Neonatal Flashcards
Each VS is consistent with the term newborn EXCEPT:
A. HR 140
B. RR 40
C. SBP 90
D. DBP 40
C - SBP 90
What is the neonatal period?
The 1st 28 days of life
What is the infant period?
29 days - 1 year
The VS of a kid older than ____ bear a closer resemblance to the adult than a neonate.
1 year
While neonates are resilient, they have a reduced _________.
Physiologic reserve
What is normal SBP for newborn?
70
What is normal DBP for newborn?
40
What is normal HR for newborn?
140
What is normal RR for newborn?
40-60
What is normal SBP for 1 year old?
95
What is normal DBP for 1 year old?
60
What is normal HR for 1 year old?
120
What is normal RR for 1 year old?
40
What is normal SBP for 3 year old?
100
What is normal DBP for 3 year old?
65
What is normal HR for 3 year old?
100
What is normal RR for 3 year old?
30
What is normal SBP for 12 year old?
110
What is normal DBP for 12 year old?
70
What is normal HR for 12 year old?
80
What is normal RR for 12 year old?
20
Select the statements that MOST accurately reflect the CV system in the newborn. (Select 2).
A. HR is the primary determinant of BP
B. Neo is a 1st line treatment for hypotension
C. Stress is more likely to activate the parasympathetic nervous system
D. Hypotension is defined as SBP <70
A & C
Neonates consume _____ as much O2 and produce ____ as much CO2 than the adult on a weight adjusted basis.
twice; twice
What is the primary determinant of CO and SBP in the neonate?
HR
T/F: Stroke volume fluctuates in the neonate.
False - it is relatively fixed
What is the best way to support BP for the neonate and why?
Increasing HR; the non-compliant LV is sensitive to increased afterload
_______ of the heart is immature at birth, w/ the SNS being less mature than the PNS.
Autonomic regulation
How does the neonate respond to the stress of DL?
With bradycardia
Why does the neonate respond to DL by bradycardia?
Autonomic regulation of the heart is immature at birth, with SNS being less mature than PNS
Why is the neonate predisposed to intracerebral hemorrhage?
HTN, immature cerebral auto-regulatory response, and fragile cerebral vasculature
Neonates have higher or lower oxygen consumption and carbon dioxide production.
Higher
Since O2 consumption and C2O production are twice that of the adult, neonates must increase ___________ accordingly.
alveolar ventilation
Why do neonates have such a high RR?
B/c it is more metabolically efficient ot increase RR than TV to increase alveolar ventilation for increased O2 consumption and C2O production
What is the TV of neonates?
6 mL/kg
The ventricle of the neonate is ______
non-compliant
What CV relationship is underdeveloped in the newborn?
Frank-Starling
What is the formula for BP?
BP = HR x SV x SVR
What is considered hypotension in the newborn?
SBP <60
What is considered hypotension in the 1 year old?
SBP <70
What is considered hypotension for the kid older than 1 year old?
<[70 + (kids age x 2)]
In the setting of hypovolemia and bradycardia, what medication should you administer?
Epinephrine (it is preferred over atropine)
What can you administer prior to induction in the neonates to prevent complication from DL?
Atropine
What reflex normally occurring with hypovolemia is poorly developed in the neonate?
The baroreceptor reflex, this reflex fails to increase HR in the setting of hypovolemia
What is the primary determinant of SBP in the neonate?
HR
What is hypotension for a 5 year old?
<80
What is hypotension for a 2 year old?
<74
Which statement MOST accurately describes the infants airway? (Select 3).
A. Glottic opening is positioned more cephalad
B. Vocal cord position at C1-C2
C. C shaped epiglottis
D. Epiglottis is floppy
E. Right and left mainstem bronchi take off at same angle
F. Vocal cords have anterior slant
A - glottic opening more cephalad
E - R & L mainstem bronchi take off at same angle
F. Vocal cords have anterior slant
Neonates have preferential _____ breathing.
nose
Neonates have preferential nose breathing up to what age?
5 months
Neonates have a ____tongue relative to the volume of the mouth.
larger
Neonates have a shorter or longer neck?
shorter
What shape epiglottis do neonates have?
U or omega shaped
Neonates epiglottis is ____ and ____
longer and stiffer
Neonates vocal cords taken on an ____ slant
anterior
Where is the laryngeal position in neonates?
C3-C4
Where is the narrowest fixed region of the neonate’s airway?
cricoid ring
Where is the narrowest dynamic region of the neonate’s airway?
vocal cords
The shape of the subglottic airway of the neonate is what?
A funnel
The right mainstem bronchus position of the neonate is ____ vertical.
less
The right mainstem bronchus of the neonate takes off at a ____ degree from midline.
55
T/F: The sniffing position is used for the neonate.
False
Where does the glottis reside in the adult?
C5
In the full-term newborn where is the glottis?
C4
A cephalad larynx + larger tongue = _________
acute OA/LA angle
What limits the size of the ETT in the neonate?
Cricoid ring diameter
What may require emergency airway management of the neonate if they are unable to convert to mouth breathing?
Bilateral choanal atreasia
What is the breathing pattern of adults?
Mouth or nose
The tongue of the neonate is closer to the _______. What does this mean?
soft palate; more likely to obstruct upper airway and more difficult to displace during DL
What is the consequence of the infant having a shorter neck when it comes to DL?
More acute angle is required to visualize the glottis
What is the shape of the adult’s epiglottis?
Leaf or C
Does an adult or infant have a floppy epiglottis?
Adult
Where are the vocal cord’s postioned in the adult?
Perpendicular to trachea
Why is it sometimes more difficult to pass the ETT in the infant?
The anterior slant of the vocal cords
The larynx of the infant is more ____,____, ___ BUT NOT ____.
superior, cephalad, rostral
NOT anterior
When is the only time the infant’s airway is more anterior?
during neck flexion
What blade is preferred in the neonate?
Miller
The larynx is located at C____ for the neonate.
C3-C4
The larynx descends to C4 at _____ and achieves the adult position by _____ .
@1 year; 5-6 years old
How can the neonate feed and have spontaneous ventilation?
The larynx is positioned higher in the neck placing the epiglottis in contact with the soft palate
What is Poiseulle’s Law?
Small changes in radius can significantly increase resistance to airflow (radius to the 4th power for laminar flow)
The subglottic airway shape in the adult is ______
cylinder
The subglottic ariway shape in the neonate is _______
funnel
The right mainstem bronchus is more ____ in the adult.
vertical
In the adult, the right bronchus takes off at a _____ degrees and the left at ____ degrees off midline.
25; 45
What is the ideal position for intubation in the neonate?
head on bed with shoulder roll
What are situations that would increase the risk of cricoid edema?
ETT that is too large, multiple ETT attempts, prolonged intubation, frequent head positioning while intubated
During an inhalation induction, a neonate begins to desaturate shortly after the removal of the facemask. Which statement BEST explains why the neonate desaturated so quickly?
A. Decreased TV to dead space ration
B. Oxygen consumption is 3 mL/kg/min
C. Increased alveolar ventilation to FRC ratio
D. Patient has MH
C - increased alveolar ventilation to FRC ratio
Who has the increased oxygen consumption, neonates or adults?
Neonates
Who has the increased alveolar ventilation, neonates or adults?
Neonates
Who has the greater FRC, neonates or adults?
Adults
Why do neonates desat so rapidly?
During hypoventilation or apnea, the neonate’s relatively higher O2 consumption will quickly exhaust the O2 reserve contained in the FRC
Why do neonates have a faster inhalation induction?
There is faster turnover of the FRC allowing for speedier development of anesthetic partial pressure inside the alveoli
The distal saccules of the lung begin to develop alveoli between ________ of gestation.
24-28 weeks
The number of alveoli continue to rise thorughout childhood until ______
8-10 years of age
The neonatal alveolar surface area is only _____ of the adult
1/3
Basal O2 consumption of the neonate is _____ of teh adult
2-3x
What is the O2 consumption of the neonate?
6-9 mL/kg/min
What is the alveolar ventilation rate of the neonate?
130 mL/kg/min
What is teh O2 consumption rate for the adult?
3.5 mL/kg/min
What is the alveolar ventilation rate for the adult?
60 mL/kg/min
What is the FRC of the neonate?
30 mL/kg
What is the FRC of teh adult?
34 mL/kg
T/F: There is an increased turnover of gases in the FRC of the neonate.
True
Why do neonates experience O2 desaturation much faster than adults?
- Increased VO2
- Increased Va to increase O2 supply
- Decreased FRC
When compared to the adult, select the true statements regarding the pulmonary system in the newborn. (Select 2).
A. the diaphragm has more type 1 than type 2 muscle fibers
B. the diaphragm has more type 2 than type 1 muscle fibers.
C. the newborn has a higher TV on a per weight basis
D. neonates have the same amount of dead space on a per weight basis
B & D
What is the primary muscle of inspiration?
diaphragm
Why does the neonate have an increased risk for respiratory fatigue?
A smaller # of type 1, slow-twitch endurance muscle fibers within the diaphragm
Patients <60 weeks post-conceptual age should be admitted for _____ observation with an apnea monitor.
24-hour
In the neonate, what muscles are inadequately developed and contribute very little to ventilation?
intercostal muscles
The ribs of the neonate are more _____. Why is this significant?
horizontal ; they are less able to significantly augment thoracic volume
The diaphragm and intercostal muscles are composed of ___ types of muscle fibers.
2
What are type 1 muscle fibers of respiratory muscles?
Slow-twitch muscle fibers that are built for endurance
Which type muscle fiber is resistant to fatigue?
Type 1
What are type 2 muscle fibers of respiratory muscles?
Fast-twitch msucle fibers that are built for short bursts of heavy work
Which type of muscle fiber tires easliy?
Type 2
The nenoatal diaphragm only has ___% type 1 fibers compared to ____% in the adult.
25%; 55%
What explains the reduction in neonatal ventilatory reserve?
