OB lecture

Question 1

Neonate age

Answer 1

1-28 days

Question 2

Infant age

Answer 2

28 days- 1 year

Question 3

Child age group

Answer 3

> 1

Question 4

Minimum hgb of pedis

Answer 4

10
Some say 15

Question 5

Fetal lung development

Answer 5

4 weeks- lung buds
16 weeks- branching of bronchial tree into 28 divisions
24w- immature alveoli, surfactant, t2 cells, survivable with artificial ventilation
28 30 weeks- capillary network
36-40 weeks- true alveoli present, 20 million
birth - 3 mo- pao2 rises, shunts close
6 y- 350 mil alveoli

Question 6

What stimulates first breathe

Answer 6

clamping of umbilical chord
low fetal o2 for continuous breathing

Question 7

spo2 at 1 hr ph

Answer 7

.95 28
7.36

Question 8

pressure required for peds to inflate lungs

Answer 8

-70cm h2o

Question 9

What is the primary event of the respiratory system transition

Answer 9

Initiation of ventilation

Question 10

How can u maintain frc/ lung inflation up until 6yo during anesthesia

Answer 10

5 peep

Question 11

How long can peds fight hypoxia

Answer 11

2 minutes

Question 12

What abolishes hyperneic response to hypoxia

Answer 12

low levels of anesthesia
hypothermia

Question 13

What abolishes the neonates response to co2

Answer 13

hypoxia

Question 14

Hypoxia causes profound ___ in babies

Answer 14

profound brady

Question 15

Define apnea in infants

Answer 15

respiratory pauses of 20 seconds OR
Pauses with brady or cyanosis

Question 16

O2 consumption in peds

Answer 16

Increased 6ml/kg

Question 17

Why and how soon does the ductus arteriosis close?

Answer 17

constricts within minutes from increased PO2, and decreased prostaglandins, physiologic closure 10-15 hr, anatomic closure 2-3 weeks

Question 18

Hypoxia and acidosis consequences

Answer 18

increased pvr
p htn
RAP> LAP
Open a foramen ovale

Question 19

S&S P htn in the newborn

Answer 19

marked cyanosis
acidosis
tachypnea
shunts FO and DA

Question 20

PPHTN tx

Answer 20

hyperventilation
Pulmonary vasodilators- pg
Minimal handling
Avoiding stress
Adequate ventilation and oxygenatino

Question 21

When are all nephrons developed?

Answer 21

34 weeks

Question 22

Neonate renal characteristics- how much can they concentrate by 1 week, 2, and adult

Answer 22

Cant concentrate urine, so they pee it out
1st week- 70%
2nd- 84%
Adult- 99.5%

Question 23

Adult vs neonate urine na levels

Answer 23

5-10
20-25

Question 24

Lowest hgb hct

Answer 24

35%, 11

Question 25

blood volume in pre term and term baby

Answer 25

Pre term- 100 ml/kg
Term- 90 ml/kg

Question 26

stages of heat loss

Answer 26

1- transfer from body core to skin surface (internal gradient)
2- dissipation from surface to environment (external gradient)

Question 27

Thermal regulation- 3 things that babys use

Answer 27

Non shivering thermogenesis major
Voluntary muscle activity
Involuntary muscle activity

Question 28

What is non shivering thermogensis, when does it start, where located

Answer 28

neonates warming mechanism
metabolism of brown fat- 5% of tbw
Develops by week 30
Located in the mediastinum, scapula, adrenals, axilla

Question 29

What is non shivering thermogenesis mediated from

Answer 29

sympathetic nervous system

Question 30

Cold stress consequences

Answer 30

Increased o2 consumption- hypoxia, acidosis
Increased glucose utilization- lactic acid, hypoglycemia
Decrease surfactant- collapse of alveoli, reopening of fetal shunts

Question 31

Prevent conduction heat loss

Answer 31

warm blankets, bair hugger

Question 31

Prevent convection heat loss

Answer 31

High room temp

Question 32

Prevent radiation HL

Answer 32

French fry lights

Question 33

Prevent evaporation HL

Answer 33

Cover exposed body cavities, heat, and inspired gases

Question 34

How does the ductus arteriosis close, what three things is it sensitive to

Answer 34

Aorta turns into high pressure, and pulmonary artery turns low (both are switched)
high pao2
high Bradykinin
Low Prostaglandin E2

Question 35

SPO2 of umbilical artery and vein

Answer 35

Artery 58%
Vein 80%