Blood Gases & Hypothermia: Topic 3 Flashcards Preview

Congenital Defects & Pediatrics > Blood Gases & Hypothermia: Topic 3 > Flashcards

Flashcards in Blood Gases & Hypothermia: Topic 3 Deck (107)
Loading flashcards...
1

What do the major differences between adult and pediatric CPB stem from?

Anatomic Differences
Metabolic differences
Physiologic Differences

2

Myocytes/Myofibrils in Peds

Increase in size

3

Number of Mitochondria in Peds

Increases as the oxygen requirements of the heart rises

4

Amt of Sarcoplasmic Reticulum in Peds

Amount of Sarcoplasmic reticulum and its ability to sequester calcium increase in early development

5

Activity of Na+/K+ Adenosine Triphosphate (ATPase) in Peds

Increases with maturation and affects the sodium-calcium exchange

6

What happens when kids don't have adequate pulmonary blood flow?

Won't grow (also blue babies....)

7

What structure is response for SR storing calcium? (Affects ability to release too)

Terminal Cisternae

8

Ca++ handling in the immature myocardium _________(increases/decreases) intracellular Ca++ concentrations post ischemia/reperfusion.

Increases

9

What does an increase in intracellular calcium concentration activate?

Energy-consuming processes --> decreased levels of ATPase--> lack of energy sources for cardiac function--> dysfunction observed after CPB

10

What leads to cellular damage after CPB?

Abnormal and uncontrolled activation of these enzymes

11

What is the pediatric increase in myocardial oxygen demands attributed to?

Associated with a switch from anaerobic metabolism after birth to a more aerobic metabolism

12

Immature myocardium uses what substrates?

Carbs
Glucose
Medium and long chain fatty acids
Ketones
Amino acids

13

What is considered the "mature" heart?

3-12 months

14

What are the primary substrates in the mature heart?

Long-chain fatty acids

15

What happens when the long-chain fatty acids become primary substrates in the mature heart?

Enzymes and an increased number of mitochondria are needed

16

Why can the immature heart withstand ischemic injury better than adult myocardium?

Because of the increased ability of the immature myocardium to rely on anaerobic glycolysis

17

What are premature infants prone to?

Hypocalcemia

18

What can hypocalcemia result in?

Hypoxia, infection, stress, diabetes

19

What are the effects of hemodilution in neonates?

Decreased plasma proteins, coagulation factors and Hgb
Reduction increases organ edema, coagulopathy and transfusion requirements

20

Infants/neonates have a ______ (high/low) oxygen-consumption rate

High

21

What flow rates to infants/neonates require?

200 ml/kg/min at normal temperature (kg based flow rates)

22

What are unique anatomic and physiologic findings in patients with congenital cardiac disease?

Intra-cardiac and extra-cardiac shunts and the reactive pulmonary vasculature

23

How does glucose management on CPB differ between adults/pediatrics?

Adults: control high blood sugar
Peds: control low blood sugar

24

Why do peds get hypoglycemia?

Decrease in glycogen stores

25

Why do adults get hyperglycemia?

CPB --> stress response --> hyperglycemia

26

How does hematologic management differ between adults and pediatrics?

Adults: Inflammatory response
Pediatrics: exaggerated response; inflammatory response inversely proportional to age

27

What is the relationship between inflammatory response and age?

Inversely proportion; younger children have a higher inflammatory response

28

What are the events that trigger stress?

Ischemia
Hypothermia
Anesthesia
Surgery

29

CPB causes hormone release and also releases what?

Catecholamines
Cortisol
ACTH
TSH
Endorphins

30

Cardiac Differences btw adults and peds

Adult: Less ischemia tolerance, potentially preconditioned to ischemia, more tolerant of overfilling

Pediatrics: tolerate ischemia, higher lactates seen, prone to stretch injury