Erythropoietin: Regulator of Erythropoiesis · mixture of gases is equal to the sum of the partial...
Transcript of Erythropoietin: Regulator of Erythropoiesis · mixture of gases is equal to the sum of the partial...
![Page 1: Erythropoietin: Regulator of Erythropoiesis · mixture of gases is equal to the sum of the partial pressure of all gases ... (at Sea Level) Atmospheric Air* Alveolar Air Expired Air](https://reader033.fdocuments.in/reader033/viewer/2022052800/5f0f3e647e708231d443327d/html5/thumbnails/1.jpg)
1
![Page 2: Erythropoietin: Regulator of Erythropoiesis · mixture of gases is equal to the sum of the partial pressure of all gases ... (at Sea Level) Atmospheric Air* Alveolar Air Expired Air](https://reader033.fdocuments.in/reader033/viewer/2022052800/5f0f3e647e708231d443327d/html5/thumbnails/2.jpg)
Competency
2
No. PY6.2 (Respiratory Physiology)
CompetencyDescribe the V/P ratio & diffusion capacity of lungs.
D/L/Core K/KH/Y
AM Written/Viva voce
Integration No
Imp. Concept Clinical significance of V/P
Phy. TriviaCO is diffusion-limited & N2O is perfusionlimited
![Page 3: Erythropoietin: Regulator of Erythropoiesis · mixture of gases is equal to the sum of the partial pressure of all gases ... (at Sea Level) Atmospheric Air* Alveolar Air Expired Air](https://reader033.fdocuments.in/reader033/viewer/2022052800/5f0f3e647e708231d443327d/html5/thumbnails/3.jpg)
3
![Page 4: Erythropoietin: Regulator of Erythropoiesis · mixture of gases is equal to the sum of the partial pressure of all gases ... (at Sea Level) Atmospheric Air* Alveolar Air Expired Air](https://reader033.fdocuments.in/reader033/viewer/2022052800/5f0f3e647e708231d443327d/html5/thumbnails/4.jpg)
4
![Page 5: Erythropoietin: Regulator of Erythropoiesis · mixture of gases is equal to the sum of the partial pressure of all gases ... (at Sea Level) Atmospheric Air* Alveolar Air Expired Air](https://reader033.fdocuments.in/reader033/viewer/2022052800/5f0f3e647e708231d443327d/html5/thumbnails/5.jpg)
OUTLINE
• Physics law
• Respiratory membrane
• Diffusion capacity of lung
5
![Page 6: Erythropoietin: Regulator of Erythropoiesis · mixture of gases is equal to the sum of the partial pressure of all gases ... (at Sea Level) Atmospheric Air* Alveolar Air Expired Air](https://reader033.fdocuments.in/reader033/viewer/2022052800/5f0f3e647e708231d443327d/html5/thumbnails/6.jpg)
Physics law
• Gas pressure:
P=nRT/V
• Dalton law:
Partial pressure
• Henry’s law:
n=pc
6
According to the Henry’s law, whentemperature is kept constant, the contentof gas (n) dissolved in any solution isdirectly proportional to the partialpressure of a gas,
The total pressure exerted by amixture of gases is equal to the sumof the partial pressure of all gasespresent in the mixture
![Page 7: Erythropoietin: Regulator of Erythropoiesis · mixture of gases is equal to the sum of the partial pressure of all gases ... (at Sea Level) Atmospheric Air* Alveolar Air Expired Air](https://reader033.fdocuments.in/reader033/viewer/2022052800/5f0f3e647e708231d443327d/html5/thumbnails/7.jpg)
Partial Pressures of Respiratory Gases as They Enter and Leave the Lungs (at Sea Level)
Atmospheric Air* Alveolar Air Expired Air(mm Hg) (mm Hg) (mm Hg)
N2 596
O2 158
CO2 0.3
H2O 5.7
TOTAL 760
On an average cool, clear day.
