Pulmonary Mechanics

Question 1

Intrapleural and Intrapulmonary mechanics:

the intrapleural space is a potential space found where?

Answer 1

b/t the parietal pleura of chest wall and the visceral pleura covering the lung

Question 2

Intrapleural and Intrapulmonary mechanics:

Is the intrapleural pressure positive or negative?

Answer 2

negative (subatmospheric)

Question 3

Intrapleural and Intrapulmonary mechanics:

why is the intrapleural pressure negative?

Answer 3

b/c the lungs recoil inward and the chest wall recoils outward

Question 4

Intrapleural and Intrapulmonary mechanics:

the inward and outward pressures of the intrapleural space are equal when

Answer 4

at FRC

Question 5

Intrapleural and Intrapulmonary mechanics:

how much pleural fluid is around each lung?

Answer 5

10-20 mL

Question 6

Changes in Intrapleural and intrapulmonary Pressures during normal tidal breathing:
During inspiration does the intrapleural pressure become more negative or positive?

Answer 6

More negative (sub atmospheric)

Question 7

Changes in Intrapleural and intrapulmonary Pressures during normal tidal breathing:
why does air enter the lung?

Answer 7

b/c the intrapulmonary pressures are less than atmospheric pressure

Question 8

Changes in Intrapleural and intrapulmonary Pressures during normal tidal breathing:
Does IntraPULMONARY pressure (which was at 0 at end expiration) become more negative or less negative at the start of inspiration

Answer 8

More negative

Question 9

Changes in Intrapleural and intrapulmonary Pressures during normal tidal breathing:
During expiration does intraPLEURAL pressure become more or less negative

Answer 9

Less negative

Question 10

Changes in Intrapleural and intrapulmonary Pressures during normal tidal breathing:
during expiration does intraPULMONARY pressures become more neg or less neg

Answer 10

less neg (actually become Positive) above atmospheric pressure

Question 11

Changes in Intrapleural and intrapulmonary Pressures during normal tidal breathing:
why is air exhaled?

Answer 11

b/c intraPULMONARY pressures exceeds atmospheric pressure

Question 12

Changes in Intrapleural and intrapulmonary Pressures during normal tidal breathing:
when does intraPULMONARY pressures return to 0

Answer 12

at end-expiration

Question 13

Pulmonary Mechanics: Must knows

what couples the lungs to the chest wall

Answer 13

Pleural membranes

Question 14

Pulmonary Mechanics: Must knows

IntraPLEURAL pressure is always ______ during normal tidal breathing

Answer 14

NEGATIVE (subatmospheric0

Question 15

Pulmonary Mechanics: Must knows

IntraPLEURAL pressure becomes _____ negative during inspiration

Answer 15

MORE negative

Question 16

Pulmonary Mechanics: Must knows

IntraPLEURAL pressure become _____ negative during expiration.

Answer 16

LESS negative (but is always in a negative state)

Question 17

Pulmonary Mechanics: Must knows

intraPULMONARY pressure is _____ during inspiration

Answer 17

NEGATIVE

Question 18

Pulmonary Mechanics: Must knows

Intrapulmonary pressure is ______ during exhalation

Answer 18

POSITIVE

Question 19

Pulmonary Mechanics: Must knows

when is the only 2 times intraPLEURAL pressure can become positive?

Answer 19

forced expiration

expiratory effort against closed glottis (valsalva)