This illustrative slide show explains the process and the mechanics of breathing. Was first presented at 5th of January 2012 in the Tripoli Medical Center meeting hall of the Anesthesia Department.

1. Dr.Hamza Rayes

2. Dr.Hamza Rayes

4. Reasoning
Diagnosis
Management

5. Parietal Pleura Chest Wall
Visceral Pleura
Alveolus

6. Boyle's law:
1
Volume
Pressure

7. Pressure gradient:
Air will flow from a high pressure to low
pressure down it is gradient

8. 0 cm H2O
0 cm H2O
The atmospheric pressure will be considered as Zero for simplification

10. Surface tension:

11. 5
6
5
6
7
7
As the lung enlarges, recoil increases;
As the lung gets smaller, recoil decreases.

12. Outward recoiling force of 5 meaning
The same but in opposite direction
Hence , the negative charge
-5 -5

13. As a result the net force will
sum to Zero. -5
Alveolar elasticity
So no net change -5 -5 exerting a force of
recoil of approximately 5
5
5

14. -5 -5
5
0 cm H2O
5

15. Begining of Inspiration:
Inspiratory Inspiratory
Muscles Muscles
-5 -5
0 cm H2O
When this stretch ability reaches a maximum the inflow of air will eventually increase the
intra alveolar pressure to reach zero equilibrating with atmospheric pressure
Meanwhile, as the alveoli stretches it increases its recoil force from 5 to 8 cmH2O

16. Begining of Inspiration:
Inspiratory Inspiratory
Muscles Muscles
-6 -6
0 cm H2O
When this stretch ability reaches a maximum the inflow of air will eventually increase the
intra alveolar pressure to reach zero equilibrating with atmospheric pressure
Meanwhile, as the alveoli stretches it increases its recoil force from 5 to 8 cmH2O

17. Begining of Inspiration:
Inspiratory Inspiratory
Muscles Muscles
-7 -7
0 cm H2O
When this stretch ability reaches a maximum the inflow of air will eventually increase the
intra alveolar pressure to reach zero equilibrating with atmospheric pressure
Meanwhile, as the alveoli stretches it increases its recoil force from 5 to 8 cmH2O

18. Beginning of Inspiration:
Inspiratory Inspiratory
Muscles Muscles
-8 -8
5
5
Which is obviously higher that the recoil force of 5

19. Beginning of Inspiration:
Inspiratory Inspiratory
Muscles Muscles
-8 -8
5
5
So the alveolus and the small air ways will expand

20. Inspiration
0 cm H2O
Inspiratory Inspiratory
Muscles Muscles
-8 -8
0 cm H2O
-1 cm H2O

21. Inspiration
0 cm H2O
Inspiratory Inspiratory
Muscles Muscles
-8 -8
-1 cm H2O

23. Inspiration
0 cm H2O
Inspiratory Inspiratory
Muscles Muscles
-8 -8
-1 cm H2O
As the air accumulates inside the alveolus the pressure do not increase because
the alveoli stretches and gets bigger

24. Inspiration
0 cm H2O
Inspiratory Inspiratory
Muscles Muscles
-8 -8
-1 cm H2O
As the air accumulates inside the alveolus the pressure do not increase because
the alveoli stretches and gets bigger

25. Inspiration
0 cm H2O
Inspiratory Inspiratory
Muscles Muscles
-8 -8
-1 cm H2O
As the air accumulates inside the alveolus the pressure do not increase because
the alveoli stretches and gets bigger

26. End of Inspiration
0 cm H2O
Inspiratory Inspiratory
Muscles Muscles
-8 -8
0cm H2O
As the air accumulates inside the alveolus the pressure do not increase because
the alveoli stretches and gets bigger

27. This stretchibility can be professionally
designated as Compliance volume/pressure

28. This stretchibility can be professionally
designated as Compliance.
1
Compliance
Lung Recoil

29. Decreased compliance:
Surfactant
Lung Fibrosis
Pulmonary HTN
Laparoscopic Gas
Lithtomyposition

30. This stretchibility can be professionally
designated as Compliance.
1
Compliance
Lung Recoil
+
Surface Tension & Elastic tissue

31. This stretchibility can be professionally
designated as Compliance.
1
Compliance
Lung Recoil
Surfactant
+
-
Surface Tension & Elastic tissue

32. Decreased compliance:
Surfactant
Lung Fibrosis
Pulmonary HTN
Laparoscopic Gas
Lithtomy position

33. Increased compliance:
Emphysema ( elastin)
Asthma ?
Saline
Age
Compliance
1
Lung Recoil
+
Surface Tension & Elastic tissue