Fewer type 1 fibers
How many type 1 fibers do preterm babies have?
10%
Neonates are at risk of _____ following surgery and anesthesia.
apnea
The risk of apnea in the neonate is inversely related to what?
gestational and post-conceptual age (PCA)
What medication may reduce the risk of post-op apnea after GA in the neonate?
Prophylactic caffeine 10 mg /kg IV
What is the dose of prophylactic caffeine?
10 mg/kg IV
______ is an alternative to caffeine, but has a higher risk of toxicity.
Theophylline
Which muscle fibers are slow tiwtch?
Type1
Which muscle fibers are fast twtich?
type 2
After surgery, pateints less than what post-conceptual age should be admitted for 24-hour observation with an apnea monitor?
60 weeks
When compared to the adult, which statement presents the MOST accurate understanding of neonatal pulmonary mechanics? (Select 2.)
A. Airflow resistance during tidal breathing is decreased
B. Residual volume is decreased
C. Closing capacity is increased
D. Chest wall compliance is increased
C & D
Compared to the adult, the newborn has higher or lower lung compliance?
LOWER
Compared to the adult, the newborn has higher or lower chest wall compliance?
HIGHER
What is paradoxical breathing?
Chest wall collapse during inspiration
Neonates compared to adults:
______ FRC
_______ Vital capacity
______ total lung capcity
_____ residual volume
____ closing capcity
______ tidal volume
Neonates have a
smaller FRC, VC, and TLC
Greater RV and CC
similar TV
When the neonate inspires, it must overcome the ______ and the _____.
resistance to airflow; elastic properties of the chest wall and lungs
The lung volume at end-expiration (where the opposing forces are equal) is called _____.
FRC
What creates the negative pressure in the pleural space of adults?
The chest wall tends to expand and the lungs tend to collapse
Why does the newborn have lower lung compliance?
B/c they have fewer alveoli
WHy does the newborn have higher chest wall compliance?
D/t cartilaginous ribcage that gives less structural supports (it is flimsy)
Why is the newborn predisposed to hypoxemia?
CC overlaps with TV during normal breathing –> V/Q mismatch –> ↑A-a gradient
What 3 processes support the newborn’s effort to dynamically increase the FRC?
- sustained tonic activity of inspiratory muscles
- Narrowing of glottis during expiration
- Shorter expiratory time w/ faster RR creates end-expiratory pressure
What is the FRC of the neonate in mL/kg?
30 mL/kg
What is the VC of the neonate in mL/kg?
35 mL/kg
What is the TLC of the neonate in mL/kg?
63
What is the RV of the neonate in mL/kg?
23 mL/kg
What is the CC of the neonate in mL/kg?
35 mL/kg
CC is ____ in the neonate.
Increased or decreased?
Increased
RV is ____ in the neonate.
Increased or decreased?
Increased
TLC is ____ in the neonate.
Increased or decreased?
decreased
VC is ____ in the neonate.
Increased or decreased?
decreased
FRC is ____ in the neonate.
Increased or decreased?
decreased
Resistance is inversely proportional to _______
the radius⁴
Select the data set that MOST accurately depicts a normal umbilical ABG?
A. pH 7.2; PaO2 50; PaCO2 50
B. pH 7.3; PaO2 20; PaCO2 50
C. pH 7.35; PaO2 30; PaCO2 40
D. pH 7.4; PaO2 90; PaCO2 30
B - pH 7.30; PaO2 20; PaCO2 50
What supplies oxygen to the fetus?
The umbilical vein
What returns CO2 rich blood to the placenta?
Umbilical arteries
How many umbilical veins are there?
1
How many umbilical arteries are there?
2
What does clamping of the umbilical cord stimulate?
The newborn to breathe rhythmically
(An acute rise in PaO2 promotes continous breathing, hypoxemia causes apnea)
The newborn comes into the world with what kind of pH?
Acidotic
What is the pH of a newborn upon delivry?
pH 7.2
How long does it take a newborn’s pH to stablize?
1 hour
1 hour after devliery, a newborn’s pH stabilizes at what?
7.35
Respiratory control doesn’t mature until ______ post-conceptional age.
42-44 weeks
Before th 42-44 weeks post-conceptional age mark, ______ inhibits ventilation.
Hypoxemia
Blood Gas of Mother at term:
pH ______
PaO2 ______
PaCO2 ______-
pH 7.40
PaO2 90 mHg
PaCO2 30 mmHg
pH of the umbilical vein (placenta fetus)?
7.35
pH of the umbilical arteries (fetus placenta)?
7.30
PaO2 mmHg of the umbilical vein (placenta fetus)?
30
PaO2 mmHg of the umbilical arteries (fetus placenta)?
20
PaCO2 mmHg of the umbilical vein (placenta fetus)?
40
PaCO2 mmHg of the umbilical arteries (fetus placenta)?
50
Newborn’s pH 10 minutes after delivery is _______
7.20
Newborn’s pH 1 hour after delivery is _______
7.35
Newborn’s pH 24 hours after delivery is _______
7.35
Newborn’s PaO2 10 minutes after delivery is _______
50
Newborn’s PaO2 1 hour after delivery is _______
60
Newborn’s PaO2 24 hours after delivery is _______
70
Newborn’s PaCO2 10 minutes after delivery is _______
50
Newborn’s PaCO2 1 hour after delivery is _______
30
Newborn’s PaCO2 24 hours after delivery is _______
30
The umbilical ____ supplies oxygen to the fetus
vein
Why is the pH higher in the umbilical vein than in the umbilical arteries?
B/c the umbilical vein supplies O2 to the fetus
The newborn comes into the world _____, ____, and retains ______l
hypoxic, acidotic, and retains CO2
The neonate takes deep breaths to replace ____ with ____ in the alveoli.
fluid with air
(its alveoli contains fluid)
The neonate generates a relatively normal FRC in the first ________
20 minutes
During the 1st hour of extrauterine life, what is the newborn hyperventilates, hypoventilates, or breathes normally?
Hyperventilation
After respiratory control matures at 42-44 weeks post-conceptual age, _____ stimulates ventilation.
Hypoxemia stimulates ventialtion
How does hypoxemia impact ventilation in the newborn?
It depresses ventilation
Compare the PaO2 of the umbilical vein and artery.
Vein: 30
Artery: 20
Compare the pH of the umbilical vein and artery.
Vein: 7.35
Artery: 7.3
What statement regarding fetal hemoglobin is TRUE?
a. it has a higher P50 than the adult
b. it is replaced by Hgb A at 9 months of age
c. it has an increased affinity for 2,3-DPG
d. erythrocytes contain Hgb F have a shorter lifespan
D - erythrocytes containing hemoglobin F have a shorter lifespan
Fetal hemoglobin shifts the curve to the left or right?
Left
Fetal hemoglobin shifts the curve to the left (P50 = ______ mmHg)
19.5
HgbA begins to replace HgbF at ____ of life.
2 months
HgbA has been completely replaced by HgbF by ______ of life
6 months
When does P50 achieve the adult value? And what is this value?
by 6 months; 26.5 mmHg
Fetal hemoglobin (Hgb F) has a P50 of ____
19 mmhg
Hgb F shifts the curve to the _____-
left (love or locked in)
Why does Hgb F benefit the fetus?
It creates an oxygen partial pressure gradient across the uteroplacental membrane that facilitates the passage of O2 from mom to fetus
Adult hemoglobin (Hgb A) consists of ____ and _____ chains
2 alpha; 2 beta
Hgb F consists of 2 ______ and 2 ___ chains.
2 alpha and 2 gamma
Where is the binding site for 2,3- DPG?
Only on the beta chain of Hgb
Since Hgb has 2 gamma chains instead of 2 beta chains, it does not bind ______
2,3-DPG
2,3-DPG causes a ______ shift in the oxyhemoglobin dissociation curve
right
Why is the Hgb F shifts the curve to the left?
It does not bind 2,3-DPG
What is the Hgb of neonate at birth?
17 g/dL
At month 2-3 of the neonate, what is the Hgb?
10 g/dL - physiologic anemia
(RBC w/ Hgb F is being replaced by RBC w/ Hgb A)
At month 4 of life, _____ increases and Hgb concentrations begin to rise.
erythorpoiesis
What is P50 of Hgb A?
26.5 mmHg
What is the purpose of fetal Hgb?
it facilitates the passage of O2 from the mom to fetus
Hgb F is completely replaced by Hgb A by what age?
6 months
Potential complications of mass transfusion in the neonate include all of the following EXCEPT:
a. metabolic acidosis
b. metabolic alkalosis
c. hypocalcemia
d. hypokalemia
D - hypokalemia
FFP is indicated for _____, _____, or ____. It is not indicated for _______.
FFP is indicated for coagulopathy, massive transfusion, or emergent warfarin reversal. It is not indicated for expansion of intravascular volume.
PLT transfusion is recommended for invasive procedures to maintain the PLT count above __________.
50,000 mm
What are complications associated with mass transfusion of neonate?
Alkalosis, hypothermia, hyperglycemia, hypocalcemia, and hyperkalemia
Why can administering RBCs to neonates cause hyperkalemia and cardiac arrest?
When RBCs are stored, the cell membrane becomes dysfunctional, which allows K+ to leak into the supernatant
Why do neonates (<4 months) have a higher RBC transfusion trigger?
They have a high demand for O2 and Hgb F has an increased affinity for O2 (O2 is locked in and is less likely to be released to metabolically active tissues)
Transfusion trigger of <_____ in the neonate <4 months with severe cardiopulmonary disease
13 g/dL
Transfusion trigger of <______ in the neonate <4 months presenting for major surgery or with moderate cardiopulmonary disease
10 g/dL
What is the dose for RBC administration in the neonate <4 months?
10-15 mL/kg
10 mL/kg of RBC will raise Hgb by ______
1-2 g/dL
Hgb A has a ____ affinity for oxygen than Hgb F.
lower
For neonates >4 months of age, RBC transfusion is rarely indicated if Hgb is > _____.
