Neonate & Pediatric Development A&P

Question 1

Preterm

Answer 1

before 37 weeks

post-conceptual age

Question 2

Newborn

Answer 2

first 24 hours

Question 3

Neonate

Answer 3

first 30 days

Question 4

infant

Answer 4

1 month to 1 year

Question 5

children

Answer 5

1 to 12 years

Question 6

First trimester

Answer 6

1-12 weeks

Question 7

Second trimester

Answer 7

13-26 weeks

Question 8

Third trimester

Answer 8

27-40 weeks

subcutaneous/muscle tissue development

Question 9

Organogenesis

Answer 9

first 8 weeks

Question 10

Premature

Answer 10

weight < 2,500 grams

Question 11

Preterm neonate

Answer 11

born before 37 weeks

Question 12

Post-term neonate

Answer 12

42 weeks

Question 13

Birthweight ________ by ____ months and ________ by ________.

Answer 13

doubles. …….6

triples. …….1 yr

Question 14

Length ________ by _____ years of age.

Answer 14

doubled…..4

Question 15

Estimation of weight

Answer 15

kg = 2 x Age (yrs) + 9

For > 8 y/o = Age (yrs) x 3

Question 16

Why is weight important?

Answer 16

sensitive index of well being

reflects illness, poor nutrition

Question 17

What occurs with removal of placenta?

Answer 17

SVR increases

Question 18

PVR decreases in neonatal circulation

Answer 18

-major decline to low “adult” levels 2-3 days

Question 19

During 1st week of life, PVR decreases further….

Answer 19

• secondary to remodeling of pulmonary vasculature

- thinning of vascular smooth muscle and recruitment of new vessels

Question 20

Why is resting CO maxed out?

Answer 20

• Fixed SV (decreased myocardial function, stiff heart, less organized)
• Low SVR (pristine vessels)
• Immature SNS to regular BP

Question 21

Range of CO in full-term and preterm neonates

Answer 21

220 to 350 mL/kg per minute

two to threefold greater than adults

Question 22

QRS axis at birth

Answer 22

right sided, reflecting predominant right vent. intrauterine development

Question 23

When does QRS axis shift left?

Answer 23

first month of life as left ventricular muscle hypertrophies

Question 24

Sympathetic nervous sytem

Answer 24

SNS immature

Question 25

What is most important stage in organogenesis?

Answer 25

first 8 weeks gestational

Question 26

Cardiovascular system drive by what?

Answer 26

PNS

• left ventricle is noncompliant and poorly developed
• First 3 months, unable to respond to stress with inotropic support
• limited ability to increase CO even with limited stress

Question 27

Why does LV have limited contractile reserve?

Answer 27

• decreased # of alpha receptors
• increased catecholamines
• limited recruitable SV (decreased myocardial function)
• immature Ca++ transport system
• decreased ventricular conpliance

Question 28

Reason to use Beta agonists to maintain BP

Answer 28

-beta receptors more developed vs. alpha

Dobutamine, isoproterenol

Question 29

Prone to bradycardia

Answer 29

-younger age
-hypoxia
-laryngoscopy
-pain
(PNS driven)

Question 30

Mean heart rate BPM by age

Answer 30

premature: 120-170
0-3 mos: 100-150
3-6 mos: 90-120 
6-12 mos: 80-120
1-3 yrs: 70-110
3-6 yrs: 65-110
6-12 yrs: 60-95
>12 yrs: 55-85

Question 31

Depend on _________ to breath

Answer 31

diaphragm

Question 32

Hypoxia in infants

Answer 32

depresses hypercapnic ventilatory response in infants

normally responses to increased CO2

Question 33

Chest wall compliance

Answer 33

Increased

• underdeveloped intercostal muscles
• small chest cavity
• high diaphragm

Question 34

Airway and alveoli development

Answer 34

develop until age 8

Question 35

Surfactant function

Answer 35

abolish alveoli wall tension

Question 36

What decreases surfactant production?

Answer 36

• premature

- maternal diabetes

Question 37

What occurs with reduced surfactant?

Answer 37

Respiratory Distress Syndrome (RDS)