Peds Flashcards
2 categories which have highest rate of adverse events during postoperative period
Neonates
Infants <12m
10x increased incidence of morbidity and mortality in neonates compared to older pediatric patients
Ductus Arteriosus connects
pulmonary artery to Aorta
Ductus venosus
Umbilical vein to IVC (bypassing liver)
Foramen Ovale
Right Atrium to Left ATrium
Umbilical arteries (2)
Umbilical vein (1)
Carries deoxygenated blood from fetus back to mother
carries oxygenated blood
Umbilical cord cut and clamped marks the start of ________ . The flow to the ______ is markedly reduced which causes its closure
↑ flow out LVOT, DA senses ↑ pO2, PGE from placenta ↓ & DA closes
transitional circulation
Ductus Venosus
Transitional circulation - System goes from ____PVR to ___ PVR and ___ SVR to ___ SVR
LOW PVR (↓ resistance) to ↑ PVR
High ↑ SVR to Low ↓SVR
Transitional Circulation - What happens in the Lungs?
Amniotic fluid replaced by air; (raising alveolar O2 tension) and fluid is resorbed.
Blood flow to the lungs increases
Hypoxic vasoconstriction in lungs reverses
Transitional Circulation - ↑ blood return to LA which ______
(↑ pressure) causing PFO to close
Hyperoxia and hormonal factors cause ____ to close
DA
Factors that increase PVR, may delay transition from fetal circucation AKA persistent fetal circulation.
Lung disease
pulmonary hypoplasia
Acidosis
Hypoxemia
PpHTN develops a. result of
BPD and Cardiac Disease
Persistant PHTN in the newborn is characterized by:
A sustained elevation of PVR
decreased perfusion to the lungs
DA and FO remain open
Continued R –> Shunt
R and L ventricular dysfunction with diminished CO
Managing PHTN
Nitric
HF ventilation (oscillation)
O2
Surfactant (pre-term)
Maintain Normal HCT - viscous blood triggers vasoconstriction
use of lung recruitment strategies, such as high-frequency ventilation and exogenous surfactant administration, is particularly important in infants with PPHN associated with parenchymal disease, but has limited impact in infants with primary vascular disease
Meds to treat PHTN
PDE-5 inhibitors
Sildenafil; Tadalafil
Meds to treat PHTN
Endothelin Receptor Antagonists:
Bosentan
Meds to treat PHTN :
Prostanoids
Prostacyclin, Treprostinil
when surgery is necessary, all neonates require
____or _____ anesthesia
General or Regional
Postop apnea is a common occurrence in young infants who are ________ and observation for______ is necessary
< 60 weeks’ post-conceptual age
24 hours
fetal circulatory system relies on the ______ for delivery of oxygen and transport of CO2.
The ________ is the functional unit of the placenta
placenta
chorionic villus
Fetal circulation is characterized by high pulmonary vascular resistance
and low systemic circulatory resistance
Uninflated atelectatic lungs and hypoxic vasoconstriction
high flow and low impedance of placental vessels
With the cessation of placental blood flow, aortic pressure ______. Clamping of the umbilical vein ______ SVR. PVR falls with lung expansion, and increasing
PaO2 produces _______ resulting in further decreases in PVR. These changes in systemic and pulmonary blood flow produce corresponding changes in intracardiac pressure.
_____ in RAP with accompanying increases in LAP change the direction of blood flow through the FO, resulting in the ______ of the FO. THE FO may reopen if RAP is > LAP (e.g., pulmonary hypertension),
INCREASES
DOUBLES
pulmonary vasodilation
Decreases, Increases ,
functional closure
Term used to describe permanent closure of the FO within 2-3 months
Anatomical closure
In utero, what maintains the patency of the DA?
prostaglandins
Within a few hours after birth, the muscular wall
of the DA constricts, preventing retrograde blood flow from the ______ into the _______ artery.
Functional closure of the DA aka _________ occurs within ______.
Anatomic closure aka -_________ requires _______
aorta, pulmonary
(thrombosis) , 1 to 8 days
(Fibrosis of the DA), 1 - 4 months
Closure of the DA is precipitated by the increase in SVR and decrease in PVR. Closure of the DA is also influenced by elevations in the systemic PaO2 that occur after birth.
