Prodigy- Neonatal Anesthesia Flashcards
Approximately what % of oxygenated blood from the placenta is shunted to the IVC and RA via the ductus venosus
35-50%
Blood in the left atrium of the fetus has an o2 sat of what?
65-70%
*the highest seen in fetal ciruclation
is pulm vascular resistance high or low in the fetus
extremely high
due to alveolar collapse and compression of blood vessels and the low PaO2 and pH of the blood entering the pulmonary system
Because of the high PAP in the fetus, approximately 90% of blood is shunted where?
into the descending aorta via the ductus arteriosus
What do the neonatal cardiac myocytes relay primarily on?
the diffusion of calcium through the sarcolema
T/F- sympathetic innervation reaches maturity by early infancy
True
before that, parasympathetic innervation to the heart is dominate
T/F- the SV is fixed in the neonate
true- CO is dependent on HR
During neonatal transition to extrauterine ciruclation, there is a(n) increase/decrease in pulm vasc resistance and a increase/decrease in pulmonary blood flow
significant decrease in PVR
marked increase in pulmonary blood flow
Normal tidal volume of an infant
~ 6-8ml/kg (same as an adult)
will an infant have a faster or slower inhalational induction than an adult- why or why not
why do they desat faster?
faster inhaltional induction
-FRC same + minute ventilation double
^ same
T/F Periodic breathing (clusters of respirations followed by periods of apnea that last 5-10 seconds) are common in the neonate
True
*can last thrhough the first year of life
Baby has a gamma subunit instead of epislon at the NMJ; what significance does this have? (In terms of how it opens)
the NMJ channel is open for a longer period of time, allowing more sodium to enter the cell
→ increased sensitivity to ACH
→increased sensitivty to NDMRs
T/F- infants have increased sensitivity to ACH
what about NDMRs
true
same
Neuromuscular transmission normally reaches maturity by what age?
2 months
prior to this, reserves of ACH in the NMJ are decresed, which can be observed with performing tetanic stimulation
At term, the GFR of a neonate is only about what % of the normal adult rate?
30%
GFR = 3 letters, 30%
why might you want to use cistatracurium in an infant <1 yo?
bc GFR doesn’t mature until infant is about 1yo so using drugs that arent dependent on kidneys for excretion and useful
avoid PCN and gent - or use cautioiuslly
Primary means of maintaining body heat in the neonate
non-shivering thermogenesis
*norepi-mediated mechanism
Infant heat loss occurs (rank from highest to lowest):
evaporation, radiation, conduction, convection
- radiation
- convection
- evaporation
- conduction
3 main changes in body composition in the neonate that affect the pharmacokinetics/dynamics of drugs
- increase total body water
- decrease body fat
- decrease muscle
Weight-based loading doses for (water/lipid) soluable drugs are higher for infants to achieve the same target concentration in the bloodstream
3 examples
water-soluble
dig, aminoglycosides, sux
because of the neonates lower muscle mass, drugs whose termination of action depdends on redistribution into the muscle tissue may have a (higher/lower) initial peak plasma concentration and (shorter/longer) DOA
higher initial peak and longer DOA
Why do neonates exhibit a greater propensity for the development of methemoglobinemia?
due to decreased levels of methemoglobin reductase
Doses of fentanyl between what dose range have been associated with chest wall rigidity, resulting in the need for mechanical ventilation to treat hypoventilation
1-2mcg/kg
onset and duration of IM sux
2 mins onset
DOA 20 mins
How does Vecuronium differ in the neonate?
in the adult it’s considered intermediate-acting
in the neonate, it’s considering to be long-acting bc its hepatic metabolism is limited by immature hepatic function in the neonates (+active metabolites of VOH3 or something)
Low birth weight
Very low birth weight
Extremetly low birth weight (ELBW)
Low birth weight→ <2500g
Very low birth weight→ <1500g
Extremetly low birth weight (ELBW) → < 1000g
Which requires placement of a smaller ETT: subglottic stenosis, tracheal stenosis, both, or neither
subglottic stenosis
*narrowing of the airway BELOW the vocal cords and above the trachea at the level of the cricoid
*tracheal stenosis does NOT necessitate a smaller ETT but airway resistance is increased distal to the ETT
with tracheal stenosis, is airway resistance increased distal or proximale to the ETT
distal