Fluid Across Pulmonary Capillaries & Destruction of Alveoli

Question 1

What is PO2 at sea level?

Answer 1

160 mmHg

Question 2

What is PO2 at 18 000 feet?

Answer 2

80 mmHg

Question 3

How is pulmonary circulation re: pressure and resistance?

Answer 3

Low pressure

Low resistance

Question 4

What is mean Pulmonary artery pressure? PAP

Answer 4

15 mmHg

Question 5

What is mean Capillary pressure?

Answer 5

8-12 mmHg

Question 6

What is the right ventricular out put at rest? at max?

Answer 6

5-20L/min same as left ventricle

Question 7

Does pulmonary artery pressure rise with exercise? Why?

Answer 7

Nope. Due to dilation/recruitment of pulmonary vessels

Question 8

When you lie down, blood drains from your legs to this reservoir?

Answer 8

Pulmonary Circulation

Question 9

What does pulmonary systolic BP do on inspiration?

Answer 9

decreases

Question 10

What happens to pulmonary CO and venous return on inspiration?

Answer 10

both decrease

Question 11

How do you get increased leakage of fluid across pulmonary capillaries?

Answer 11

increased pulmonary artery pressure

Question 12

What are crepitations?

Answer 12

crackles

Question 13

Why do the lungs ‘crackle’?

Answer 13

air bubbles travelling through fluid in alveoli

Question 14

What are Kerley B lines?

Answer 14

dilated lymphatics in lung on CXR cause they are trying to drain at an increased rate

Question 15

pH = 7.26
PaO2 = 45mmHg
PaCo2 = 28mmHg
Na+ = 138mmol/l
K+ = 5mmol/l
Cl-=100mmol/l
HCO3-=15 mmol/l

Answer 15

Metabolic acidosis

Question 16

How do you get fluid out of capillaries in pulmonary oedema?

Answer 16

increased pulmonary capillary hydrostatic pressure

Question 17

3 factors that determine fluid movement across pulmonary capillaries:

Answer 17

hydrostatic pressure in and out cap
oncotic pressure in and out
permeability of capillary

Question 18

What is Pc and Pi

Oc and Oi

Answer 18

Pc: hydrostatic pressure outside capillary
Pi: hydrostatic pressure inside capillary
Oc: Oncotic Pressure outside capillary
Oi: Oncotic Pressure inside capillary

Question 19

What is the usual Pc/Pi?

Answer 19

Pc>Pi

Question 20

What is the usual Oc/Oi?

Answer 20

Oc>Oi

Question 21

When a patient all of a sudden gets anxious what does that mean?

Answer 21

Be worried, shit is about to get real.

Question 22

What is type 1 respiratory failure?

Answer 22

hypoxia without hypercapnia, and indeed the PaCO2 may be normal or low due to V/Q mismatch

Question 23

What does ARDS cause in terms of lungs?

Answer 23

stiff lungs, increase elastic work

Small and stiff lungs

Question 24

What is the normal lymphatic flow in lungs?

Answer 24

20ml/hour

Question 25

4 mechanical changes in pulmonary oedema

Answer 25

decrease lung compliance
decrease lung volume
increase airway resistance
increase work of breathing

Question 26

What happens to gas exchange in pulmonary oedema?

Answer 26

hypoxaemia due to shunting

Question 27

What is a key fature on CXR for non-cardiogenic pulmonary edema?

Answer 27

normal heart size

Question 28

Arterial blood gases in pulmonary oedema?

Answer 28

low PaO2
low PaCO2
increased pH
type 1 resp failure

Question 29

Arterial blood gases in severe pulmonary oedema?

Answer 29

low PaO2
High PaCO2
low pH
Type 2 respiratory failure

Question 30

Changes in pulmonary circulation during pulmonary oedema?

Answer 30

increase pulmonary vascular resistance

Question 31

T/F Alveolar epithelium likes water, ions etc.?

Answer 31

False, it actively pumps water from alveoli into interstitial spaces

Question 32

Does interstitial oedema cause functional effects?

Answer 32

Not really, it’s alveolar oedema that will mess up your day

Question 33

2 common causes of pulmonary oedema?

Answer 33

increased capillary hydrostatic pressure (L ventricular dysfunction, mitral stenosis, fluid overload, pulmonary veno-occlusive disease)
increased capillary permeability (toxins, spesis, trauma)

Question 34

2 less common causes/exacerbations of pulmonary oedema?

Answer 34

decreased colloid osmotic pressure

decreased lymphatic drainage