Respiratory Distress Syndrome Flashcards Preview

ICM -- Pulmonology > Respiratory Distress Syndrome > Flashcards

Flashcards in Respiratory Distress Syndrome Deck (37):
1

Common causes of respiratory distress in newborns

RDS
Airleak (pneumothorax)
Meconium Aspiration Syndrome
Neonatal Pneumonia
Pulmonary Hemorrhage

2

Acrocyanosis

Cyanosis of the periphery (blue nails)

3

Cause of RDs

Deficiency of surfactant in premature babies.
Leads to poorly compliant lungs, atelectasis, increased work to breathe, and hypoxia

4

Likelihood of RDS at 29 week gestation? Full Term?

60%
near 0%

5

Risk factors for RDS?

Fetal hyperinsulinism
Fetal asphyxia
Multiple gestations
Male>Female
Caucasian>Black

6

Five stages of lung development

Embryonic
Pseudoglandular
Canacular
___- (who fucking knows)
Alveolar

7

Embryonic period lasts from
What forms

0-6 weeks, bronchi develop

8

Pseudoglandular period happens from
What forms

7-16 weeks
COnducting airways, Branching pattern

9

Canalicular period happens from...
what forms?

17-25 weeks
Acini
Resp bronchiole, alveolar duct+Sac
Type II alveolar cells (20 weeks)

10

Subsaccular period happens from...
what forms?

25-35 weeks
Primitive alveoli
Decrese inerstitial thickness, eparate terminal air units
Type I and II differentiate
Lamellar bodies develop

11

Alveolar period happens from...
what forms?

36 w-3yo
- Invagination of terminal saccules and formation of secondary perfusion
- Collagen synthesis
- Further interstitial thinning
- Appearance of a single capillary network.

12

Anything born before _____ is a non-viable birth

20 weeks
You've got no lung to work with

13

What is surfactant

A lipoprotein -- Saturated phosphatidylcholine

14

Surfactant is made where?

Smooth ER of Type II Alveolar Cells

15

Surfactant in stored intracellularly where?

Lamellar Bodies

16

Surfactant is converted to...

Tubular myelin

17

Who has a regulatory role in surfactant production?

Steroids and thyroid hormones

18

_____ stimulate the Surfactant secretion at birth

Catecholamine surge and Lung distention

19

What does SP-A do?

Forms an integral part of tubular myein
Inhibits secretion, but stimulates reutilization
Role in determinine surfactant pool size

20

What does SP-D do?

Innate host defense from viral infections
Surfactant lipid homeostasis
Protect from oxidant damage

21

What does SP-B do?

Surface tension reduction
Formation of Lamellar bodies + Tubular myelin

22

What does SP-C do?

Surface absorption of phospholipids

23

Agents that inhibit surfactant fxn

AMNIOTIC FLUID + MECONIUM
Albumin, Bilirubin, Cholesterol, Elastin, Blood products

24

Law of Laplace =

Pressure to keep it open = 2Tension / radius

25

Pressure required to keep an alveoli open is ____ to surface tension and _____ to alveolar radius

directly proportional
inversely proportional

26

Relationship between Surfactant and law of laplace

Surhactant lowers surface tension by displacing water molecules, helps alveoli not close on expiration

27

RDS pathogenesis

Deficient surfactant at air-fluid interfact caused by secretion problem. Causes atelectasis. Other alveoli distend and epithelial damage occurs.

28

Effects of no surfactant on alveoli fxn

Poor stability
R to L shunting of blood
Reduced effective pulmonary BF
Edema
Decreased Compliance

29

How to diagnose RDS Clinically?

Premature infants
Tachypnea, Central Cyanosis, Labored breathing
Retractions, Flaring, Grunting
Auscultation may reveal fine rales

30

Why do adults inspire by chest out while RDS babies go in

In adults, compliance + negative pressure will do it
Babies are less compliant lungs and ribs are still too soft.
Negative pressure causes the rib cage to collapse instead of making the lungs expand

31

How to diagnose RDS in Lab studies?

Hypoxia, Hypercarbia, Acidosis

32

How to diagnose RDS -- Radiographic?

Granular densities within hours
Ground Glass appearance

33

How to prevent RDS?

Reduce preterm births
Predict at risk pregnancies, treat with antenatal glucocorticoid hormones
Prophylactic/Early treatment of high risk infants with exogenous surfactant in delivery room

34

RDS Treatment

Resuscitation by skilled team
Intratracheal administration of exogenous surfactant
Neonatal care (temp, infection control, nutrition, fluids)
Assisted ventilation

35

What does grunting do for baby?

Adds resistance via closed glottis
More pressure
Keeps lung/alveoli open

36

Potential outcomes of RDS

Recovery
Barotrauma/Volutrauma
Chronic lung disease
Intraventricular Hemorrhage, Retinopathy of Prematurity
Death

37

PDA closed with...

Endomethacin