Lung Flashcards
Breath out alveoli
Decrease radius of alveoli may collapse
Collapsing p=2xST/r
Type 1 pneumocytes
Thin
Line the alveoli
Facilitate gas exchange
Type 2
Secrete surfactant
-protect against collapse
Where is surfactant made
Lamellar bodies
What does surfactant do
Decrease surface tension
- prevents alveolar collapse
- decrease recoil
- increase compliance
Composition surfactant
Many lecitihins
DPPC
When get surfactant
20, mature at 35
Alveolar macrophages
Eat and release cytokines and alveolar proteases
In pulmonary hemorrhage see hemosiderin laden macrophages
Pulmonary hemorrhage
Hemosiderin laden macrophages
FEV1
Forced exploratory volume in 1 sec
FVC
Forced vital capacity
Volume of air that can be forcefully blown out after full inspiration
Normal FEV1/FVC
4/5 about 80%
Can blow out 4 l in 1 s and 5 in total
Obstructive
Emphysema and asthma
Total airvolumes larger, more air any any time
Air trapping-cant get rid of air,
FEV1 and FVC decrease
FVC more
Less than 80%
Restrictive lung disease
Volume abnormal but lung volume decrease
Can’t fill lung very well, obese sarcoidosis
Can’t get s much air into lungFEV1/FVC over 80%
FEV1/fvc decrease but proportionally
Absolute value of FEV1 and fvc
Both decrease but ration close to normal
Hemoglobin
4 polypeptide 2a 2b
2 forms hemoglobin
Oxygenated and deoxygenated
Deoxygenation shift
Right shift
23bpg
Stabilize hemoglobin in low oxygen state
Fetal hemoglobin
2 gamma
Higher affinity for oxygen
Does not bind well to 2,3 BPH
Myoglobin
Single poly peptide
1 heme
High affinity for oxygen
Only in muscle
High blood levels of myoglobin
Muscle injury
Alveolar gas equation
A-alveolar
A-gas in artery
PAo2=PIo2-PaCo2/R
PIo2-breathing in
R=.8
A:a gradient
Alveolar oxygen/-arterial
Normally 10-15
Up-cant get from alveoli into blood
-shunting, VQ mismatch fibrosis
