class 1

what are teratogens? what are some examples?

• any agent that can harm an embryo or fetus

• due to exposure of teratogenic agents during fetal development, appearance abnormalities or developmental defects can occur

  • very serous when structures are forming

• examples:

  • ETOH, tobacco, marijuana, methamphetamines, infectious agents, physical agents, metabolic agents

what can the teratogen alcohol cause?

fetal alcohol spectrum disorders (FASD) → cause by prenatal alcohol exposure

what can the teratogen recreational drugs cause?

• tobacco → very low birth weight (VLBW)

• marijuana → VLBW, attention defects

• methamphetamines → cardiac defects

• opioid withdrawal → neonatal abstinence syndrome (irritability, seizures, poor feeding, vomit-dehydration, difficult sleep, tachypnea, excoriations (skin abrasion), temp instability)

what can the teratogen infectious agents cause? what are the two infections?

• rubella & cytomegalovirus (CMV)

• can impact the fetus

what are the teratogen physical agents?

radiation

what can the teratogen retinoids cause? what is a med example?

• disrupts liver development

• ex. accutance (acne med) → disformed liver

what can the teratogen antihypertensive drugs cause?

• if BP drops too much after taking med, not enough pressure to push blood into umbilical cord arteries & baby won’t get enough blood for formation

what can the teratogen psych drugs cause?

disrupts brain development

what can the teratogen seizure meds cause? what is an example drug?

• disrupts brain development

• ex. dilantin

what are the 8 problems with prematurity?

• poor thermal regulation → not enough fat to keep them warm

• immature CNS (apnea & bradycardia) → can cause breathing & HR problems

• immature immunity (infection)

• intraventricular hemorrhage (trauma, asphyxia)

• immature cardiopulmonary system

• immature GI system (NEC)

• jaundice → immature liver not processing bilirubin

• glucose instability → b/c very tiny

what is intraventricular hemorrhage (IVH)? what are the s/sx?

• rupture of vessels leads to bleeding around or into ventricles → change depends on amount of bleeding

• s/sx:

  • tense to bulging fontanel

  • twitching, decreased LOC, apnea, seizures,

what are the risk factors for IVH?

• extreme prematurity → vessels are fragile (</=30wk gestation)

• presence of labor (head pushed against pelvic bone)

• birth asphyxia & need for vigorous resuscitation (low O2 often means poor blood flow → resuscitation can cause bp to rise quickly → stress on vessels)

• mechanical ventilation

• sudden change in BP as a result of rapid hypertonic volume expansion (rapid fluid admin → fragile vessels to rupture)

what is the management for IVH?

• respiration support → oxygenation

• regulate fluids & electrolytes

• suppress/control seizures

• OR for drain/shunt placement (fluid drains from brain to abd)

• postop:

  • HOB 30 degrees

  • check head circumference

  • decrease events that increase or decrease cerebral blood flow: pain, hypoxia, rapid volume expansion, excessive stimulation

why do premature newborns have trouble with thermoregulation?

• immature vasculature tone

• disproportional body surface to body weight

• immature, gelatinous skin w/ decreased subcutaneous fat

  • thin skin → increases heat loss & transdermal water loss up to 5x

• decreased fat → poor insulation & heat conversion

who is more likely to have a lower body temp: preterm vs term? what is the body temp?

• preterm is more likely (36.3-36.9)

• term (36.5-37.5)

what can cold stress lead to? what are the 3 methods temp can be maintained by?

• cold stress → hypoxia, metabolic acidosis, hypoglycemia → increases O2 demand & caloric consumption

  • baby tries to make more heat → uses more O2 & caloric demand

• 3 ways: incubator, radiant warming panel, open bassinet with cotton blankets

what are the potential problems in the respiratory system for premature babies?

• surfactant deficiency

• respiratory distress syndrome

• immature neurological control center or immature respiratory system

what is surfactant deficiency? when does surfactant production begin & for full levels?

• not making enough surfactant to keep alveoli open → collapses & hard to breathe

• production begins at 24 wks & full levels of surfactant at 37 wks gestation (anything less than 37wks is premature)

what is respiratory distress syndrome (RDS)? what are the s/sx? if feeding causes increase in O2, what is the tx?

• delayed lung maturation → not ready for gas exchange

• s/sx:

  • increased RR, retractions, crackles, grunting, flaring, cyanosis

• if feeding causes increase in O2 → do parenteral feeds w/ minimum PO to help with GI maturation

what is immature neurological control center= secondary apnea/ immature respiratory system =apnea of prematurity?

• not full formed respiratory system → increased compliance (easily collapses) → poor oxygenation → apnea (not breathing for >20 secs) → increased acidosis & vasoconstriction → blood shunts away from lungs → more apnea & can be accompanied w/ bradycardia

• baby stops breathing for >20 seconds accompanied by bradycardia

what are the tx managements for surfactant deficiency, RDS, apnea of immaturity (6)?

1. intubation & CPAP

• prevents alveoli from collapsing but it can damage wall, so use least amount of pressure

2. oxygen

3. surfactant replacement therapay

4. Extracorpeal membrane oxygenation (ECMO)

5. serial chest xrays

6. continuous monitoring: cardiorespiratory status, pulse ox, BP, ABG

what is necrotizing enterocolitis? what can it lead to?

• most common GI disorder in premature infants & surgical emergency in neonatal period

• inflammatory disease d/t vascular compromise where the portion of the bowel undergoes necrosis

• can lead to short bowel syndrome

explain pathophysio of necrotizing enterocolitis (NEC). how to diagnose?

• decreased blood to intestines → damages of mucosal cells lining intestine → decreased protective lubricating mucus → bowel wall unprotected against proteolytic enzymes → gas forming bacteria invades area → inflammation, abd distention

• dx

  • xray → sausage shaped intestine w/ soapsuds appearance

what are the s/sx of NEC?

• abd distention

• visible bowel loops (can be seen through the skin)

• bloody stool/ heme positive stool

• feeding intolerance (don’t feed or they will vomit and aspirate)

• increased residual (amount of liquid left in stomach)

• ± bilious vomiting

• lethargy (no nutrition for energy)

• apnea, bradycardia, oxygen desaturation

• blood glucose instability (hypoglycemia d/t lack of glucose)

• temp instability (d/t no fuel for body)

what is the management for necrotizing enterocolitis (8)?

1. STOP FEEDINGS

• NPO 24-48 for infants after birth asphyxia

2. aggressive IV fluid/electrolyte replacement

3. ventilation by endotracheal tube (ETT) if in resp failure

4. NG decompression (critical) & early TPN

• break milk is preferred bc of IgA, macrophages, lysozymes

5. broad spectrum abx (ampicillin, gentamycin, clindamycin → combo taken for rest of life bc liver is immature & can’t metabolize other abx)

6. pain control & minimal handling

7. serial abd xrays, frequent labs

8. surgery → if perforation to do resection and anastomosis (surgically connecting)

what are the 3 abx for necrotizing enterocolitis?

ampicillin, gentamycin, clindamycin → combo taken for rest of life bc liver is immature & can’t metabolize other abx)

what are the 4 diseases tested in newborn screening?

• phenylketonuria (PKU)

• congenital hypothyroidism

• galactosemia

• hemoglobin defects (sickle cell disease)

why do we do new born screening? when & how is this screening done?

• screening helps identify newborns who appear health but could be at risk of having conditions w/ severe complications if left untreated (early identification & initiation of tx → prevents complications)

• done before discharge, 1-3 days of life

• heel stick (blood test)

  • poke heel with lancet → place a drop of blood in each piece of testing paper

what is phenylketonuria (PKU)?