Pediatric Anesthesia Pt1.1

Question 1

Neonatal tidal volume is generally _____ compared to an adult?

Answer 1

unchanged; about 6mL/kg

Question 2

How does neonatal oxygen consumption compare to an adult?

Answer 2

• Neonate: 6-9mL/kg/min
• Adult: 3.5mL/kg/min

Question 3

How does neonatal respiratory rate compare to an adult?

Answer 3

• Neonatal: 35 BPM
• Adult: 15 BPM

Question 4

What would be expected to be seen during DL with a neonatal upper airway?

Answer 4

• large tongue
• superior larynx
• omega-shaped epiglottis
• angled vocal cords

Question 5

What is the narrowest portion of the trachea in a neonate?

Answer 5

cricoid cartilage is the narrowest portion in neonate

vocal cords are narrowest in an adult

Question 6

In a neonate, how does the shape of the trachea vary compared to an adult?

Answer 6

Trachea is funnel shaped

seal is typically formed with an uncuffed tube

Question 7

In a neonate, how does the angle of the right and left mainstem bronchi compare to an adult?

Answer 7

In the neonate, the R and L mainstem bronchi take off at 55º angle

25º/45º in an adult

Question 8

In a neonate, how does the distance to the carina vary compared to an adult?

Answer 8

In the neonate, the distance to the carina is about 4 cm, in an adult the distance is about 10 cm

Question 9

A neonates large occiput and short neck can lead to?

Answer 9

intubation positioning issues, making obstruction worse or difficult to get a good view

Question 10

How does poiseuilles law apply to a neonatal airway?

Answer 10

Infant tracheal lumen is smaller (~4mm diameter) meaning circumferential edema with have a larger impact on airflow

adult tracheal lumen is about 8mm, and less impact by slight circumferential edema

Question 11

Which statement most accurately describes the infants airway? (select 3):

• larynx is positioned more cephalad
• vocal cord position at C4-C5
• narrowest part of the airway is vocal cords
• epiglottis is broad
• right and left mainstem bronchi take off at same angle
• vocal cords have anterior slant

Answer 11

• larynx is positioned more cephalad
• right and left mainstem bronchi take off at same angle
• vocal cords have anterior slant

vocal cords position at C3-C4, narrowest part of airway is cricoid cartilage, epiglottis is omega-shaped

Question 12

What is characteristic of the neonates central nervous system?

Answer 12

• incomplete myelination (until 3 yr old)
• immature NMJ
• Immature BBB (until 1 yr old)
• rapid brain growth after birth

Question 13

What spinal level does the conus medullaris (end of spinal cord) end at in a infant compared to an adult?

Answer 13

Neonate: Conus medullaris at L3
Adult: Conus medullaris at L1

Question 14

What spinal level does the dural sac end at in a infant compared to an adult?

Answer 14

Neonate: Dural sac ends at S3
Adult: Dural sac ends at S1

Question 15

The open posterior fontanelle closes at ____, while the open anterior fontanelle closes at ____?

Answer 15

• Posterior fontanelle closes ~4months
• Anterior fontanelle closes ~ 2yr old

Question 16

Bulging cushion-like fontanelles in an infant could indicate what?

Answer 16

High ICP

Question 17

Sunken Fontanelles could indicate what in a neonate?

Answer 17

Dehydration

Question 18

What could an immature BBB entail? When does this generally mature?

Answer 18

• many drugs can penetrate the BBB and potentiate CNS effects
• typically immature until 1 year old

Question 19

GFR typically reaches adult level by what age?

Answer 19

6-12 months old

Question 20

What is characteristic of the renal system in a neonate?

Answer 20

• kidney is structurally different
• diminished ADH
• immature renal tubules

Question 21

What issues may arise from immature renal tubules and an immature renal system?