10 g/dL
For neonates > 4 month sof age, RBC is almost always indicated if Hgb < _______ g/dL.
6
In neonates > 4months of age, RBC transfusion should be considered on a need’s basis for Hgb ____ to ____.
6-10
RBC is indicated for neonates >4 months of age if intraoperative blood loss is > _____% blood volume.
15%
What are the 3 indications for FFP transfusion in the neonate?
- Emergency reversal of warfarin
- Correction of coagulopathic bleeding with increased PT or PTT
- Correction of coagulopathic bleeding if >1 blood volume has been replaced and coagulation studies are not easily obtained
What is the dose for FFP for the neonate?
10-20 mL/kg
When is PLT transfusion recommended for the neonate?
For invasive procedures to maintain PLT count above 50,000
What is the PLT dose for neonates if obtained from apheresis?
5 mL/kg
What is the PLT dose for neonates if obtained from pooled PLT concentrate?
1 pack/10 kg
A single apheresis unit of PLT equals _____ pooled PLT concentrates.
6-8
One pooled PLT concentrate will increase serum PLT by _______.
50 x 10^9/L
Why can alkalosis occur with mass transfusion?
d/t citrate metabolism to bicarb in the liver
Why can hypothermia occur w/ mass transfusion?
d/t transfusion of cold blood
Why can hyperglycemia occur w/ mass transfusion?
d/t dextrose additive to stored blood
Why can hypocalcemia occur w/ mass transfusion?
D/t the binding of calcium by citrate
Why can hyperkalemia occur w/ mass transfusion?
d/t administration of older blood
How can you reduce the risk of hyperkalemia and cardiac arrest w/ RBC administration in the neonates?
Administering washed or fresh cells that are less than 7 days old
Why can hyperkalemia occur with the administration of older blood?
When RBC are stored, the cell membrane becomes dysfunctional, which allows K+ to leak into the supernatant
What causes graft-vs-host disease with the administration of RBC? What are the S/S?
Donor leukocytes attack recipient bone marrow; pancytopenia, fever, hepatitis, and diarrhea
How can you prevent graft-vs-host disease?
administer irratdiated blood b/c gamma radiation destroys donor leukocytes
T/F: The ASA Task Force on Blood Component Therapy has universal trigger for RBC transfusion for neonates of Hgb of 7.
False - there is no universal transfusion trigger recommended
What is the transfusion trigger for a 2 month old kid with severe cardiopulmonary disease?
Hgb <13 g/dL
At what age should you follow Transfusion Practice Guidelines of the ASA Task Force on Blood Component Therapy in a healthy child?
4 months and older
What is the dose range of FFP in a 20-kg patient?
200 - 400 mL
(10-20 mL/kg)
What is the dose for pooled pLT in a 7 year old?
1 pack/10 kg
A 3 kg term neonate requires emergency ex-lap for necrotizing enterocolitis. Her pre-op Hct is 50%. What is the max allowable blood loss to maintain a Hct of 40%?
A. 40 mL
B. 55 mL
C. 70 mL
D. 85 mL
B - 55 mL
What is the normal Hgb of a newborn?
14-20
What is the normal Hgb of a 3 month old?
10-14
What is the normal Hgb of a 6-12 month old?
11-15
What is the normal Hgb of an adult female?
12-16
What is the normal Hgb of an adult male?
14-18
What is the normal Hct of a newborn?
45-65%
What is the normal Hct of a 3 month old?
31-41%
What is the normal Hct of a 6-12 month old?
33-42
What is the normal Hct of an adult female?
37-47%
What is the normal Hct of an adult male?
42-50%
What is the estimated blood volume of a premature neonate in mL/kg?
90-100 mL/kg
What is the estimated blood volume of a term neonate in mL/kg?
80-90 mL/kg
What is the estimated blood volume of a infant in mL/kg?
75-80 mL/kg
What is the estimated blood volume of a 1 year old in mL/kg?
70-75 mL/kg
What is the. formula for max allowable blood loss for a neonate?
EBV x (Hct starting - Hct target)/ Hct starting
The newborn’s kidney tends to:
A. excrete sodium
B. reabsorb sodium
C. reabsorb water
D. reabsorb glucose
A - excrete sodium
Compared to the adult, the neonate’s perfusion pressure is increased or decreased?
decreased
Compared to the adult, the neonate’s glomerular filtration rate is increased or decreased?
decreased
Compared to the adult, the neonate’s diluting and concentrating ability is increased or decreased?
decreased
T/F: At birth, the neonatal kidney is mature.
False - it is immature
Why are neonates intolerant of fluid restriction?
They do a poor job conserving water
Neonates do a poor job ______, so they are intolerant of fluid restriction.
conserving water
Why do neonates not do well with fluid overload?
They are unable to excrete large volumes of water
Neonates have high ____ water losses.
insensible
What is the most significant insensible loss for neonates?
Evaporation
The neonate is an oblidate ____ loser in teh first few days of life.
sodium
GFR improves substantially in the first few weeks of life but does not reach adult levels until _______.
8-24 months of age
Renal tubular function continues to improve after birth, but it does not achieve full concentrating ability until ______.
@2 years of age
Why do neonates lose most of their body water through evaporation?
As a direct result of a surface area to body weight ratio that is 4x that of an adult
How does neonate’s skin contribute to evaporation?
It is immature, thinner, and more permeable to water
Besides sodium, the neonate tends to lose _____ in urine.
glucose
Compared ot the adult, what 3 kidney functions are lower in the neonate?
- Renal perfusion pressure
- GFR
- Diluting and concentrating ability
The total body water for a premature neonate is approximately:
A. 65%
B. 75%
C. 85%
D. 95%
C - 85%
Total body water is _______ in the premature newborn and _______ as the child ages.
highest; decreases
TBW is ______- at birth and _____with age.
highest; decreases
ECF is _______- at birth and ________ with age.
highest; decreases
ICF is _______ at birth and ______ with age.
lowest; increases
(neonates are tiny water balloons)
What are signs of dehydration in the neonate?
sunken anterior fontanel, weight loss, lethargy, dry mucus membrans, increased Hct
ECF is made. up of what 2 things?
Plasma volume and interstitial fluid
TBW% of premature = _________
85%
TBW% of neonate = _________
75%
TBW% of child = _________
60%
TBW% of adult = _________
60%
ECF % of premature = _______
60%
ECF % of neonate= _______
40%
ECF % of child = _______
20%
ECF % of adult = _______
20%
ICF% of premature = _______
25%
ICF % of neonate = _______
35%
ICF % of child = _______
40%
ICF % of adult = _______
40%
In the premature and term neonate, is ECF larger or smaller than ICF?
Larger (ECF > ICF)
TBW as a function of weight approximates adult values by ______ age.
1 year
What does a higher ICF (as the child ages) provide?
A volume reserve in times of intravascular volume loss (feer, fasting, diarrhea)
A ____ reduction of weight in the 1st week is normal.
10%
List the 7 signs of dehydration in the newborn.
- sunken anterior fontanel
- weight loss
- irritability or lethargy
- dry mucus membranes
- absence of tears
- decreased skin turgor
- increased Hct
In what age groups is ECF greater than ICF?
Premature and term neonates
Calculate the hourly maintenance rate for a kid who weights 15 - kg.
50 mL (421 rule)
What are the 4 parts of fluid management?
- hourly maintenance
- NPO deficit
- 3rd space loss
- blood loss
Routine use of _______ solutions is not recommended in the neonate.
glucose-containing solutions (unless at risk for hypoglycemia)
The lower limit of normal serum glucose changes _________ after birth.
a few days
If less than 72 hours old, signs of hypoglycemia develop if the serum glucose is _______.
<30-40 mg/dL
If older than 72 hours, signs of hypoglycemia develop if the serum glucose is _______.
<40 mg/dL
What is the 421 rule?
0-10 kg –> 4 mL/kg/hr
10-20 kg –> 2 mL/kg/hr
>20 kg –> 1 mL/kg/hr
What is the shortcut for the 421 rule if the patient is >20 kg?
Patient’s weight in kg + 40
How should you replace the NPO deficit?
1st hour - 50%
2nd hour - 25%
3rd hour - 25%
3rd space loss calculation for minimal surgical trauma = _______- mL/kg/hr
3-4
3rd space loss calculation for moderate surgical trauma = _______- mL/kg/hr
5-6
3rd space loss calculation for major surgical trauma = _______- mL/kg/hr
7-10
As a general rule, 3rd space loss should not be included when?
in the 1st hour of anesthesia
For blood loss, replace with crystalloid at a ______ ratio
3:1
For blood loss, replace with colloids at a _______ ratio
1:1
For blood loss, replace with blood at a _______ ratio
1:1
What are common choices of fluid for neonates?
NS, LR, PLasma-lyte, 5% albumin
What type of infants are at risk for hypoglycemia?
- premature
- <48 hours old
- small for gestational age
- diabetic motehrs
- kids w/ diabetes who receive insulin on the day of surgery
- kids who receive glucose-based parenteral nutrition
T/F: GA masks the signs of hypoglycemia.
True
What is tx for hypoglycemia for kid?
IV 10% dextrose
IF _______ are present, IV 10% dextrose dose should be double for hypoglycemia.
seizures
What is the dose of IV 10% dextrose for hypoglycemia?
2 mL/kg
What is the dose of IV 10% dextrose for hypoglycemia if sezirues are present?
4 mL/kg
What should you give after administering 10% Dextrose for hypoglycemia?
D10 infusion at 8 mg/kg/min
A 2 week old neonate will be expected to demonstrate all of the following except a:
A. increased free fraction of highly protein bound drugs
B. faster circulation time
C. larger Vd for water soluble drugs
D. shorter DOA for lipid-soluble drugs
D - shorter DOA for lipid soluble drugs
In the neonate, CO is higher or lower?
higher
In the neonate, Vd of ________-soluble drugs is higher.
water
In the neonate, plasma protein concentration is ______-
lower
In the neonate, hepatic function is ______-
immature
In the neonate, renal function is _____-
immature
T/F: The BBB in the neonate is immature.
