iphy 3430 2-15-11. review: during inhalation/exhalation at rest: pressure differential of about 1 mm...

21
IPHY 3430 2-15-11

Upload: andrea-ray

Post on 14-Jan-2016

216 views

Category:

Documents


0 download

TRANSCRIPT

Page 1: IPHY 3430 2-15-11. Review: During inhalation/exhalation at rest: pressure differential of about 1 mm 759 mmHg 760 Inhalation at rest 761 760 Exhalation

IPHY 3430 2-15-11

Page 2: IPHY 3430 2-15-11. Review: During inhalation/exhalation at rest: pressure differential of about 1 mm 759 mmHg 760 Inhalation at rest 761 760 Exhalation

Review:During inhalation/exhalation at rest:pressure differential of about 1 mm

759mmHg

760

Inhalation at rest

761

760

Exhalation at rest

Page 3: IPHY 3430 2-15-11. Review: During inhalation/exhalation at rest: pressure differential of about 1 mm 759 mmHg 760 Inhalation at rest 761 760 Exhalation

Review:

During exercise, pressure differentials greater than 1 mm generated due to greater numbers of muscles contracting with greater force, resulting in larger expansion of thoracic cavity and lungs.

750

760mmHg 770

760ExhalationInhalation

Page 4: IPHY 3430 2-15-11. Review: During inhalation/exhalation at rest: pressure differential of about 1 mm 759 mmHg 760 Inhalation at rest 761 760 Exhalation

So,…..

Quiet breathing: 500 ml x 12 b/m = 6 L/min

Exercise: 2300 ml x 40-50 b/m = 100-120 L/ min

Page 5: IPHY 3430 2-15-11. Review: During inhalation/exhalation at rest: pressure differential of about 1 mm 759 mmHg 760 Inhalation at rest 761 760 Exhalation
Page 6: IPHY 3430 2-15-11. Review: During inhalation/exhalation at rest: pressure differential of about 1 mm 759 mmHg 760 Inhalation at rest 761 760 Exhalation

Factors that can affect gas exchange by influencing flow and lung volumeAir Flow = P/ resistance

SNS --bronchodilationPNS--bronchoconstriction

Chronic obstructive pulmonary disease (COPD)Asthma,emphysema, chronic bronchitis

Factors that reduce lung volume: pneumonia, cancer, tuberculosis

Page 7: IPHY 3430 2-15-11. Review: During inhalation/exhalation at rest: pressure differential of about 1 mm 759 mmHg 760 Inhalation at rest 761 760 Exhalation

Gas exchange

Between outside air and lungs= convection

Between alveolar air and blood = diffusion

Diffusion rate = P x surface area x solubility coefficient distance x M.W.1/2

Page 8: IPHY 3430 2-15-11. Review: During inhalation/exhalation at rest: pressure differential of about 1 mm 759 mmHg 760 Inhalation at rest 761 760 Exhalation

Physical principles governing diffusion1. Gases diffuse down partial pressure gradient (PO2, PCO2, PN2, etc)2. Diffusion of one gas unaffected by diffusion of another3. In lungs, all gases diffuse through water 4. The bigger the partial pressure gradient, the faster the rate of diffusion.

Page 9: IPHY 3430 2-15-11. Review: During inhalation/exhalation at rest: pressure differential of about 1 mm 759 mmHg 760 Inhalation at rest 761 760 Exhalation
Page 10: IPHY 3430 2-15-11. Review: During inhalation/exhalation at rest: pressure differential of about 1 mm 759 mmHg 760 Inhalation at rest 761 760 Exhalation

Partial pressures of gases (mm Hg)

Gas Air AlveolarN2 597 (78.6%) 569 (74.9%)O2 159 (20.8%) 104 (13.6%)CO2 0.3 ( 0.04%) 40 (5.3%)H20 3.7 (0.5%) 47 (6.2%)