![Page 8: Erythropoietin: Regulator of Erythropoiesis · mixture of gases is equal to the sum of the partial pressure of all gases ... (at Sea Level) Atmospheric Air* Alveolar Air Expired Air](https://reader033.fdocuments.in/reader033/viewer/2022052800/5f0f3e647e708231d443327d/html5/thumbnails/8.jpg)
Partial Pressures of Respiratory Gases as They Enter and Leave the Lungs (at Sea Level)
Atmospheric Air* Alveolar Air (mm Hg) (mm Hg)
N2 596 573
O2 158 100
CO2 0.3 40
H2O 5.7 47
TOTAL 760 760
On an average cool, clear day.
![Page 9: Erythropoietin: Regulator of Erythropoiesis · mixture of gases is equal to the sum of the partial pressure of all gases ... (at Sea Level) Atmospheric Air* Alveolar Air Expired Air](https://reader033.fdocuments.in/reader033/viewer/2022052800/5f0f3e647e708231d443327d/html5/thumbnails/9.jpg)
Partial Pressures of Respiratory Gases as They Enter and Leave the Lungs (at Sea Level)
Atmospheric Air* Alveolar Air Expired Air(mm Hg) (mm Hg) (mm Hg)
N2 596 573 565
O2 158 100 116
CO2 0.3 40 32
H2O 5.7 47 47
TOTAL 760 760 760
On an average cool, clear day.
![Page 10: Erythropoietin: Regulator of Erythropoiesis · mixture of gases is equal to the sum of the partial pressure of all gases ... (at Sea Level) Atmospheric Air* Alveolar Air Expired Air](https://reader033.fdocuments.in/reader033/viewer/2022052800/5f0f3e647e708231d443327d/html5/thumbnails/10.jpg)
Alveolar air
i) Composition-
ii) Characteristics-
iii) Collection-
Haldane-
Priestly tube
100
![Page 11: Erythropoietin: Regulator of Erythropoiesis · mixture of gases is equal to the sum of the partial pressure of all gases ... (at Sea Level) Atmospheric Air* Alveolar Air Expired Air](https://reader033.fdocuments.in/reader033/viewer/2022052800/5f0f3e647e708231d443327d/html5/thumbnails/11.jpg)
11
![Page 12: Erythropoietin: Regulator of Erythropoiesis · mixture of gases is equal to the sum of the partial pressure of all gases ... (at Sea Level) Atmospheric Air* Alveolar Air Expired Air](https://reader033.fdocuments.in/reader033/viewer/2022052800/5f0f3e647e708231d443327d/html5/thumbnails/12.jpg)
12
![Page 13: Erythropoietin: Regulator of Erythropoiesis · mixture of gases is equal to the sum of the partial pressure of all gases ... (at Sea Level) Atmospheric Air* Alveolar Air Expired Air](https://reader033.fdocuments.in/reader033/viewer/2022052800/5f0f3e647e708231d443327d/html5/thumbnails/13.jpg)
Diffusion across the R membrane…..
Site
Respiratory zone/unit;
• Respiratory bronchioles,
• Alveolar ducts
• Alveoli
13
![Page 14: Erythropoietin: Regulator of Erythropoiesis · mixture of gases is equal to the sum of the partial pressure of all gases ... (at Sea Level) Atmospheric Air* Alveolar Air Expired Air](https://reader033.fdocuments.in/reader033/viewer/2022052800/5f0f3e647e708231d443327d/html5/thumbnails/14.jpg)
Diffusion across the R membrane…..
Respiratory membrane
(alveolar-capillary Membrane)
1. Structure-
2. Surface area-
3. Thickness-
14
![Page 15: Erythropoietin: Regulator of Erythropoiesis · mixture of gases is equal to the sum of the partial pressure of all gases ... (at Sea Level) Atmospheric Air* Alveolar Air Expired Air](https://reader033.fdocuments.in/reader033/viewer/2022052800/5f0f3e647e708231d443327d/html5/thumbnails/15.jpg)
15
![Page 16: Erythropoietin: Regulator of Erythropoiesis · mixture of gases is equal to the sum of the partial pressure of all gases ... (at Sea Level) Atmospheric Air* Alveolar Air Expired Air](https://reader033.fdocuments.in/reader033/viewer/2022052800/5f0f3e647e708231d443327d/html5/thumbnails/16.jpg)
Structure of respiratory mem.