True
MAC for a neonate is higher or lower?
higher
In the newborn, CO is ______ mL/kg/min.
200
Neonates have a ____ percentage of TBW. What does this mean for water-soluble drugs?
higher; need higher dose to achieve plasma concentration
T/F: A drug bound to a plasma protein cannot exert a physiologic effect.
True
What are plasma proteins thought of for drugs in the plasma?
They are though of as storage sites
Before _______ age, there are lower concentrations of albumin and alpha-1-acid glycoprotein.
6 months of age
Why do drugs that are highly protein-bound cause the neonate to have a higher risk of toxicity?
There are lower concentrations of albumin and alpha-1-acid glycoprotein, so drugs that are usually highly protein-bound are instead increased free drug levels
Do neonates have a lower or higher percentage of fat?
lower
Do neonates have a lower or higher percentage of muscle?
lower
Drug biotransofrmation reactions are underdeveloped in the ____ of life.
first month
When are adult values of drug biotransformation reactions reached?
By about 1 year of age
T/F: The neonate cannot conjugate bilirubin.
True
Why can the neonate not conjugate bilirubin?
D/t a reduction in glucuronyl transferase
When is normal GFR achieved?
8-24 months
When is normal tubular function achieved?
2 years of age
What does the immature BBB allow?
the passage of drugs that would otherwise not be able to enter the brain
Why are neonates have a higher sensitivity to sedative-hypnotics?
An immature BBB
A neonate (0-30 days) MAC is ______ than the infant
lower
Premature: MAC Is ______ than the neonate
lower
Infant 1-6 months: MAC is _______ than the adult
higher
Infant 2-3 months: MAC ________-
peaks at its highest level
(MAC Infant 2-3m > Infant1-6 m > neonate > premature)
What is teh MAC of SEVO at 0-6 days old?
3.2%
What is the MAC of sevo at 6 months to 12 years old?
2.5%
Should the dose of a water-soluble drug increase or decrease for a neonate?
Increase - neonates have a greater percentage of TBW, so they require higher doses of water soluble drugs to achieve plasma concentration
Anesthetic considerations for the administration of NMBD in teh neonate include:
A. avoid Succ
B. longer DOA of Succ
C. larger dose of Succ
D. larger dose of Succ and NDNMBD
C - larger dose of Succ
What is the dose of Succ for neonates?
2 mg/kg
What is the DOA of Succ for neonates?
Same as adult (9-13 min?)
Why do neonates require a higher dose of Succ?
D/t combination of increased ECF and normal sensitivity to SUcc
What is the dose of NDNMBD for kids?
Same as adult
What is the FDA black box warning for succ?
Warns of hyperkalemia associated w/ undiagnosed muscular dystrophy in kids under 8 years old
Anytime a kid experiences CA after Succ, ____ should be assumed until proven otherwise. What is the 1st priority?
hyperkalemia; IV Calcium
What 2 NMBD can be administered IM?
Succ and Roc
What objective data suggests a recovery from NMBD?
TOF ratio >90% and a max inspiratory force (MIF) <-25 cm H2O)
What are SUBJECTIVE signs of recovery from NMBD?
grimacing, elbow and hip flexion, adn brining knees to chest
NMBD are highly _____-solbule.
water
B/c NMBD are water soluble, they do not easily pass through ____ and are confined to _____.
lipid membranes; ECF
B/c neonates have a lerger ECF volume, NMBD have a larger what?
Vd
T/F: The neonatal NMJ is mature.
False - it is immature
(NMJ is. more sensitive to ND NMBD and Succ)
What can happen with administration of Succinylchone in kids <5 years of age?
bradycardia or asystole
What can you give to mitigate the bradycardia/asystole response with Succ administration? What dose?
Atropine pretreatment 0.02 mg/kg IV
What is the pretreatment dose of Atropine?
0.02 mg/kg IV
Despite the black box warning, Succinylcholine remains a suitable option for ____ and ______.
RSI and laryngospasm
When is bradycardia or asystole with Succinylcholine adminsitration more likley?
With repeat administration
What is the IM dose for Succ for neonates and infants?
5 mg/kg
What is the IM dose for Succ for older kids?
4 mg /kg
When compared to administration of Succinylcholine into peripheral skeletal muscle, _____ administration via the _____ approach likely has the fastest onset.
intralingual; submental
T/F: Pseudocholinesterase activity is increased in the neonate.
False - it is reduced
Are there active metabolites with Roc? What?
No active metabolites
What is kids dose of Roc?
0.6-1.2 mg/kg
How is Roc metabolized?
Liver
roc has mild vagolytic properties that may cause a small rise in _____
HR
What is the IM dose of Roc in kids <1 year of age?
1 mg/kg
What is the IM dose of Roc in kids > 1 year old?
1.8 mg/kg
What is onset of Roc after IM administration?
3-4 minutes
What is the Vec dose?
0.1-0.15 mg/kg
Does Vec have active metabolites?
Yes - this may increase DOA in peds patients
_______ is considered a long-acting NMB in peds population.
Vecuronium
How is Vec metabolized?
liver
What is Pancuronium dose?
0.1-0.15 mg/kg
How is Pancuronium primarily eliminated?
Kidneys (unlike vec and roc)
What is a S/E of Pancuronium and why?
HTN b/c of its stronger vagolytic effect
What is Atracurium dose in the neonate?
0.5 mg/kg
What is Nimbex dose in the neonate?
0.1 mg/kg
What is the neostigmine dose for neonates?
0.05-0.07 mg/kg
When does neostigmine reach peak effect?
10 min
What is the dose of edrophonium for neonates?
1 mg /kg
When does edrophonium reach peak effect?
2 min
Edrophonium is associated with ____ muscarinic s/e than neostigmine.
less
Why does a neonate require a higher dose of succinylcholine compared to an adult?
Neonates have a larger ECF volume that more than offsets the degree of NMJ immaturity.
How does the DOA of Succinylcholine in a neonate compare ot an adult?
It is similar
Calculate the hourly maintenance fluid requirement for a healthy neonate that weights 2.5 kg.
10 mL/hr
What is the PO2 when fetal hemoglobin is 50% saturated by oxygen?
19
On a weight-adjusted basis, which drug necessitates a higher dose in the neonate than an adult?
A. roc
B. succ
C. vec
D. nimbex
B - succinylcholine
A 1 month old, 4 kg patient is presenting for major surgery. What volume of PRBC is needed to increase Hgb from 8 to 10?
A. 60 mL
B. 30 mL
C. 120 mL
D. 90 mL
A - 60 mL
Which peds patient will require the HIGHEST concentration of Desflurane to produce surgical anesthesia?
A. premature neonate
B. 3 month old
C. 6 month old
D. term neonate
B - 3 month old
What is the oxygen consumption in a 3-kg neonate?
A. 12 mL O2/min
B. 18 mL O2/min
C. 6 mL O2/min
D. 3 mL O2/min
B 18 (6 mL O2/kg/min)
What is the most common congenital defect of the esophagus?
Esophageal atresia
What is the key diagnostic indicator for tracheoesophageal fistula?
Maternal polyhydramnios
How is diagnosis of TEF confirmed?
By the inability to pass a gastric tube into the stomach
What is the most common type of TEF?
Type C (@90%)
TEF may occur as part of the _______ association.
VACTERL
Approximately 20% of neonates with EA have a ________ defect.
significant cardiac
Where should you place the ETT for patients with EA/TEF?
Below the fistula, but above the carina
What can be used to immediately detect a right mainstem intubation?
A precordial stethoscope placed on the left chest
Most kids with esophageal atresia also have what?
Tracheoesophageal fistual
Why is maternal polyhydramnois a key indicator for TED?
esophageal atresia prevents the fetus from swallowing the amniotic fluid
What are symptoms of TEF?
choking, coughing, cyanosis during oral feeding
For Type C TEF, the upper esophagus _____ and the lower esophagus _____.
ends in a blind pouch; communicates with distal trachea
For patient’s with TEF, what should be done in pre-op?
Echo (b/c of 1/5 having significant cardiac defect [ASD, VSD, TOF, aortic coarctation])
If a patient with a TEF has a g-tube, what should you do prior to induction?
Open it to the atmosphere
If ETT is placed too high in patient with TEF, what happens?
respiratory gas is delivered to stomach
In Type E TEF, what is wrong with the esophagus?
Esophagus is complete with a fistual to trachea
In Type D TEF, the upper esophagus _______ and the lower esophagus ________.
is connected to trachea; is connected to trachea (two fistuals, the 2 portions of the esophagus are not connected)
In type A TEF, the upper esophagus ________ and the lower esophagus ______-.
ends in a blind pouch; ends in a blind pouch
IN a type B TEF, the upper esophagus _____, and the lower esophagus ______.
is connected to trachea; ends in a blind ouch
Which lecithin/sphingomyelin ration suggests fetal lung maturity?
A. 0.5
B. 1.0
C. 1.5
D. 2.0
D - 2
What produces surfactant in the fetus?
Type 2 pneumocytes
Type 2 pneumocytes begin producing surfactant between ________- weeks.
22-26 weeks
When does peak production of surfactant occur?
35-36 weeks
What is the pre-delivery treatment for neonates who do not produce enough surfactant?
Maternal steroids to hasten fetal lung maturity
What is the post-delivery treatment for neonates who do not produce enough surfactant?
CPAP, mechanical ventilation, exogenous surfactant
What type of monitoring should be used for noenates who do not produce enough surfactant?
Preductal and postductal oxygen saturation
What is preductal and postductal oxygen saturation monitoring for?
PHTN, right-to-left cardiac shunt, return to fetal circulation via the PDA
Positive pressure ventilation in the patient with poor lung compliance increases _____________.
the risk of pneumothorax
What increases surface tension of the alveoli? And what does this cause?
a thin layer of water that coats the alveoli; alveolar collapse
What is the law of Laplace?