Answer 21

• can affect metabolism/excretion of drugs
• can have decreased glucose reabsorption leading to hypoglycemia
• can also lead to osmotic issues and fluid shifting

Question 22

How does the GFR compare amongst various pediatric age groups? (premie, full term, 2 yr)

Answer 22

• premie: ~0.55 mL/kg
• full term: ~1.6 mL/kg
• 2 yr: ~2 mL/kg

Question 23

Glycogen stores do not reach adult levels until _____ which may lead to what?

Answer 23

• 3 weeks old
• May lead to hypoglycemia

Question 24

How do albumin and alpha-1 acid glycoprotein levels compare to an adult? What does this lead to?

Answer 24

Low levels of albumin and ⍺1AG (binds basic drugs) leading to more free floating drug (and potential toxicity levels)

Question 25

How are vitamin K levels characterize in a neonate? What issues can this cause?

Answer 25

* have very little vitamin K which is needed to synthesize clotting factors 2, 7, 9, 10 (1972) and can lead to bleeding *usually give Vit K at birth*

Question 26

How is gastric pH characterized in a neonate?

Answer 26

* alkalotic at birth * decreases to normal by day 2

Question 27

What is a significant cause of the increased risk of GERD in neonates?

Answer 27

* Immature ability to coordinate swallowing with respiration * doesnt mature until 4-5 months

Question 28

In neonates, the rate of absorption of PO drugs is _____ due to ________?

Answer 28

In neonates, the rate of absorption of PO drugs is **slower** due to **delayed gastric emptying**?

Question 29

Inability to regulate body temperature is largely affected by?

Answer 29

* large body surface area * lack of subcutaneous tissue * inability to shiver

Question 30

How do neonates increase body temperature?

Answer 30

Non-shivering thermogenesis (NST): enhances metabolism of brown fat leading to heat production

Question 31

Hypothermia can lead to ___, ____, and ____?

Answer 31

Hypothermia can lead to **bradycardia, acidosis, and coagulopathies**? *anesthesia can further worsen thermoregulation*

Question 32

What type of heat loss makes up the majority of heat loss in neonates? What is this characterized by? How

Answer 32

Radiant Heat Loss: difference in environmental temperature and transfer of heat without contact

Question 33

What characterizes evaporative heat loss? What can be done to combat this heat loss?

Answer 33

* Vaporization of liquid from body cavities and respiratory tract. * Remove wet clothing, wipe down, provide humidified air

Question 34

What characterizes conductive heat loss? What can be done to combat this heat loss?

Answer 34

* Heat loss through direct contact with an object (such as cold table) * Make sure contact surfaces are warmed (table, blankets, bed...)

Question 35

What characterizes convective heat loss? What can be done to combat this heat loss?

Answer 35

* Heat loss though the flow of air movement around the body * control OR room temperature/airflow (~70-80º)

Question 36

A 2 week old neonate will be expected to demonstrate the following **except**? * increased free fraction of highly protein-bound drugs * faster circulation time * larger volume of distribution for water-soluble drugs * shorter duration of action for lipid-soluble drugs

Answer 36

* FALSE: shorter duration of action for lipid-soluble drugs

Question 37

Absorption and distribution of drugs are ____ primarily because of ____?

Answer 37

Absorption and distribution of drugs are **increase** primarily because of **higher cardiac output**

Question 38

What are the primary reasons that elimination is decreased and metabolism is impaired?

Answer 38

* immature kidneys * underdeveloped CYP-450 pathway * immature metabolic pathways

Question 39

What body fluid composition is characterized in a neonate?

Answer 39

* greater total body water * larger extracellular fluid compartment * decreased intracellular fluid

Question 40

Neonates have a _____ volume of distribution for water-soluble drugs like NMBD

Answer 40

larger Vd

Question 41

Lower fat stores have what effect on lipid-soluble drugs?

Answer 41

longer clinical effect

Question 42

Lower protein levels has what effect on protein-bound drugs?

Answer 42

more free drug