadir of infancy
Fetus’ EPO levels rise, with the highest levels in the final trimester. Erythropoiesis is directly driven by EPO, and as a consequence, a significant portion of the red blood cell mass is produced in the final trimester of pregnancy.
At birth, blood oxygen levels suddenly increase. Renal oxygen tension sensors detect this sudden rise in oxygen levels, and in response, downregulate hypoxia-inducible factors, which in turn, downregulate the production of EPO, resulting in a slowly decreasing hemoglobin for several weeks after birth
- Other causes: shorter lifespan of HbF, iron depletion
When does physiologic nadir of infancy happen and what is the normal Hgb in full term neonates
8-12 weeks
11.0 g/dL
Amniotic Band Syndrome cause and management
Cause: interruption of the normal sequence of development during the third trimester, affects the arms or legs.
Tx: refer to a plastic surgeon for reconstructive surgery.
Contraindications to breastfeeding (maternal infection (5), medication (3) and infant condition (1) )
Untreated Active TB
HIV (in developed countries)
Human T-cell lymphotropic virus tipe I or II
Untreated brucellosis
Ebola
Illicit drug use
Chemotherapy
Radioactive medications
Galactosemia
If neonate has left humeral fracture, what’s the management?
immobilization with elbow in 90 degrees
Management of delivery-related femur fracture
Pavlik harness (optional)
Management of Erb’s palsy
physical therapy
Complications for neonates born to mothers with phenylketonuria
IUGR
microcephaly
Structural cardiac anomalies
Developmental delay
If mother does not have PKU but fetus does, would they have IUGR or other growth restrictions?
NO
Direct hyperbillirubinemia definition in neonate
> 20% of total bilirubin
Direct hyperbillirubinemia and microcephaly
think CMV
Direct hyperbillirubinemia and microcephaly
think CMV
Pathophysiology of physiologic jaundice and when does it happen?
Increased RBC turnover and decreased BUGT activity
Starts 2-4 days after birth, peaks between 4-5 days
If infant has indirect hyperbillirubinemia, is stooling and wetting diapers, mother has A/B or AB blood type, what’s the likely cause?
G6PD
What is hemolytic disease of fetus and newborn?
Maternal Ab against neonate RBC
Usually when neonate have blood type A or B, mother with type O blood
It’s the IgG that crosses placenta and cause hemolysis
usually severe
When does breast milk jaundice occur and what’s the pathophys
7days to 10 weeks
BUGT inhibition
workup of Ischemis perinatal stroke and what artery does it most commonly effect
L MCA
MRI/ head US, echo (congenital heart disease and thrombus in heart)
Coagulation studies:
Protein C activity/ag
Free and total protein S
Fasting homocysteine
Fibrinogen
Plasminogen
Lipoprotein A
Factor VIII
lupus anticoagulant/antiphospholipid Ab
Factor V
Prothrombin
EEG
Mechanism of brachial plexus injury
stretching of nerves
How does transient tachypnea of the newborn happen? (pathophys)
Labor activates Na-K ATPase channels –> clears fluid from alveoli
If infant is born via c- section, this doesnt happen.
Risks for early onset sepsis
Premature birth between 34-36 wks
Post-term >41 weeks
Maternal fever >38
PROM >18h
GBS status
Incidence in hospital EOS
What is a must for newborn discharge?
Newborn Screen
CHD screen (pulse ox)
hearing test
vitals
voided and stooled, nursing
f/u in 48h
Who should not be early discharged (<48h)?
Neonates born to mothers with chronic medical conditions
excessive maternal bleeding
complications from delivery including need for instrument assistance or C-S
CCHD criteria to pass
95%
3 or less difference in RH and foot
Preterm infant born to a febrile mother vaginally through green/brown-stained amniotic fluid, grunting and tachypnic. Likely pathogen?
Listeria
Causes preterm delivery AND green-brown amniotic fluid
Not likely meconium because infant is premature.
Normal vaginal delivery followed by maternal hemorrhage and neonatal pettechiae, low platelet for both <20. Management and cause?
IVIG
Maternal ITP (maternal alloantibodies to both neonate and maternal platelets)
Difference between maternal ITP and neonatal alloimune thrombocytopenia (NAIT)
Maternal ITP: both maternal and neonate PLT are low
NAIT: only infant’s is low (passive transplacental transmission of maternally derived alloantibody to Ag found on paternal and neonatal platelets.
When do you give maternal platelets?
NAIT
How do you workup congenital neonatal syphilis
Neonatal RPR or VDRL (nontreponemal)
FTA-Abs could be falsely positive since mother’s could still be found in infants’
Umbilical granuloma management
Ligate with absorbable sutures
If persistent, get US to rule out urachal anomalies (umbilical polyp, urachal cyst, patent urachal sinus)
Umbilical hernia should spontaneously close by ___
6 years old
Infant with white forelock and delayed passage of meconium. What is the syndrome?
Waardenburg type 4 aka Waardenburg-Shah
Associated with Hirschsprung
Causes of cyanosis
polycythemia (because of 30g/L deoxygenated hb though there is enough oxygen)
benign if peripheral (acrocyanosis), after feeding, after bathing
Neuro, resp, cardiac also ddx
Neonates born to mothers with poorly controlled DM are at risk of ___
cardiomegaly
Heart failure
asymmetric hypertrophy of intraventricular septum (dynamic outlet obstruction like HOCM)–> propranolol if tachycardic, resolves overtime
Pathophys: decreased cardiac output
Malformation sequence
Disruption sequence
Deformation sequence
Association
Malformation sequence: intrinsic to fetus, abnormal tissue development
Disruption sequence: developing fetus experiences event or exposure that alters normal course of development (amniotic band)
Deformation sequence: abnormal mechanical/structural external forces
Association: part of anomalies like VACTERL
Normal prenatal tests and what they do
Nonstress test (NST): normal = 2 episodes of HR >150bpm in 20-min test (normal variation of HR)
Biophysical profile (BPP): 5 items: HR, fetal breathing, movement, tone, amniotic fluid volume (8-10 is normal)
Normal prenatal tests and what they do
Nonstress test (NST): normal = 2 episodes of HR >150bpm in 20-min test (normal variation of HR)
Biophysical profile (BPP): 5 items: HR, fetal breathing, movement, tone, amniotic fluid volume (8-10 is normal)
Appropriate MAP for infant
~GA in first week of birth
What is the biggest factor that influences neonate hematocrit?
gestational age
(Preterm neonates have lower Hct, decreased sensitivity of hepatic sensors to hypoxia and reduced iron stores)
Sx of neonatal abstinence sd
low-grade fever
mild tremor
facial excoriation
Infant not feeding well, no tone, otherwise normal pulm, CV exam. What should be on the differential?
seizure
Inherited disease of metabolism
some characteristics of preterm vs. term infants (breast, movement, respiration, cartilage)
30-34wk: areola flat, no palpable breast bud. Jerky, nonpurposeful movements of extremities, apnea of prematurity, ear cartilage soft with delayed recoil
34-36 weeks: stippled areola with 1-2mm breast bud, jerky movements of arms, periodic breathing, ear cartilage soft with instant recoil
Post term (42wk): cracked skin that’s peeling, hard ear cartilage
Barium enema for hirschsprung
narrowed distal bowel
