Pediatric Anesthesia Pt1.1 Flashcards
Neonatal tidal volume is generally _____ compared to an adult?
unchanged; about 6mL/kg
How does neonatal oxygen consumption compare to an adult?
- Neonate: 6-9mL/kg/min
- Adult: 3.5mL/kg/min
How does neonatal respiratory rate compare to an adult?
- Neonatal: 35 BPM
- Adult: 15 BPM
What would be expected to be seen during DL with a neonatal upper airway?
- large tongue
- superior larynx
- omega-shaped epiglottis
- angled vocal cords
What is the narrowest portion of the trachea in a neonate?
cricoid cartilage is the narrowest portion in neonate
vocal cords are narrowest in an adult
In a neonate, how does the shape of the trachea vary compared to an adult?
Trachea is funnel shaped
seal is typically formed with an uncuffed tube
In a neonate, how does the angle of the right and left mainstem bronchi compare to an adult?
In the neonate, the R and L mainstem bronchi take off at 55º angle
25º/45º in an adult
In a neonate, how does the distance to the carina vary compared to an adult?
In the neonate, the distance to the carina is about 4 cm, in an adult the distance is about 10 cm
A neonates large occiput and short neck can lead to?
intubation positioning issues, making obstruction worse or difficult to get a good view
How does poiseuilles law apply to a neonatal airway?
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
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
- 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
What is characteristic of the neonates central nervous system?
- incomplete myelination (until 3 yr old)
- immature NMJ
- Immature BBB (until 1 yr old)
- rapid brain growth after birth
What spinal level does the conus medullaris (end of spinal cord) end at in a infant compared to an adult?
Neonate: Conus medullaris at L3
Adult: Conus medullaris at L1
What spinal level does the dural sac end at in a infant compared to an adult?
Neonate: Dural sac ends at S3
Adult: Dural sac ends at S1
The open posterior fontanelle closes at ____, while the open anterior fontanelle closes at ____?
- Posterior fontanelle closes ~4months
- Anterior fontanelle closes ~ 2yr old
Bulging cushion-like fontanelles in an infant could indicate what?
High ICP
Sunken Fontanelles could indicate what in a neonate?
Dehydration
What could an immature BBB entail? When does this generally mature?
- many drugs can penetrate the BBB and potentiate CNS effects
- typically immature until 1 year old
GFR typically reaches adult level by what age?
6-12 months old
What is characteristic of the renal system in a neonate?
- kidney is structurally different
- diminished ADH
- immature renal tubules
What issues may arise from immature renal tubules and an immature renal system?
- can affect metabolism/excretion of drugs
- can have decreased glucose reabsorption leading to hypoglycemia
- can also lead to osmotic issues and fluid shifting
How does the GFR compare amongst various pediatric age groups? (premie, full term, 2 yr)
- premie: ~0.55 mL/kg
- full term: ~1.6 mL/kg
- 2 yr: ~2 mL/kg
Glycogen stores do not reach adult levels until _____ which may lead to what?
- 3 weeks old
- May lead to hypoglycemia
How do albumin and alpha-1 acid glycoprotein levels compare to an adult? What does this lead to?
Low levels of albumin and ⍺1AG (binds basic drugs) leading to more free floating drug (and potential toxicity levels)
How are vitamin K levels characterize in a neonate? What issues can this cause?
- 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
How is gastric pH characterized in a neonate?
- alkalotic at birth
- decreases to normal by day 2
What is a significant cause of the increased risk of GERD in neonates?
- Immature ability to coordinate swallowing with respiration
- doesnt mature until 4-5 months
In neonates, the rate of absorption of PO drugs is _____ due to ________?
In neonates, the rate of absorption of PO drugs is slower due to delayed gastric emptying?
Inability to regulate body temperature is largely affected by?
- large body surface area
- lack of subcutaneous tissue
- inability to shiver
How do neonates increase body temperature?
Non-shivering thermogenesis (NST): enhances metabolism of brown fat leading to heat production
Hypothermia can lead to ___, ____, and ____?
Hypothermia can lead to bradycardia, acidosis, and coagulopathies?
anesthesia can further worsen thermoregulation
What type of heat loss makes up the majority of heat loss in neonates? What is this characterized by? How
Radiant Heat Loss: difference in environmental temperature and transfer of heat without contact
What characterizes evaporative heat loss? What can be done to combat this heat loss?
- Vaporization of liquid from body cavities and respiratory tract.
- Remove wet clothing, wipe down, provide humidified air
What characterizes conductive heat loss? What can be done to combat this heat loss?
- Heat loss through direct contact with an object (such as cold table)
- Make sure contact surfaces are warmed (table, blankets, bed…)
What characterizes convective heat loss? What can be done to combat this heat loss?
- Heat loss though the flow of air movement around the body
- control OR room temperature/airflow (~70-80º)
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
- FALSE: shorter duration of action for lipid-soluble drugs
Absorption and distribution of drugs are ____ primarily because of ____?
Absorption and distribution of drugs are increase primarily because of higher cardiac output
What are the primary reasons that elimination is decreased and metabolism is impaired?
- immature kidneys
- underdeveloped CYP-450 pathway
- immature metabolic pathways
What body fluid composition is characterized in a neonate?
- greater total body water
- larger extracellular fluid compartment
- decreased intracellular fluid
Neonates have a _____ volume of distribution for water-soluble drugs like NMBD
larger Vd
Lower fat stores have what effect on lipid-soluble drugs?
longer clinical effect
Lower protein levels has what effect on protein-bound drugs?
more free drug
