Dr.Hamza Rayes

Dr.Hamza Rayes

ReasoningDiagnosisManagement

Parietal Pleura

Visceral Pleura

Chest Wall

Alveolus

Boyle's law:

Volume

Pressure

1

Pressure gradient:

Air will flow from a high pressure to low pressure down it is gradient

The atmospheric pressure will be considered as Zero for simplification

0 cm H2O

0 cm H2O

Surface tension:

5

5

6

6

7

7

As the lung enlarges, recoil increases; As the lung gets smaller, recoil decreases.

-5-5

Outward recoiling force of 5 meaning The same but in opposite directionHence , the negative charge

-5-5 Alveolar elasticity exerting a force of recoil of approximately 5

As a result the net force will sum to Zero. -5 So no net change

5

5

-5-5

5

50 cm H2O

0 cm H2O

-5 -5

When this stretch ability reaches a maximum the inflow of air will eventually increase theintra alveolar pressure to reach zero equilibrating with atmospheric pressure Meanwhile, as the alveoli stretches it increases its recoil force from 5 to 8 cmH2O

Begining of Inspiration:

Inspiratory Muscles

InspiratoryMuscles

0 cm H2O

-6 -6

When this stretch ability reaches a maximum the inflow of air will eventually increase theintra alveolar pressure to reach zero equilibrating with atmospheric pressure Meanwhile, as the alveoli stretches it increases its recoil force from 5 to 8 cmH2O

Begining of Inspiration:

Inspiratory Muscles

InspiratoryMuscles

0 cm H2O

-7 -7

When this stretch ability reaches a maximum the inflow of air will eventually increase theintra alveolar pressure to reach zero equilibrating with atmospheric pressure Meanwhile, as the alveoli stretches it increases its recoil force from 5 to 8 cmH2O

Begining of Inspiration:

Inspiratory Muscles

InspiratoryMuscles

Beginning of Inspiration:

5

5

Inspiratory Muscles

-8

Inspiratory Muscles

-8

Which is obviously higher that the recoil force of 5

Inspiratory Muscles

Inspiratory Muscles

-8 -8

5

5

So the alveolus and the small air ways will expand

Beginning of Inspiration:

Inspiratory Muscles

Inspiratory Muscles

-8 -8

0 cm H2O

0 cm H2O

-1 cm H2O

Inspiration

Inspiratory Muscles

Inspiratory Muscles

-8 -8

0 cm H2O

-1 cm H2O

Inspiration

Inspiratory Muscles

Inspiratory Muscles

-8 -8

0 cm H2O

-1 cm H2O

As the air accumulates inside the alveolus the pressure do not increase because the alveoli stretches and gets bigger

Inspiration

Inspiratory Muscles

Inspiratory Muscles

-8 -8

0 cm H2O

-1 cm H2O

As the air accumulates inside the alveolus the pressure do not increase because the alveoli stretches and gets bigger

Inspiration

Inspiratory Muscles

Inspiratory Muscles

-8 -8

0 cm H2O

-1 cm H2O

As the air accumulates inside the alveolus the pressure do not increase because the alveoli stretches and gets bigger

Inspiration

Inspiratory Muscles

Inspiratory Muscles

-8 -8

0 cm H2O

0cm H2O

As the air accumulates inside the alveolus the pressure do not increase because the alveoli stretches and gets bigger

End of Inspiration

This stretchibility can be professionally designated as Compliance volume/pressure

This stretchibility can be professionally designated as Compliance.

Compliance

Lung Recoil

1

Decreased compliance:

Surfactant

Lung Fibrosis

Pulmonary HTN

Laparoscopic Gas

Lithtomyposition

This stretchibility can be professionally designated as Compliance.

Compliance

Lung Recoil

Surface Tension & Elastic tissue

1

+

This stretchibility can be professionally designated as Compliance.

Compliance

Lung Recoil

Surfactant

Surface Tension & Elastic tissue

1

+-

Decreased compliance:

Surfactant

Lung Fibrosis

Pulmonary HTN

Laparoscopic Gas

Lithtomy position

Increased compliance:

Emphysema ( elastin)

Asthma ?