Persistent fetal circulation is common in ______ and infants with ____________,
preterm infants & infants with metabolic derangements
examples of metabolic derrangements:
asphyxia, sepsis, meconium aspiration, CDH
Primary precipitating factors of PPHN
Hypoxemia, Acidosis, Pneumonia, and Hypothermia
Oxygenation, correcting acidosis, and maintenance of normothermia will attenuate the increase in PVR
Accordingly, the neonatal heart is _____ capable of generating a response to an increase in resistive load (increase in stroke volume) and is dependent on _______ for contractility.
Despite this immaturity, the neonatal heart is capable of limited increases in SV up to left atrial pressures of ________mm Hg when afterload remains low.
LESS
free ionized calcium
10-12
neonatal heart is operating near the _____of the Frank-Starling curve because there is
a _________
peak
- limited reserve to increases in both preload and afterload.
pediatric cardiac output is highly
dependent on ________.
Heart Rate
In the s/o bradycardia atropine may be less effective b/c marked increases in heart rate fail to a large extent to produce further increases in _______
This is the more important intervention:
CO
volume expansion (VE)
The combination of hypovolemia and bradycardia produce dramatic decreases in cardiac output that threaten organ perfusion. ________ rather than
atropine increases contractility and heart rate and is warranted for the treatment of bradycardia and decreased CO in pediatric patients.
EPI
The __________ is not completely developed,
limiting the neonate’s ability to compensate for hypotension with the reflex tachycardia as would be expected in the older child and adult
baroreceptor reflex
Autonomic innervation of the neonatal heart is predominantly controlled by the _______
This predominance produces bradycardia that may occur with minor clinical interventions such as
pharyngeal suctioning and laryngoscopy
parasympathetic nervous system.
The ECG axis of a neonate is shifted to the ____ but shifts to the ______ with maturation and accompanying hypertrophy of the left ventricle
Right
Left
Hypotension is defines as:
____ in term neonates
____ in infants 1-12mo
____ in children 1-10
____ in children >10
< 60 mm Hg in term neonates (0 to 28 days)
< 70 mm Hg in infants (1 month to 12 months)
< 70 mm Hg + (2 × age in years) in children 1-10 years
< 90 mm Hg in children >10 years of age
EBV
-Premature
-Newborn (less than 1 month of age)
-Infants 3 months to 3 years of age
-Children older than 6 years of age
-Adults
Premature - 90–100
Newborn (less than 1 month of age) - 80–90
Infants 3 months to 3 years of age - 75–80
Children older than 6 years of age - 65–70
Adults 65–70
Avg HR
Neonate
12 months
3 yr
12 yr
Avg Hr
140
120
100
80
Normal BPs
Neonate
12 months
3 yr
12 yr
70–75 / 40
95 / 65
100 / 70
110 / 60
A decrease in erythropoiesis and decreased life span of the newborn’s red blood cells (RBCs)
produces a progressive decrease in hemoglobin, which peaks approximately between _______
3 and 4 months of age.
The period of “physiologic anemia of infancy” does not compromise the oxygen delivery to tissues, because the oxyhemoglobin dissociation curve shifts to the _____ and RBC concentrations of 2,3-diphosphoglycerate increase
Right
Fetal hemoglobin is replaced by adult hemoglobin during the first _______ producing a rightward shift of the oxyhemoglobin dissociation curve as compared to the neonatal period.
3 to 6 months
Premature infants should receive _______ and ______ Prophylaxis because the concentration of vitamin K–dependent clotting factors _____________ are 20% to 50% of adult levels.
Premature infants have lower levels of vitamin K–dependent clotting factors.
iron and vitamin K prophylaxis,
II, VII, IX, and X
Maternally ingested drugs such as ________ may precipitate the development of a coagulopathy
warfarin and isoniazid
Newborn’s blood volume is dependent on the ________
Delaying umbilical cord clamping in premature infants for ______ stabilizes transitional circulation, decreases the need for inotropic medications and reduces
blood transfusions, necrotizing enterocolitis (NEC), and intraventricular hemorrhage.
time of cord clamping (transfusion from the placenta).
30 seconds