→ Fluid with surfactant
→ Alveolar squamous epithelium
→ Basement membrane
→ Interstitial fluid
→ Capillary basement membrane
→ Capillary endothelium.
Thickness only .5 micron
Surface area 70 m2
![Page 17: Erythropoietin: Regulator of Erythropoiesis · mixture of gases is equal to the sum of the partial pressure of all gases ... (at Sea Level) Atmospheric Air* Alveolar Air Expired Air](https://reader033.fdocuments.in/reader033/viewer/2022052800/5f0f3e647e708231d443327d/html5/thumbnails/17.jpg)
17
![Page 18: Erythropoietin: Regulator of Erythropoiesis · mixture of gases is equal to the sum of the partial pressure of all gases ... (at Sea Level) Atmospheric Air* Alveolar Air Expired Air](https://reader033.fdocuments.in/reader033/viewer/2022052800/5f0f3e647e708231d443327d/html5/thumbnails/18.jpg)
Process-
O2 & CO2 being lipid soluble diffuses across respiratory
membrane according to fick’s law
Factors affecting the diffusion-
1) Inversely proportional to thickness (d) of R. membrane.
2) Directly ∝ to surface area (A) of R. mem.
3) Directly ∝ to partial pressure gradient of gasses
4) Directly ∝ to diffusion coefficient of gasses, which in
turn Is directly ∝ to gas solubility (S) & inversely ∝ to
square root of molecular weight (MW)
![Page 19: Erythropoietin: Regulator of Erythropoiesis · mixture of gases is equal to the sum of the partial pressure of all gases ... (at Sea Level) Atmospheric Air* Alveolar Air Expired Air](https://reader033.fdocuments.in/reader033/viewer/2022052800/5f0f3e647e708231d443327d/html5/thumbnails/19.jpg)
Diffusion capacity (DL) of lungs
1) Definition-,
2) Normal Value-
3) Measurement-
Factors affecting (3 Ps)
5) Physical (determinants)-
6) Physiological- (exercise)
7) Pathological (Clinical)-
![Page 20: Erythropoietin: Regulator of Erythropoiesis · mixture of gases is equal to the sum of the partial pressure of all gases ... (at Sea Level) Atmospheric Air* Alveolar Air Expired Air](https://reader033.fdocuments.in/reader033/viewer/2022052800/5f0f3e647e708231d443327d/html5/thumbnails/20.jpg)
20
![Page 21: Erythropoietin: Regulator of Erythropoiesis · mixture of gases is equal to the sum of the partial pressure of all gases ... (at Sea Level) Atmospheric Air* Alveolar Air Expired Air](https://reader033.fdocuments.in/reader033/viewer/2022052800/5f0f3e647e708231d443327d/html5/thumbnails/21.jpg)
21
N2O is flow-limited
CO is diffusion-limited
https://youtu.be/h-IfQBVcnqM
![Page 22: Erythropoietin: Regulator of Erythropoiesis · mixture of gases is equal to the sum of the partial pressure of all gases ... (at Sea Level) Atmospheric Air* Alveolar Air Expired Air](https://reader033.fdocuments.in/reader033/viewer/2022052800/5f0f3e647e708231d443327d/html5/thumbnails/22.jpg)
22
![Page 23: Erythropoietin: Regulator of Erythropoiesis · mixture of gases is equal to the sum of the partial pressure of all gases ... (at Sea Level) Atmospheric Air* Alveolar Air Expired Air](https://reader033.fdocuments.in/reader033/viewer/2022052800/5f0f3e647e708231d443327d/html5/thumbnails/23.jpg)
Diffusion capacity (DL) of lungs
i) Definition
is the amount of the gas that diffuses thro.
respiratory membrane / minute /unit or mm Hg difference in
partial pressure of the gas on the two sides of the
membrane.