P = 2T/R
The tendency of alveolus to collapse is directly proportional to _________
surface tension
The more surface tension of the alevoi the more or less likely it is to collaspe?
more likley
The tendency of the alveolus to collapse is inversely proportional to _________.
alveolar radius
The smaller the radius of teh alveoli, the more or less likely it is to collapse?
more likely
T/F: The amount of surfactant an alveolus contains is proportional to its size.
False - each alveolus contains the same amount of surfactant
Larger alveoli have a relatively _______ concentration of surfactant.
smaller
Smaller alveoli have a relatively _______ concentration of surfactant.
higher
What keeps alveolar pressures constant and prevents smaller alveoli from collapsing into larger alveoli?
As the radius changes, so does the concentration of surfactant
What steroid can be administered to hasten lung maturity in risk for premature births?
Betamethasone
What are risk factors for RDS? (respiratory distress syndrome)
Low birth weight
low gestational age
barotrauma from PP ventilation
Oxygen toxicity
ETT intubation
maternal diabetes
What are signs of RDS in the neonate?
grunting, tachypnea, intercostal and subcostal retractions, nasal flaring
Steroids will begin to help the fetus in a laboring mother with a preterm fetus after ______.
18 hours
When is the peak effect of steroids given to a laboring mother with a preterm fetus?
48 hours
What can be used to understand the state of fetal lung development?
Amniocentesis
What is the ratio of lecithin to sphingomyelin (L/S ratio)?
It gives a warning about the state of fetal lung by providing the ratio of lecithin (surfactant) to sphingomyelin (surfactant precursor)
L/S ratio >2 suggets _________-
adequate lung development
L/S ration <____ is associated wtih increased risk fo RDS
2
What is a risk of hyperoxia in neonates of prematurity?
Retinopathy of prematurity (ROP)
Whre is a preductal pulse oximeter placed?
RUE
Where is a postductal pulse ox placed?
lower extremity
When using preductal and postductal oxygen saturation monitoring, what suggests PHTN, shunt, and return to fetal circulation via PDA?
difference between the 2 values
__________ hernia allows the abdominal contents to enter the thoracic cavity.
Congenital diaphrgmatic hernia
What is the most common site for CDH? What side?
The foramen of Bochdalek; left side
What are the consequences of CDH?
pulmonary hypoplasia –> poor pulmonary pulmonary vascular development, increased PVR, PHTN, impaired airway development, and airway reactivity
What should you keep PIP for CDH? Why?
<25-30 cmH2O; to minimize barotrauma and risk of pneumothorax
T/F: For CDH you should monitor preductal oxygen saturation in the RUE.
True
CDH surgery is delayed ______ after birth to allow for stabilization of pulmonary, cardiac, and metabolic status.
5-15 days
What special type of ventilation might be required for CDH?
One-lung ventilation with a single lumen ETT advanced into the mainstem bronchi of “good” lung
What are the possible sites of herniation of CDH?
1.The foramen of Bochdalek (posterolateral)
- Foramen of Morgani (parasternal)
- Around the esophagus (paraesophageal)
When is CDH usually diagnosed?
At birth
What are findings of neonate with CDH?
respiratory distress, a scaphoid abdomen (sunken in), barrel chest, cardiac displacement, and fluid-filled GI segments in the thorax
A __________ can warn of increased intra-abdominal pressure in CDH repair.
pulse ox placed on LE
_________ may increase PIP. For CDH, the surgeon can create what to increase the abdominal volume?
Abdominal closure; he can create a temporary ventral hernia
___to____ shunting through the ductus arteriosus leads to hypoxemia and cyanosis
right to left
During CDH, preductal SpO2 should be >_____.
90%
What surgical techniques are used for CDH?
open or thoracic
In a neonate w/ CDH, PIP should be kept below?
<25-30
After diagnosis, how long is CDH repair normally delayed?
5-15 days
List 3 physiologic conditions to avoid in a neonate with CDH.
Hypoxia, acidosis, hypothermia (all increase PVR)
What condition is MOST closely associated with gastroschisis?
A. prematurity
B. Congenital heart disease
C. Beckwith-Weidemann Syndrome
D. Trisomy 21
A - prematurity
_____ and _____ are defects in abdominal wall development.
Omphalocele and gastroschisis
Is omphalocele or gastroschisis more common?
Omphalocele
What conditions are omphalocele associated with?
Trisomy 21
Cardiac defects
Beckwith-Wiedemann Syndrome
Does omphalocele or gastroschisis include a covering over the abdominal viscera?
Omphalocele
Does omphalocele or gastroschisis not inclue a covering over the abdominal viscera?
Gastroschisis
What is gastroschisis associated with?
Prematurity
Which patient is sicker and at higher risk for fluid and heat loss? Gastroschisis or omphalocele?
Gastroschisis
What are the anesthetic considerations for omphalocele and gastroschisis?
Monitoring of thoracic and abdominal pressures, attention to fluid balance, and body temperature
What causes omphalocele?
Failure of gut migration from the yolk sac into the abdomen
What causes gastroschisis?
Occlusion of the omphalomesenteric artery during gestation. The viscera and intestines herniate on the right of the umbilicus. The viscera are exposed to air following delivery –> inflammation and edema of the bowel
Where is the location of defect for an ompalocele?
midline - involves the umbilicus
What organs are involved in an omphalocele?
Bowel and sometimes liver
Is a covering present with an omphalocele?
yes
What is the incidence of omphalocele?
1:5,000
What are co-existing diseases of omphalocele?
trisomoy 21
cardiac defects
Beckwith-Wiedemann Syndrome
Surgery for omphalocele is ____ urgent.
less
What kind of workup is required before omphalocele surgery?
Cardiac workupt
What are the primary closures of ompahloceles and gastroschisis?
Prosthetic silo
May be staged
Where is the location of defect for a gastroschisis?
Off midline - usually right of umbilicus
What organs are involved in gastroschisis?
bowel
Is a covering present with gastroschisis?
No
What is the incidence of gastroschisis?
1:2,000
Surgery for gastroschisis is done within _______ off diagnosis.
24 hours
IVF _____ mL/kg/day for gastroschisis
150-300 mL/kg/day
Gastroschisis is higher risk for ____ and ____ loss.
fluid and heat
What is done right after delivery of a neonate with gastroschisis?
Abdominal contents are placed in a bag (to minimize water and heat loss)
For gastroschisis and omphalocele, if PIP >_____ then surgical closure of the abdomen may require staging.
25-30 cmH2O
Where should you measure SpO2 for gastroschisis and omphalocele?
on the LE to monitor for impaired venous return
(increased abdominal pressure –> decreased venous return –> decreased CO –> decreased systemic perfusion)
What is a late finding in the patient with untreated pyloric stenosis?
A. hyponatermia
B. hyperkalemia
C. metabolic acidosis
D. alklaine urine
C - metabolic acidosis
When does pyloric stenosis occur?
Hypertrophy of the pyloric muscle creates a mechanical obstruction at the gastric outlet
What can be felt for pyloric stenosis? And where?
Olive-shaped mass; just below the xiphoid process
How does an infant with pyloric stenosis present?
With non-bilious projectile vomiting, leading to dehydration w/ hyponatremia, hypokalemia, hypochloremia, and metabolic alkalosis + compensatory respiratory acidosis
T/F: Pyloric stenosis is a surgical emergency.
False - it is a medical emergency
Pyloromyotomy should be postponed until when?
F/E and acid-base status are optimized
What kind of induction should be done on pyloric stenosis?
RSI (full stomach)
The mechanical obstruction caused by pyloric stenosis occurs betwen the _____ and the ______.
stomach and duodenum
When does pyloric stenosis occur?
first 2-12 weeks of life
Is pyloric stenosis more common in males or females?
males
Is pyloric stenosis associated with other congenital issues? Which ones?
it is not
Metabolic alkalosis shifts the oxygen-hemoglobin dissociation curve to the ____
left
What kind of urine does the infant with pyloric stenosis excrete?
alkalotic urine
Why does the infant with pyloric stenosis excrete alkalotic urine?
the kidneys compensate for metabolic alkalosis by increasing bicarbonate excretion
Why does pyloric stenosis eventually result in paradoxical acidification of the urine?
as dehydration continues, the kidneys retaion Na and water under the influence of increased aldosterone; to maintain electroneutrality, the kidneys lose hydrogen to the urine.
If dehydration is not fixed in a infant with pyloric stenosis, what is the late complication that occurs?
Impaired tissue perfusion –> increased lactic acid production (metabolic acidosis)
A child with pyloric stenosis should NOT proceed to the OR until _______.
the patient is adequately volume resusciated; preop f/e and renal labs are normal
Severe dehydration in pyloric stenosis patients should be corrected with ______. When is this done?
20 mL/kg NS; BEFORE surgery
What are the maintenace fluids used in pyloric stenosis surgery?
D5 1/2NS at 1.5 x the rate
Besides decompressing the stomach, what does an oro/nasogastric tube in pyloric stenosis do?
It is used to asses the pylorus for an air leak after surgical repair; an airleak suggests mucosal perforation
What is common post-op pyloric stenosis reapir?Why?
apnea; d/t CSF pH remaining alkalotic even after serum acid-base status is normalized
Excessive vomiting leads to what 5 metabolic abnormailites?
- Dehydration
- Hyponatermia
- Hypokalemia
- Hypochloremia
- Metabolic alkalosis & compensated respiratory acidosis (early)
How does pyloric stenosis impact urinary pH?
Early - alkalotic d/t bicarb excretion
Late - acidic d/t hydrogen excretion
Is pyloric stenosis a medical or surgical emergency?
Medical
In the infant with pyloric stenosis, severe dehydration should be treated with a bolus of:
20 mL/kg NS
What is the MOST appropriate gas mixture for the neonate with necrotizing enterocolitis?
A. 30% O2 + 70% N2O
B. 50% O2 + 50% N2O
C. 50% O2 + 50% air
D. 100% O2
C - 50% O2 and 50% air
What are the risk factors for necrotizing enterocolitis?