35. Lung 0.1 L / cmH20 Chest

36. End of Inspiration
0 cm H2O
Inspiratory Inspiratory
Muscles Muscles
-8 -8
5
0cm H2O
5
When this stretchability reaches a maximum the inflow of air will eventually increase the
intra alveolar pressure to reach zero equilibrating with atmospheric pressure
Meanwhile, as the alveoli stretches it increases its recoil force from 5 to 8 cmH2O

37. End of Inspiration
0 cm H2O
Inspiratory Inspiratory
Muscles Muscles
-8 -8
8
0cm H2O
8
When this stretch ability reaches a maximum the inflow of air will eventually increase the
intra alveolar pressure to reach zero equilibrating with atmospheric pressure
Meanwhile, as the alveoli stretches it increases its recoil force from 5 to 8 cmH2O

38. 0 cm H2O
0 cm H2O

39. 0 cm H2O 0 cm H2O
0 cm H2O 1- cm H2O

40. 0 cm H2O 1 cm H2O
0 cm H2O 0 cm H2O

42. Begining of expiration
0 cm H2O
Relaxation Relaxation
Inspiratory Inspiratory
Muscles Muscles
-8 -8
8
0cm H2O
8
When this stretch ability reaches a maximum the inflow of air will eventually increase the
intra alveolar pressure to reach zero equilibrating with atmospheric pressure
Meanwhile, as the alveoli stretches it increases its recoil force from 5 to 8 cmH2O

43. Begining of expiration
0 cm H2O
Relaxation Relaxation
Inspiratory Inspiratory
Muscles Muscles
-7 -7
8
0cm H2O
8
When this stretch ability reaches a maximum the inflow of air will eventually increase the
intra alveolar pressure to reach zero equilibrating with atmospheric pressure
Meanwhile, as the alveoli stretches it increases its recoil force from 5 to 8 cmH2O

44. Begining of expiration
0 cm H2O
Relaxation Relaxation
Inspiratory Inspiratory
Muscles Muscles
-6 -6
8
0cm H2O
8
When this stretch ability reaches a maximum the inflow of air will eventually increase the
intra alveolar pressure to reach zero equilibrating with atmospheric pressure
Meanwhile, as the alveoli stretches it increases its recoil force from 5 to 8 cmH2O

45. Begining of expiration
0 cm H2O
Relaxation Relaxation
Inspiratory Inspiratory
Muscles Muscles
-5 -5
8
0cm H2O
8
When this stretch ability reaches a maximum the inflow of air will eventually increase the
intra alveolar pressure to reach zero equilibrating with atmospheric pressure
Meanwhile, as the alveoli stretches it increases its recoil force from 5 to 8 cmH2O

46. Begining of expiration
0 cm H2O
Relaxation Relaxation
Inspiratory Inspiratory
Muscles Muscles
-5 -5
5
0cm H2O
5
When this stretch ability reaches a maximum the inflow of air will eventually increase the
intra alveolar pressure to reach zero equilibrating with atmospheric pressure
Meanwhile, as the alveoli stretches it increases its recoil force from 5 to 8 cmH2O

47. Expiration:
0 cm H2O
Relaxation Relaxation
Inspiratory Inspiratory
Muscles Muscles
-5 -5
5
1cm H2O
5
When this stretch ability reaches a maximum the inflow of air will eventually increase the
intra alveolar pressure to reach zero equilibrating with atmospheric pressure
Meanwhile, as the alveoli stretches it increases its recoil force from 5 to 8 cmH2O

48. Expiration:
0 cm H2O
Relaxation Relaxation
Inspiratory Inspiratory
Muscles Muscles
-5 -5
5
1 cm H2O
5
When this stretch ability reaches a maximum the inflow of air will eventually increase the
intra alveolar pressure to reach zero equilibrating with atmospheric pressure
Meanwhile, as the alveoli stretches it increases its recoil force from 5 to 8 cmH2O

49. End of Expiration:
0 cm H2O
Relaxation Relaxation
Inspiratory Inspiratory
Muscles Muscles
-5 -5
5
0cm H2O
5
When this stretch ability reaches a maximum the inflow of air will eventually increase the
intra alveolar pressure to reach zero equilibrating with atmospheric pressure
Meanwhile, as the alveoli stretches it increases its recoil force from 5 to 8 cmH2O

50. 5
5
5
5
5
emphysema
5

51. CPAP PEEP

55. CPAP PEEP

56. Total Ventilation ( Minute Ventilation )
Tidal Volume x Respiratory Rate

57. Approximately the weight of the patient in Pounds
Ex. A 100 pounds patient will have a dead space
of 100 ml
Dead space

63. Alveolar Ventilation:
TV – Dead space x RR

67. Thank you

68. Lange Pulmonary Physiology
Basics of Anesthesia ( Miller )
Board Review Series
http://emsstaff.buncombecounty.org
http://www.uams.edu
http://www.anaesthetist.com
http://www.ncbi.nlm.nih.gov