ii) Value
DL of O2 is 20-25 ml/min/mmHg at rest while of CO2 is 400
ml/min/mmHg, (20 times more than O2)
iii) Measurement
indirectly by measuring DL of CO
![Page 24: Erythropoietin: Regulator of Erythropoiesis · mixture of gases is equal to the sum of the partial pressure of all gases ... (at Sea Level) Atmospheric Air* Alveolar Air Expired Air](https://reader033.fdocuments.in/reader033/viewer/2022052800/5f0f3e647e708231d443327d/html5/thumbnails/24.jpg)
iv) Physical factors (determinants) affecting DL-
∝ to surface area (A ) of R membrane
Inversely ∝ thickness (d) of R membrane
∝ to gas solubility (S) of the gas
Inversely ∝ to square root molecular weight (MW) of gas
v) Physiological factors affecting DL-
exercise (as new capillaries open & SA can ↑ up to 3 times)
vi) Pathological (clinical) factors ↓ing DL-
in lobectomy & emphysema due to ↓ SA while in
pulmonary edema, pulmonary fibrosis due to ↑ thickness
![Page 25: Erythropoietin: Regulator of Erythropoiesis · mixture of gases is equal to the sum of the partial pressure of all gases ... (at Sea Level) Atmospheric Air* Alveolar Air Expired Air](https://reader033.fdocuments.in/reader033/viewer/2022052800/5f0f3e647e708231d443327d/html5/thumbnails/25.jpg)
25
![Page 26: Erythropoietin: Regulator of Erythropoiesis · mixture of gases is equal to the sum of the partial pressure of all gases ... (at Sea Level) Atmospheric Air* Alveolar Air Expired Air](https://reader033.fdocuments.in/reader033/viewer/2022052800/5f0f3e647e708231d443327d/html5/thumbnails/26.jpg)
Ventilation perfusion ratio- VA/Q ratio
1) Definition-,
2) Normal Value-
Factors affecting
5) Physical (relation with PO2 & PCO2
6) Physiological- (gravity)
7) Pathological (Clinical)-
![Page 27: Erythropoietin: Regulator of Erythropoiesis · mixture of gases is equal to the sum of the partial pressure of all gases ... (at Sea Level) Atmospheric Air* Alveolar Air Expired Air](https://reader033.fdocuments.in/reader033/viewer/2022052800/5f0f3e647e708231d443327d/html5/thumbnails/27.jpg)
Ventilation perfusion ratio- VA/Q ratio
i) Definition (VA/Q ratio)-
is the ratio of alveolar ventilation and pulmonary blood
flow
ii) Value-
VA/Q ratio = alveolar ventilation 4200 ml/ pulmonary blood
flow 5000 ml = 0.8 (normal gas exchange)
iii) Physical factors affecting VA/Q ratio-
Relation with PAO2 / PACO2-
↑ value of VA/Q ratio ↑es PAO2 & ↓es PACO2
while ↓ value of VA/Q ratio ↓es PAO2 & ↑es PACO2
![Page 28: Erythropoietin: Regulator of Erythropoiesis · mixture of gases is equal to the sum of the partial pressure of all gases ... (at Sea Level) Atmospheric Air* Alveolar Air Expired Air](https://reader033.fdocuments.in/reader033/viewer/2022052800/5f0f3e647e708231d443327d/html5/thumbnails/28.jpg)
28
![Page 29: Erythropoietin: Regulator of Erythropoiesis · mixture of gases is equal to the sum of the partial pressure of all gases ... (at Sea Level) Atmospheric Air* Alveolar Air Expired Air](https://reader033.fdocuments.in/reader033/viewer/2022052800/5f0f3e647e708231d443327d/html5/thumbnails/29.jpg)
29
![Page 30: Erythropoietin: Regulator of Erythropoiesis · mixture of gases is equal to the sum of the partial pressure of all gases ... (at Sea Level) Atmospheric Air* Alveolar Air Expired Air](https://reader033.fdocuments.in/reader033/viewer/2022052800/5f0f3e647e708231d443327d/html5/thumbnails/30.jpg)
Ventilation perfusion ratio-VA/Q ratio
![Page 31: Erythropoietin: Regulator of Erythropoiesis · mixture of gases is equal to the sum of the partial pressure of all gases ... (at Sea Level) Atmospheric Air* Alveolar Air Expired Air](https://reader033.fdocuments.in/reader033/viewer/2022052800/5f0f3e647e708231d443327d/html5/thumbnails/31.jpg)
Ventilation perfusion ratio-VA/Q ratio
At apex-Physiological Dead space, T.B.