Prematurity (<32 weeks) and low birht weight (<1,500 g)
Necrotizing enterocolitis (NEC) is likely the result of _________.
early feeding
(Impaired absorption by the gut –> stasis, bacterial overgrowth, and infection)
With NEC there is an increased risk of what?
bowel perforation
How are babies with NEC managed?
Medically
What is NEC?
Necrosis of the bowel
Where does NEC most commonly occur?
Terminal ileum and proximal colon
What is the diagnosis for NEC?
fixed dilated intestinal loops, pneumatosis intestinalis (gas cysts in bowel), portal vein air, ascites, and free air in abdomen
If bowel perforation occurs in babies with NEC what is done? What can this cause?
Bowel resection and colostomy; short gut syndrome (nutrient malabsorption)
Birth weight of _____ is a risk factor for NEC
<1500 g
What action (if taken too early) can cause NEC in a premature baby?
Early feeding
Select the most significant risk factor for ROP?
A. sepsis
B. prematurity
C. hypoxemia
D. intraventricular hemorrhage
B - prematurity (ROP is retinopathy of prematurity)
ROP causes _________________ in the retina.
abnormal vascular devleopment
The immature retinal blood vessels in infants with ROP are at risk for what?
vasoconstriction and hemorrhage
Dysfunctional healing of ROP creates scars. What do these scars do?
As they retract, they pull on the retina, causing retinal detachment and blindness
What are the 2 most important risk factors for ROP?
prematurity and hyperoxia
Until retinal maturation is complete, supplemental O2 should be minimized to maintain SpO2 ____ - _____.
89-94%
When is retinal maturation complete?
up to 44 weeks after conception
Vasculogenesis occurs ___ and ____ weeks post conception.
16 and 44
Where does the process of vasculogenesis begin?
At the macula and then continues outwards towards the edges of the developing retina over time
What is phase 1 of ROP?
inhibited growth of retinal vessels
What is phase 2 of ROP?
overgrowth of abnormal vessels with fibrous bands that extend to the vitreous gel which can precipitate retinal detachment
What are normal PaO2 values in utero?
20-30 mmHg
What are normal PaO2 values after delivery?
55-85 mmHg
Besides the 2 main risk factors, what are other risk factors for ROP?
mechanical ventilation , blood transfusion, intraventricular hemorrhage, sepsis, vitamine E deficiency
_____ SpO2 is preferred in neonates b/c it better correlates with teh O2 saturation in the retinal vessels.
Preductal (RUE)
What are the surgical options for late-stage ROP?
cryotherapy, laser therapy, scleral buckle, vitrectomy
Based on experimental animal data, which anesthetic agent is LEAST likely to cause apoptosis?
A. Ketamine
B. N2O
C. Precedex
D. Versed
C - Precedex
What is apoptosis?
The process of programmed cell death
What anesthetics are associated with apoptosis?
Halogenated agents, N2O, Propofol, Etomidate, Ketamine, Benzos, and Barbiturates
Bilirubin is a byproduct of _________
RBC breakdown
Any condition that increases serum bilirubin can cause ______ in the neonate
kernicterus (fetal encephalopathy)
Rapid brain growth occurs during the first ______ of life.
3 years
____________ metabolizes bilirubin.
Glucuronyl transferase (phase 2 reaction)
What pathway is not mature at term and leaves the neonate vulnerable to kernicterus during hte first few days of life?
the glucuronyl transferase (phase 2 reaction ) that metabolizes bilirubin
What are risk factors for kernicterus?
Prematurity, low plasma protein concentration, acidosis
What are the treatments for hyperbilirubin?
Phototherapy and exchange transfusion
Which condition is MOST likely to be accompanied by PHTN?
A. omphalocele
B. ROP
C. pyloric stenosis
D. CDH
D - CDH
Anesthetic considerations for pyloric stensosi include: (select 2)
A. delay surgery till F/e are normal
B. RSI
C. Avoid NGT
D. preop cardiac consult
A and B
Which congenital conditions are frequently associated with cardiac co-morbities? (Select 2)
A. Tracheoesophageal fistula
B. Omphalocele
C. NEC
D. Gastroschisis
A and B
Prematurity is a risk factor for which condition? (select 2)
A. TEF
B. NEC
C. Kernicterus
D. CDH
B and C
A child with which congenital condition would receive the GREATEST benefit from awake intubation?
A. gastroschisis
B. TEF
C. ROP
D. NEC
B
Match each shunt w/ its location within the fetal circulation.
Ductus venosus ________________________
Ductus arteriosus _____________________
Foramen Ovale _______________________
Options:
Umbilical vein –> IVC
RA –> LA
Pulm. artery –> descending aorta
Ductus venosus – umbilical vein –> IVC
Foramen ovale – RA –> LA
Ductus arteriosus – Pulm. artery –> descending aorta
What is the organ of respiration in the fetal circulation?
Placenta
Fetal circulation is arranged in _____, while the adult. is______.
parellel; series
____________ shunt occurs across the foramen ovale and ductus arteriosus.
Right-to-left shunting
SVR is low or high in fetal circulation?
LOW
PVR is low or high in fetal circulation?
HIGH
How much pulmonary blood flow is there in the fetal circulation?
Minimal
LA pressure is low or high in fetal circulation?
Left atrial pressure is low
Fetal circulation is ____ dependent.
shunt
The ductus venous bypasses the _____
liver
The foramen ovale bypasses the _____
lungs
The ductus arteriosus bypasses the ______
lungs
What shunts blood from the umbilical vein to the IVC in fetal circulation?
Ductus venous
What shunts blood from teh RA to the LA in fetal circulation?
foramen ovale
What shunts blood from the pulmonary artery to the aorta?
Ductus arteriosus
There is/are ____ umbilical vein(s) that carries _________ blood from the mom to the fetus.
1; oxygenatd
There is/are _____ umbilical artery(s) that carry _____ blood from the fetus to the mom.
2; deoxygenated
Where does gas exchange occur in fetal circulation?
Placenta
What carries oxygenated blood in teh fetal circulation?
Umbilical vein
What carries deoxygenated blood in the fetal circulation?
Umbilical arteries
Right-to-left shunting in fetal circulation occurs across the _____ and ______.
foramen ovale and ductus arteriosus
Why is SVR low in fetal circulation?
The placenta provides a larger, low resistance vascular bed
Why is PVR high in fetal circulatioin?
The lungs are collapsed and filled with fluid, so there is very little pulmonary blood flow
The _____ shunts oxygenated blood past the liver. What does this help accomplish?
ductus venosus; saves O2 to be used to oxygenate the heart and brain
Oxygenated blood (from the ____) and deoxygenated blood (from the lower body) converge in the ____ for fetal circulation.
ductus venosus; IVC
Oxygenated blood from the ductus venosus travels at a _____ velocity than the deoxygenated blood returning from the lower body.
HIGHER
In fetal circulation, higher velocity (oxygenated) blood enters the RA and flows along a flap of tissue called the ______.
Eustachian valve
What does the Eustachian valve do?
Preferentially diverts oxygenated blood across the foramen ovale (RA –> LA)
This blood goes on to perfuse the myocardium and developing brain
In fetal circulation, lower velocity (deoxygenated) blood is preferentially directed to the _____ and _____. From here, it’s shunted across the _____ into the proximal descending aorta (immediately distal to the left subclavian artery).
RV; pulmonary trunk; ductus arteriosus
What occurs with an infant’s first breath?
Breath –> Lung expansion –> ↑____ & ↓_____ –> ___PVR
↑PaO2 & ↓PaCO2 → ↓PVR
When the placenta separates from the uterine wall or the cord is clamped, what happens to SVR?
SVR increases
When transitioning to extrauterine life, ↓PVR + ↑SVR → LA pressure ___ RA pressure →Flap of foramen ovale closing
LA pressure > RA pressure
What triggers the flap of the foramen ovale to close?
LA pressure > RA pressure
What causes the DA to close?
When PVR decreases with first breath, reversal of blood flow through the ductus arteriosus occurs. This exposes the DA to increased PO2 triggering DA closure.
Besides increased oxygen, what else triggers DA closure?
Decreased circulating PGE1 (released from placenta)
A ductus arteriosus that remains open produces a ________ murmur.
continuous systolic and diastolic murmur
What is the purpose of the foramne ovale?
Shunts blood from the RA to LA
What causes functional closure of foramne ovale?
LAP > RAP (umbilical cord clamping –> increased SVR)
When does anatomic closure of foramen ovale occur?
3 days
What is the adult remnant of the foramen ovale?
Fossa ovalis
In ___% of adult population, the foramen ovale is probe patent and can be opened by probing with an instrument.
30%
A patent foramen ovale increases the risk of what?
Paradoxical embolism (embolus travels to brain instead of lungs)
What is. thepurpose of the ductus arteriosus?
Shunts blood from pulmonary trunk to the aorta
What causes functional closure of DA?
SVR > PVR (increased PaO2 & decreased prostaglandins from placenta)
When does anatomic closure of DA occur?
Several weeks via fibrosis
What is the adult remnant of the DA?
Ligamentum arteriosum
What can be used to close PDA in neonate?
Indomethacin (Prostaglandin synthase inhibitor)
WHat can be used to open a PDA?
Prostaglandin E1 (PGE1)
The ligamentum arteriosum plays a key role in _____. How so?
trauma; rapid deceleration tears the ligament resulting in partial or complete aortic dissection
What is the purpose of the ductus venous?
Allows umbilical blood to bypass the liver
What causes anatomic closure of the ductus venous?
umbilical cord clamping
What is the adult remnant of the ductus venosus?
ligamentum venosum
T/F: the ligamentum venosum cannot be reopened.
