Prematurity & Neonatology

what is the path of deoxygenated blood in fetal circulation?

-SVC → PD → RA

where in fetal circulation does the deoxygenated & oxygenated blood mix?

-RA → PFO

what is the expected shunting of fetal circulation?

-shunting thru ductus arteriosus or foramen ovale (R→L shunting)

is the blood in the umbilical vein deoxygenated or oxygenated?

-oxygenated

what gestational age is considered preterm?

< 37 weeks

what is the definition of a low birth weight?

< 2500g

what is the definition of a very low birth weight?

< 1500g

what is the definition of an extremely low birth weight?

< 1000g

what is the definition of a late preterm infant?

-34-36 weeks + 6 days

what is the definition of a moderate preterm infant?

-32-33 weeks + 6 days

what is the definition of a very preterm infant?

< 32 weeks

what is the definition of an extremely preterm infant?

< 28 weeks

what are the appropriate next steps after a premature delivery?

-APGAR scores

-clear airway

-dry baby

-clamp cord

-ensure onset of respiration within 30s

why does hypothermia occur in premies?

-rapid heat loss exacerbated by large body surface area & inability to produce sufficient heat

what factors increase premie heat loss?

-higher surface areas

-inability to shiver

-decreased body fat

-poor vasoconstriction

what is the MC cause of premie respiratory distress?

-hyaline membrane disease

what is the MC respiratory disease in premature infants?

-hyaline membrane disease

what causes hyaline membrane disease?

-surfactant deficiency

what is the Tx for hypothermia in infants?

-incubator or heat lamp

how does hyaline membrane disease present?

-resp distress = nasal flaring, retractions, tachypnea

how is hyaline membrane disease diagnosed?

-imaging

• CXR = atelectasis with ground glass appearance & domed diaphragm

what is the Tx for hyaline membrane disease?

-supportive

• ventilator support

-pharm

• exogenous surfactant

what causes bronchopulmonary dysplasia?

-disruption of normal development, injury, or prematurity

how does bronchopulmonary dysplasia present?

-acute resp distress in 1st week

what is the Tx for bronchopulmonary dysplasia?

-supportive

• supplemental O2 or ventilation

-pharm

• glucocorticoids

• diuretics

how is bronchopulmonary dysplasia diagnosed?

-imaging

• CXR = diffuse haziness & coarse interstitial pattern

what is tracheoesophageal atresia?

-lack of continuity of esophagus

tracheoesophageal atresia is often associated with what concurrent defect?

-tracheoesophageal fistula

how does tracheoesophageal atresia with a fistula present?

-copious oral secretions

-aspiration

-resp distress

-inability to pass NG tube into stomach

how is tracheoesophageal atresia diagnosed?

-imaging

• CXR

what is the Tx for tracheoesophageal atresia?

-procedural/surgical

• surgery

how are general respiratory complications in neonates diagnosed?

-imaging

• CXR

• echo

how are respiratory complications in premies prevented & managed?

-decrease preterm birth

-corticosteroid (betamethasone)

-intubation/ventilation

-administer exogenous surfactant

-surgery

what is apnea in a premature infant?

-respiratory pause for > 20s

how does apnea present in infants?

-respiratory pause

-cyanosis

-bradycardia

what is the Tx for apnea in infants?

-methylxanthines (caffeine citrate)

-CPAP

what is intraventricular hemorrhage?

-hemorrhage between thalamus & caudate nucleus that may rupture into ventricles (if large)

how does intraventricular hemorrhage present?

-ASx (grade 1-2)

-hypotension

-metabolic acidosis

-altered neuro status

how is intraventricular hemorrhage diagnosed?

-imaging

• cranial US

what is the Tx for intraventricular hemorrhage?

-supportive

-procedural/surgical

• subgaleal/VP shunt if post-hemorrhagic hydrocephalus

what are key clinical signs of intraventricular hemorrhage?

-H&H drop

-bulging fontanelle

what are possible causes of hypoglycemia?

-diminished glycogen stores → GDM

-diminished glucose production

what is the Tx for hypoglycemia?

-maintenance glucose

-target 50-110

what is retinopathy of prematurity?

-developmental vascular disorders characterized by an incompletely vascularized retina

how does manual ventilation affect retinopathy of prematurity?

-makes it worse

what are the stages of retinopathy of prematurity?

-stage 1: mild abnormal blood vessel growth

-stage 2: moderate abnormal blood vessel growth

-stage 3: severe abnormal blood vessel growth

-stage 4: severe abnormal blood vessel growth + partial retinal detachment

-stage 5: total retinal detachment

what is stage 1 of retinopathy of prematurity?

-mild abnormal blood vessel growth

what is stage 2 of retinopathy of prematurity?

-moderate abnormal blood vessel growth

what is stage 3 of retinopathy of prematurity?

-severe abnormal blood vessel growth

what is stage 4 of retinopathy of prematurity?

-severe abnormal blood vessel growth + partial retinal detachment

what is stage 5 of retinopathy of prematurity?

-total retinal detachment

how does severe retinopathy of prematurity present?

-abnormal eye movements

-crossed eyes

-nearsightedness

-leukocoria

what is the Tx for retinopathy of prematurity?

-pharm

• intravitreal bevacizumab (anti-VEGF)

-procedural/surgical

• laser therapy

low birth weight increases the risk for what neuromuscular condition?

-cerebral palsy

when is the onset of persistent pulmonary HTN of the newborn?

-day 1 of life

how does persistent pulmonary HTN of the newborn present?

-hypoxia refractory to supplemental O2

-respiratory distress

-parenchymal lung disease

what is the hallmark pathophysiologic feature of persistent pulmonary HTN of the newborn?

-R→L shunting thru PDA or PFO

what is the Tx for persistent pulmonary HTN of the newborn?

-supportive

• supplemental O2 &/or iNO

-pharm

• BP support = crystalloid fluids (+/-) pressors

-procedural/surgical

• oscillator

• ECMO

what is neonatal abstinence?

-passive & physiologic addiction to maternal drugs taken during pregnancy

how does neonatal abstinence present?

-jitteriness & tremor

-yawning

-poor sleep

-high-pitched cry

-poor feeding

-seizures

what is the Tx for neonatal abstinence?

-supportive

• low light, quiet environment

• swaddling

-pharm

• morphine

• methadone

• phenobarbital

• *indicated based on Modified Finnegan Abstinence scores

how do you use the Modified Finnegan Abstinence scoring system?

-2 consecutive scores > 12 OR 3 consecutive scores > 8 → Tx indicated

maternal cocaine use increases the risk of what obstetric complications?

-placental abruption

-preterm labor

-poor infant attentiveness

what are the indicates that a premie is ready for discharge?

-medically stable w/o acute illness

-can tolerate enteral nutrition with normal suck & swallow

-can maintain normal body temp

-can breathe regularly w/o apnea or bradycardia