Saline

Age

Surface Tension & Elastic tissue

Compliance Lung Recoil

1

+

Lung 0.1 L / cmH20 Chest

Inspiratory Muscles

Inspiratory Muscles

-8 -8

0 cm H2O

0cm H2O

When this stretchability reaches a maximum the inflow of air will eventually increase theintra alveolar pressure to reach zero equilibrating with atmospheric pressure Meanwhile, as the alveoli stretches it increases its recoil force from 5 to 8 cmH2O

5

5

End of Inspiration

Inspiratory Muscles

Inspiratory Muscles

-8 -8

0 cm H2O

0cm H2O

When this stretch ability reaches a maximum the inflow of air will eventually increase theintra alveolar pressure to reach zero equilibrating with atmospheric pressure Meanwhile, as the alveoli stretches it increases its recoil force from 5 to 8 cmH2O

8

8

End of Inspiration

0 cm H2O

0 cm H2O

0 cm H2O

0 cm H2O

0 cm H2O

1- cm H2O

0 cm H2O

0 cm H2O

1 cm H2O

0 cm H2O

Relaxation

Inspiratory Muscles

RelaxationInspiratory Muscles

-8 -8

0 cm H2O

0cm H2O

When this stretch ability reaches a maximum the inflow of air will eventually increase theintra alveolar pressure to reach zero equilibrating with atmospheric pressure Meanwhile, as the alveoli stretches it increases its recoil force from 5 to 8 cmH2O

8

8

Begining of expiration

Relaxation

Inspiratory Muscles

RelaxationInspiratory Muscles

-7 -7

0 cm H2O

0cm H2O

When this stretch ability reaches a maximum the inflow of air will eventually increase theintra alveolar pressure to reach zero equilibrating with atmospheric pressure Meanwhile, as the alveoli stretches it increases its recoil force from 5 to 8 cmH2O

8

8

Begining of expiration

Relaxation

Inspiratory Muscles

RelaxationInspiratory Muscles

-6 -6

0 cm H2O

0cm H2O

When this stretch ability reaches a maximum the inflow of air will eventually increase theintra alveolar pressure to reach zero equilibrating with atmospheric pressure Meanwhile, as the alveoli stretches it increases its recoil force from 5 to 8 cmH2O

8

8

Begining of expiration

Relaxation

Inspiratory Muscles

RelaxationInspiratory Muscles

-5 -5

0 cm H2O

0cm H2O

When this stretch ability reaches a maximum the inflow of air will eventually increase theintra alveolar pressure to reach zero equilibrating with atmospheric pressure Meanwhile, as the alveoli stretches it increases its recoil force from 5 to 8 cmH2O

8

8

Begining of expiration

Relaxation

Inspiratory Muscles

RelaxationInspiratory Muscles

-5 -5

0 cm H2O

0cm H2O

When this stretch ability reaches a maximum the inflow of air will eventually increase theintra alveolar pressure to reach zero equilibrating with atmospheric pressure Meanwhile, as the alveoli stretches it increases its recoil force from 5 to 8 cmH2O

5

5

Begining of expiration

Relaxation

Inspiratory Muscles

RelaxationInspiratory Muscles

-5 -5

0 cm H2O

1cm H2O

When this stretch ability reaches a maximum the inflow of air will eventually increase theintra alveolar pressure to reach zero equilibrating with atmospheric pressure Meanwhile, as the alveoli stretches it increases its recoil force from 5 to 8 cmH2O

5

5

Expiration:

Relaxation

Inspiratory Muscles

RelaxationInspiratory Muscles

-5 -5

0 cm H2O

1 cm H2O

When this stretch ability reaches a maximum the inflow of air will eventually increase theintra alveolar pressure to reach zero equilibrating with atmospheric pressure Meanwhile, as the alveoli stretches it increases its recoil force from 5 to 8 cmH2O

5

5

Expiration:

Relaxation

Inspiratory Muscles

RelaxationInspiratory Muscles

-5 -5

0 cm H2O

0cm H2O

When this stretch ability reaches a maximum the inflow of air will eventually increase theintra alveolar pressure to reach zero equilibrating with atmospheric pressure Meanwhile, as the alveoli stretches it increases its recoil force from 5 to 8 cmH2O

5

5

End of Expiration:

emphysema

5

5

5

5

5

5

CPAP PEEP

CPAP PEEP

Total Ventilation ( Minute Ventilation )

Tidal Volume x Respiratory Rate

Dead space

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

of 100 ml

Alveolar Ventilation:

TV – Dead space x RR

Thank you

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