False
What conditions increase PVR? (select 3)
A. light anesthesia
B. trendelenburg
C. alkalosis
D. NO
E. anemia
F. hypercarbia
A - light anesthesia
B - trendelenburg
F - hypercarbia
The size and direction of the shunt are dependent on 3 factors:
- ratio of PVR to SVR
- pressure gradients between the cardiac chambers or vessels involved
- compliances of the cardiac chambers
What are conditions that increase the PVR?
hypercarbia
hypoxemia
acidosis
hypothermia
What are conditions that decrease PVR?
hypocarbia, adequate oxygenation, alkalosis, NO
What are conditions that increase SVR?
vasoconstrictors
fluid bolus
Increased SNS tone
What are conditions that decrease SVR?
volatiles
propofol
histamine
hemodiultion
_____ occurs when there is an abnormal communication between the pulmonary and systemic circulations.
Shunting
Right to left shunt occurs when ____ is greater than _____.
PVR > SVR
Left to right shunt occurs when ____ is greater than _____.
SVR > PVR
What is the formula for PVR?
PVR = [(mPAP - PAOP)/CO] x 80
What is normal PVR?
150-200 dynes/sec/cm5
Hypercarbia ____ PVR and hypocarbia ___ PVR.
increases; decreases
Hypoxemia ____ PVR; while adequate oxygenation ____ PVR
increases; decreases
Acidosis ___ PVR, while alkalosis ____ PVR
icnreases; decreases
What is collapsed alveolis effect on PVR?
increases PVR
What position is associated with an increased PVR?
trendelenburg
Is hypothermia or hyperthermia associated with. anincreased PVR?
hypothermia
Vasodilators ___ PVR, while vasoconstrictors ___ PVR.
decrease; increase
Light anesthesia and pain ___ PVR
increase
Hemodilution ____ PVR
decrease
What is the formula for SVR?
SVR = [(MAP - CVP)/CO] x 80
What is a normal SVR?
800-1500 dynes/sec/cm
Sepsis ___ SVR
decreases
Anaphylaxis ___ SVR. Why?
decreases; histamine release, vasodilation, capillary leak
Increases or decreases SVR?????
Fluid bolus
increases
Increases or decreases SVR?????
Hemodiultion
Decreases
Which congenital defects are MOST likely to cause hypoxemia? (Select 3)
A. TOF
B. VSD
C. PDA
D. Coartation of aorta
E. Eisenmenger’s syndrome
F. Ebstein’s anomaly
A - TOF
E - Eisenmenger’s
F - Ebstein’s
Is a cyanotic shunt a R→L shunt or a L→R shunt?
R→L
Is a acyanotic shunt a R→L shunt or a L→R shunt?
L→R
Cyanotic shunt or acyanotic shunt????
TOF
Cyanotic
Cyanotic shunt or acyanotic shunt????
Transpotiion of the great arteries
Cyanotic
Cyanotic shunt or acyanotic shunt????
Tricuspid valve abnormality (ebstein’s)
Cyanotic
Cyanotic shunt or acyanotic shunt????
Truncus arteriosus
Cyanotic
Cyanotic shunt or acyanotic shunt????
Total anomalous pulmonary venous connection
Cyanotic
Cyanotic shunt or acyanotic shunt????
VSD
acyanotic
Cyanotic shunt or acyanotic shunt????
ASD
acyanotic
Cyanotic shunt or acyanotic shunt????
PDA
acyanotic
Cyanotic shunt or acyanotic shunt????
Coarctation of. theaorta
acyanotic
What is. the most common left to right shunt?
VSD
A _____ shunt is associated with a slower inhalation induction and a faster IV induction.
right-to-left
A _____ shunt has a negligble effect on the rate of inhalation induction and possibly prolongs the onset of IV induction.
left-to-right shunt
What is Eisenmenger syndrome?
When a left-to-right shunt changes to. a right-to-left shunt secondary to PHTN
A right-to-left shunt is cyanotic or acyanotic?
Cyanotic
In a right-to-left shunt, blood bypasses the _____.
pulmonary circulation
What are the hemodynamic goals for right-to-left shunts?
Maintain SVR
Decrease PVR
How can you decrease PVR?
Hyperoxia, hyperventilation, avoid lung hyperinflation
What is the most common right-to-left shunt?
TOF
What is Ebstein’s anomaly?
Tricuspid valve abnormality
What are the 5 right-to-left cardiac shunts?
Five T’s
1. TOF
2. Transposition of great arteries
3. Tricuspid valve abnormality
4. Truncus arteriosus
5. Total anomalous pulmonary venous connection
Inhalation induction is faster or slower in right-to-left shunts? Why?
Slower; the shunted blood does not pass through the lungs so it does not pick up any volatile; the rate of rise of FA/FI is slowed
The effect of right-to-left shunt on inhalation induction is most profound with ____ soluble agents (such as ___ or ___) and less of an issue with ____ soluble agents (such as _____.
less (N2O and Des); more (Iso)
What is the pathophysiologic effects of left-to-right shunts?
Decreased systemic blood flow (low CO and low BP)
Increased pulmonary blood flow (PHTN or RVH)
For left-to-right shunts, avoid increased _____.
SVR
For left-to-right shunts, avoid decreased ____. How is this accomplaished?
PVR: by avoiding alkalosis, hypocapnia, high FiO2, and vasodilators
What are the 4 left-to-right cardiac shunts?
- VSD
- ASD
- PDA
- Coarctation of the aorta
What are the complications of increased pulmonary blood flow related to left-to-right shunts?
- volume overload of both ventricles
- Ventricular hypertrophy
- Biventricular failure
- Decreased lung compliance + increased airway resistance
- PHTN
Why does Eisenmenger Syndrome occur?
When PHTN occurs in a patient w/ left-to-right shunt, the increased right heart pressures cause a reversal of flow through the cardiac defect –> right-to-left shunt, hypxemia, and cyanosis
During a surgical repair of TOF, the patient’s BP declines by 25% and the SpO2 decreases by 10%. What are the MOST likely explanations for these findings? (Select 2)
A. PVR decreased
B. SVR decreased
C. Myocardial contractility increased
D. Preload increased
B - SVR decreased
C - Myocardial contractility increased
____ is the most common cyanotic congenital herat anomaly.
TOF
What are the 4 defects associated with TOF?
- RV outflow tract obstruction
- RV hypertrophy d/t high-pressure load from obstruction
- VSD d/t septal malalignment
- Overriding aorta that receives blood from both ventricles
A “tet spell” presents as ___ and ____
hypoxemia and cyanosis
What is the best induction agent for TOF?
Ketamine
What medications should be avoided in TOF? (3) Why?
Morphine, Meperidine, Atracurium; Histamine release
With TOF, you should ensure adequate ____ and ____.
preload, SVR
For TOF, prevent increased ____
PVR
Contractility and HR should be _____ in TOF
maintained
For TOF, the degree of ______ strongly correlates with the amount of shunt.
RVOT obstruction
(W/ increased RVOT obstruction, more deoxygenated blood is shunted through VSD and out aorta)
How does the patient with TOF compensate for deoxygenated blood being released into circulation?What is the risk. ofthis?
eryhtropoiesis; polycythemia →risk of CVA and thromboembolism
What precipitates a tet-spell?
increased sympathetic activity (crying, agitation, pain, defecation, fright, or trauma)
In the TOF patient, increased sympathetic activity causes increased myocardial contractility which can cuase ________ of the RVOT.
spasm of the infra-valvular region
(this increases resistance makes blood flow favor the VSD, increasing R-to-L shunt and hypoxemia)
When a tet spell begins, the child will _____ w/ the onset of hypoxemia.
hyperventilate
What position does a kid assume with a tet spell? Explain why.
Squatting; this increases intraabdominal pressure and compresses the abdominal arteries, which increases RV preload, SVR, and blood flow through. the RVOT. Restoring pulmonary blood flow & reducing the magnitude of R-to-L shunt.
How do you treat tet spells peri-operatively?
FiO2 100%
Fluids to expand intravascular volume
Increase SVR w/ Neo to augment the PVR to SVR ratio
Reduce SNS stimulation (deepen anesthetic, BB - esmolol)
Avoid inotropes (can worsen RVOT obstruction)
Avoid excessive airway pressure
Knee-chest position to mimic squatting
What medication should you avoid in TOF tet-spell b/c it can worsen RVOT obstruction?
Inotropes
Goals for TOF:
____ SVR
Avoid ____
Treat with ____
Increased; vasodilation; Neo
Goals for TOF:
______ PVR
Avoid ____
Treat with ____
Decreased
hypercarbia, hypoxia, acidosis, etc.
NO
Goals for TOF:
_______ contractility and HR
Avoid _____
Treat with ____
maintain
SNS stimulation, Ephedrine, Dobutamine, Epi
Esmolol
Goals for TOF:
____ preload
Avoid _____
Treat with ____
increase
dehydration
crystalloid & Albumin 5%
Ketamine _____ mg/kg IV or _____ mg/kg IM is the best induction agent for TOF.
1-2 mg/kg IV
3-4 mg/kg IM
Why is Ketamine the best induction agent for TOF/
It increases SVR and reduces shunting
Why should you avoid morphine, meperidine, and atracurium with TOF?
histamine release that causes vasodilation and reduced SVR
With TOF the heart may look how on CXR?
“Boot-shaped”
RV hypertrophy in TOF may cause _____ deviation
right axis
In TOF, ______ is proportional to the degree of chronic hypoxemia.
polycythemia
Anesthetic Goals for TOF:
Avoid or safe to administer??????
Ephedrine
Avoid
Anesthetic Goals for TOF:
Avoid or safe to administer??????
Hydration
Safe
Anesthetic Goals for TOF:
Avoid or safe to administer??????
Atracurium
Avoid
Anesthetic Goals for TOF:
Avoid or safe to administer??????
Esmolol
Safe
Anesthetic Goals for TOF:
Avoid or safe to administer??????
Vecurnium
Safe
Anesthetic Goals for TOF:
Avoid or safe to administer??????
Phenylephrine
Safe
Anesthetic Goals for TOF:
Avoid or safe to administer??????