760 760

Page 11: IPHY 3430 2-15-11. Review: During inhalation/exhalation at rest: pressure differential of about 1 mm 759 mmHg 760 Inhalation at rest 761 760 Exhalation
Page 12: IPHY 3430 2-15-11. Review: During inhalation/exhalation at rest: pressure differential of about 1 mm 759 mmHg 760 Inhalation at rest 761 760 Exhalation

Oxygen Diffusion at rest

Air--> alveoli-->arteriolar blood--> cells(159) (100) (100) (40)

lungs

venous

arteriolar

cells100

100

40 40 PO2 = 60

PO2 = 60

Page 13: IPHY 3430 2-15-11. Review: During inhalation/exhalation at rest: pressure differential of about 1 mm 759 mmHg 760 Inhalation at rest 761 760 Exhalation

Oxygen Diffusion during exercise

Air--> alveoli-->arteriolar blood--> cells(159) (100) (100) (20)

lungs

venous

arteriolar

cells100

100

20 20 PO2 = 80

PO2 = 80

Page 14: IPHY 3430 2-15-11. Review: During inhalation/exhalation at rest: pressure differential of about 1 mm 759 mmHg 760 Inhalation at rest 761 760 Exhalation

CO2 Diffusion during rest

Air<-- alveoli <--venous blood <-- cells (.3) (40) (46) (46)

lungs

venous

arteriolar

cells40

40

46 46 PCO2 = 6

PCO2 = 6

Page 15: IPHY 3430 2-15-11. Review: During inhalation/exhalation at rest: pressure differential of about 1 mm 759 mmHg 760 Inhalation at rest 761 760 Exhalation

CO2 Diffusion during exercise

Air<-- alveoli <--venous blood <-- cells (.3) (40) (55) (55)

lungs

venous

arteriolar

cells40

40

55 55 PCO2 = 15

PCO2 = 15

Page 16: IPHY 3430 2-15-11. Review: During inhalation/exhalation at rest: pressure differential of about 1 mm 759 mmHg 760 Inhalation at rest 761 760 Exhalation

During exercise: Alveolar PO2 (104) and PCO2 (40) MUSTbe maintained at those levels by increased rate and depth of ventilation in order to ensure that partial pressure gradients are as large as possible.Air<-- alveoli <--venous blood <-- cells (.3) (40) (55) (55)

lungs

venous

arteriolar

cells40

40

55 55 PCO2 = 15

PCO2 = 15

CO2 mustrise

Page 17: IPHY 3430 2-15-11. Review: During inhalation/exhalation at rest: pressure differential of about 1 mm 759 mmHg 760 Inhalation at rest 761 760 Exhalation
Page 18: IPHY 3430 2-15-11. Review: During inhalation/exhalation at rest: pressure differential of about 1 mm 759 mmHg 760 Inhalation at rest 761 760 Exhalation

High AltitudeAltitude Pb PO2 Alveolar PO2sea level 760 159 104 10,000 523 110 67 20,000 349 73 40

Page 19: IPHY 3430 2-15-11. Review: During inhalation/exhalation at rest: pressure differential of about 1 mm 759 mmHg 760 Inhalation at rest 761 760 Exhalation

At 10,000 ftAir--> alveoli --> arteriolar blood --> cells (110) (67) (67) (40)

lungs

venous

arteriolar

cells67

67

40 40 PO2 = 27

PO2 = 27

Page 20: IPHY 3430 2-15-11. Review: During inhalation/exhalation at rest: pressure differential of about 1 mm 759 mmHg 760 Inhalation at rest 761 760 Exhalation

At 20,000 ftAir--> alveoli --> arteriolar blood --> cells (73) (40) (40) (must be >40)

lungs

venous

arteriolar

cells40

40

20 20 PO2 = 20

PO2 = 20

Page 21: IPHY 3430 2-15-11. Review: During inhalation/exhalation at rest: pressure differential of about 1 mm 759 mmHg 760 Inhalation at rest 761 760 Exhalation