At base-Physiological shunt (shunted
blood)
![Page 32: Erythropoietin: Regulator of Erythropoiesis · mixture of gases is equal to the sum of the partial pressure of all gases ... (at Sea Level) Atmospheric Air* Alveolar Air Expired Air](https://reader033.fdocuments.in/reader033/viewer/2022052800/5f0f3e647e708231d443327d/html5/thumbnails/32.jpg)
(iv) Physiological factors affecting VA/Q ratio-
Effect of gravity-
at the apex of lungs (wasted ventilation)
- VA/Q ratio ↑es & is 3 x normal (as Q ↓es due to gravity)
- So ↑ PAO2 & ↓ PACO2
- This create physiological dead space at apex and
- make apex vulnerable to T.B. (tuberculosis) due to ↑ PAO2
while at the base of lungs (wasted perfusion)
- VA/Q ratio ↓es & is .6 x normal (as Q ↑ es due to gravity)
- so ↓ PAO2 & ↑ PACO2
- & this create physiological shunt (shunted blood) at base.
![Page 33: Erythropoietin: Regulator of Erythropoiesis · mixture of gases is equal to the sum of the partial pressure of all gases ... (at Sea Level) Atmospheric Air* Alveolar Air Expired Air](https://reader033.fdocuments.in/reader033/viewer/2022052800/5f0f3e647e708231d443327d/html5/thumbnails/33.jpg)
in extreme case (no gas exchange)
complete obstruction of
pulmonary artery
complete bronchial obstruction
![Page 34: Erythropoietin: Regulator of Erythropoiesis · mixture of gases is equal to the sum of the partial pressure of all gases ... (at Sea Level) Atmospheric Air* Alveolar Air Expired Air](https://reader033.fdocuments.in/reader033/viewer/2022052800/5f0f3e647e708231d443327d/html5/thumbnails/34.jpg)
complete obstruction of
pulmonary artery
i) PO2/PCO2 equals
humidified inspired air
ii) No gaseous exchange
complete bronchial obstruction
i) PO2/PCO2 equals
Venous blood
ii) No gaseous exchange
![Page 35: Erythropoietin: Regulator of Erythropoiesis · mixture of gases is equal to the sum of the partial pressure of all gases ... (at Sea Level) Atmospheric Air* Alveolar Air Expired Air](https://reader033.fdocuments.in/reader033/viewer/2022052800/5f0f3e647e708231d443327d/html5/thumbnails/35.jpg)
vi) Pathological (clinical) factors VA/Q ratio-
in bronchial obstruction VA/Q ratio ↓es while
obstruction of pulmonary artery ↑es VA/Q ratio.
in extreme case (no gas exchange)
- ratio is infinite if there is complete obstruction of
pulmonary artery then PAO2 will be 149 & PACO2 will be
0.3 mmHg equal to humidified inspired air.
- ratio is zero if there is complete bronchial obstruction
then PAo2 will be 40 & PAco2 45 mmHg that is equal to
mixed venous blood.
![Page 36: Erythropoietin: Regulator of Erythropoiesis · mixture of gases is equal to the sum of the partial pressure of all gases ... (at Sea Level) Atmospheric Air* Alveolar Air Expired Air](https://reader033.fdocuments.in/reader033/viewer/2022052800/5f0f3e647e708231d443327d/html5/thumbnails/36.jpg)
36
![Page 37: Erythropoietin: Regulator of Erythropoiesis · mixture of gases is equal to the sum of the partial pressure of all gases ... (at Sea Level) Atmospheric Air* Alveolar Air Expired Air](https://reader033.fdocuments.in/reader033/viewer/2022052800/5f0f3e647e708231d443327d/html5/thumbnails/37.jpg)
37
![Page 38: Erythropoietin: Regulator of Erythropoiesis · mixture of gases is equal to the sum of the partial pressure of all gases ... (at Sea Level) Atmospheric Air* Alveolar Air Expired Air](https://reader033.fdocuments.in/reader033/viewer/2022052800/5f0f3e647e708231d443327d/html5/thumbnails/38.jpg)
38