Vasodilation
Avoid
Anesthetic Goals for TOF:
Avoid or safe to administer??????
Hypovolemia
Avoid
What narcotics should be avoided in TOF?
Morphine and Meperidine
Why are some patients with TOF polycythemic?
Chronic hypoxemia stimulates incrased RBC production
Failure of the fossa ovalis to close results in what type. of atrial septal defect?
A. primum
B. secundum
C. sinus venosus
D. perimembranous
B - secundum
What is the most common congenital cardiac anomaly in kids?
VSD
A _____ is an abnormal opening in the atrial septum.
ASD
A patent foramen ovale is what type of defect?
ASD
Where is the most common site for ASD?
fossa ovalis
Flow through the ASD is ___ to ___.
left to right (acyanotic)
T/F: The hemodynamic effects of anesthetic agents are not usually well tolerated wtih ASD.
False - they are
Where is the most common site for VSD?
Ventricular septum jsut below the septal leaflet of the tricuspid valve
Flow through VSD is typically ___ to ____.
Left to right (acyanotic)
What is the physiologic consequence of VSD?
Function of. the pressure gradients between the RV and LV, and in turn, these are dependent on PVR and SVR.
With VSD, you should avoid situations that decrease ____ or increase ____ becuase they can incrase shunt flow.
PVR; SVR
A signficant # of VSD close by the time a kid reaches ___. age.
2 years old
What. isthe most common congenital cardiac defect in the adult?
Bicuspid aortic valve
An ASD at teh fossa ovalis is also known as _____ ASD.
ostium secundum
Because the LA and RA are relatively low-pressure systems, the pressure gradient with ASDs is usually ____.
low
With ASDs, patients may remain symptom free for ____
years
What are the eaerly signs of ASD?
poor exercise tolerance, atrial flutter, atrial fib, CHF
With ASD, if pulmonary vascular disease develops (also known as ______ syndrome), the direction of the shunt may _____.
Eisenmenger; reverse (cause right-to-left shunt)
ASDs can cause ____ during Valsalva like maneuvers if ___ > ____.
paraxocial embolism; RAP > LAP
How are many ASDs fixed?
Closed with percutaneous transcatheter device
VSD is associated with what conditions?
Trisomy 13, 18, 21
VACTERL
CHARGE
What happens with a large VSD?
RV and LV pressures equalize, and PVR and SVR determine direction. ofblood flow
PPV increases or decreases PVR?
Increases
Volatile agents increase or decrease SVR?
decrease
How are VSD closed?
with a patch via an open approach
What may be needed post-op VSD repair?
Inotropic support
What is an early symtpom of ASD?
Poor exercise tolerance
What is Eisenmenger syndrome?
Occurs when a patient with a left-to-right shunt develops PHTN. THis cuases a flow reversal through the cardiac defect, ultimately leading to a right-to-left shunt, hypoxemia, and cyanosis
A patient undergoing surgical repair for coarctation of the aorta.Select the best site to monitor arterial BP.
A. right arm
B. right leg
C. left arm
D. left leg
right arm
What is coractation of the aorta?
Narrowing of the thoracic aortic lumen
Where does the narrowing associated with coarctation of aorta typically occur?
Just before or after the ductus arteriosus
(rarely proximal to left subclavian artery)
Obstruction of blood flow at the level of the coarctation of aorta increases _______.
LV afterload
With coarctation of the aorta, SBP is ____ in UE and ____ in LE.
elevated; reduced
Severe obstruction from coarctation of the aorta presents when?
Very early in life
Lower body perfusion in patients with coarctation of the aorta depends on what?
patent ductus arteriosus
What can be given to keep PDA open?
Prostaglandin E1
T/F: Mild to moderate coarctation will rpesent with symptoms by the first year of life.
False - usually go unnoticed for years
_____ coractation of the aorta is less common and usually presents in neonate.
Preductal
____ coarctation of the aorta is more common and usually presents in the adult.
Postductal
What syndrome is strongly associated with coarctation of the aorta?
Turner Syndrome
If the coractation occurs ______, then the SBP in the RUE will be > the SBP in the LUE.
proximal to the left subclavian artery takeoff
What is differential cyanosis and what is it associated with?
Pink, well-perfused upper body + blue, poorly-perfused lower body
Poor blood flow to lower body from severe coarctation of aorta
What is surgery for coractation of aorta?
Often through left thoracotomy + end-to-end anastomosis
What special instrument is used during coarctation of the aorta surgery?
Aotric-cross clamp
What. is a risk of aortic cross clamp? What can be used to reduce this risk?
Paraplegia; cooling to 34-35 C
Patients with mild-moderate coractation of the aorta form collateral paths involving the ___, ___, ___, and/or ____ arteries.
internal thoracic, intercostal, subclavian, scapular
What x-ray finding may be seen on chest x-ray of patient with coarctation of aorta?
rib notching d/t increased vessel diameter
What are indications for surgical repair of coarctation of aorta in the adult?
exercise intolerance, chest pain, HA, LE claudication
The _____ arm (____-ductal) is used to monitor BP in coarctation of aorta.
right; pre
What are 2 cardiac signs of coarctation of the aorta?
- SBP is > in UE than in LE
- Differential cyanosis
The patient scheduled for a Fontan procedure most likely has a diagnosis of:
a. truncus arteriosus
b. ebstein’s anomaly
c. transposition of the great arteries
d. hypoplastic left heart syndrome
Hypoplastic left heart syndrome
What is Ebstein’s anomaly?
A downward displacement of the tricuspid valve, right atrial dilation, and “atrilization” of the RV
What occurs with transposition of the great arteries?
Each great vessel arises from wrong ventricle (RV gives rise to aorta, LV gives rise to pulmonary artery)
Why is transposition of the great arteries a medical emergency?
Circulation occurs in parallel rather than series with. a poorly-oxygenated circuit and a well-oxygenated circuit
_______ is a single-ventricle lesion that is corrected with staged surgical procedures culminating with the Fontan operation.
Hypoplastic left heart syndrome
In hypoplastic left heart syndrome, pulmonary blood flow is a ____ process. what should be avoided?
passive; anything that increases PVR
_____ is characterized by. asingle artery that gives rise to the pulmonary, systemic, and coronary circulations.
Truncus arteriosus
There is usually a ___ defect with truncus arteriosus.
VSD
There is usually a ___ or ___ with Ebstein’s anomaly.
ASD or PFO
What is the most common congenital defect of the tricuspid valve?
Ebstein’s
___ to ___ shunting occurs at the level of the atria with Ebstein’s.
right to left
What might be prolonged with Ebstein’s?Why?
onset of IV drugs; pooling of drugs in large RA
Maintenance of ____ function is critical with Ebstein’s due to risk of ______.
RV; CHF
Why is a common dysrhytmia with Ebstein’s?
SVT
What. is a common post-op complication. in patient’s with Ebstein’s?
RV failure
What is the RV circuit blood flow in transposition of great vessels?
Systemic venous (desatruated) blood –> RV –> aorta –> repeat
What. isthe LV circuit blood flow in transposition of great vessels?
Pulmonary venous blood (well oxygenated) –> LV –> lungs –> repeat
Why is TGA compatible with life in utero?
B/c flow through the ductus arteriosus and foramen ovale allow communication between the 2 circuits
With TGA, survival outside of the womb depends on what?
Mixing of blood through ASD, VSD, or PFO (if none exists, death is imminent)
What is a temporary fix for TGA?
PDA kept open with prostaglandin infusion
What. isthe Rashkind procedure?
It is used to create an interarterial path to allow some oxygenated blood to reach systemic circulation in TGA
What. is the definitive surgical correction for TGA?
Intraatrial baffle and arterial switch procedures
What are the 4 anatomic features of hypoplastic left heart syndrome?
- Hypoplastic LV
- hypoplastic aortic arch
- mitral and aortic stenosis or atresia
- ductal-dependent circulation
When does Norwood Stage 1 (for Hypoplastic left heart syndrome) occur?
neonatal period
When does Norwood Stage 2 (for Hypoplastic left heart syndrome) occur?
3-6 months of age
When does Norwood Stage 3 (for Hypoplastic left heart syndrome) occur?
2-4 years of age
What are. the surgical goals of Norwood stage 1?
Aortic reconstruction -aortic arch now arises from pulmonary trunk. The pulm. arteries are disconnected from pulm trunk are are used to create shunt from subclavia artery or RV
What are. the surgical goals of Norwood stage 2?
Shunt from stage 1 is taken down and a new connection made between SVC and pulm. arteries
What are. the surgical goals of Norwood stage 3?
Conversion. to Fontan circulation - The IVC is connected to pulm. artery with conduit
After Fontan completion, the patient has ____ ventricle(s).
single ventricle that pumps blood into systemic circulation
How does pulmonary blood flow occur after fontan completion?
passively from SVC/IVC to pulm. artery
After Fontant, blood flow to the lungs is completely dependent on _____ during SV. So, _____ is deterimental to pulmonary blood flow.
negative intrathoracic pressure; increased PVR
What type of ventilation should be avoided after Fontan completion?
PPV (b/c it reduced pulmonary blood flow)
What is the preferred ventilation type for patients that have undergone Fontan?
SV
Patients who have undergone Fontan are ____ dependent.
Preload
With Truncus arteriosus, what steals blood from the systemic and coronary circulation?
Decreasing PVR or increasing pulmonary blood flow
Which conditions. areassociated with a prolonged inhalation induction? (select 2)
a. TOF
b. Ebstein’s
c. Coarctation
d. VSD
A and B
right-to-left (cyanotic shunts) prolong the rate of rise of Fa/FI
Which interventions are most likely to cause hemodynamic compromise in a kid who has undergone a fontan procedure? (select 2)
a. ETT with mechanical ventilation
b. preop volume loading
c. inhalation induction with SV
d. permissive hypercarbia
A and D
Select the best induction agent for TOF.
a. Precedex
B. Ketamine
C. Propofol
D. Sevo
B
