Ventilatory Pump Lecture

Question 1

What constitutes an Airway Clearance problem?

Answer 1

Inability to clear secretions

Question 2

How can you find evidence of retained secretions, infiltrate or consolidation?

Answer 2

Check breath sounds, Chest films, CT, MRI

Question 3

What are some pathologies associated with chronic retained secretions?

Answer 3

CF, bronchiectasis and/or chronic bronchitis

Question 4

What are breath sounds associated with secretions?

Answer 4

course crackles

low pitched wheezes

Question 5

What are breath sounds associated with atelectasis?

Answer 5

fine crackles

Question 6

What are breath sounds associated with airway constrictions?

Answer 6

high pitched wheezes

Question 7

If you have decreased inspiratory or expiratory pressure, what does it mean?

Answer 7

you have decreased ventilatory muscle strength

vent pump problem

Question 8

What is the usual A:P diameter?

Answer 8

1:1 ratio

Question 9

With ventilatory pump issue, what postural assessment might you find?

Answer 9

greater A:P diameter than lateral

Question 10

What happens to the subcostal angle?

Answer 10

it increases from 90*

Question 11

What breathing pattern assessment tells us there is a vent pump issue?

Answer 11

Accessory muscle use at rest

Abnormal/uncoordinated/paradoxical breathing pattern (rest, position change, activity)

Question 12

What tests tell us there is a ventilatory pump issue?

Answer 12

abnormal: PFTs, postural assessment, breathing pattern, decreased MIP or MEP

Question 13

What is normal I:E (inspiration to expiration ratio) at rest?

Answer 13

1:2

Question 14

What is normal I:E (inspiration to expiration ratio) with exercise?

Answer 14

1:1

Question 15

What is a coordinated breathing pattern?

Answer 15

initial thoracic lift through anterior abdominal and lateral costal expansion

Question 16

What is a discoordinated breathing pattern?

Answer 16

Paradoxical thoraco-abdominal motion

Question 17

What happens to I:E with COPD or chronic bronchitis?

Answer 17

1:3 or 1:4

expiration is 3 or 4 times longer than inspiration

Question 18

What is VC?

Answer 18

Vital Capacity

VC = IRV + ERV + VT

Question 19

What is FRC?

Answer 19

functional residual capacity

FRC = RV + ERV

Question 20

What is RV?

Answer 20

Residual volume

volume not available for use (amt increases with pathologies)

Question 21

What PFTs do we use to assess ventilatory mechanics or muscle strength?

Answer 21

Assess maximal inspiratory force (MIF or MIP)

Assess maximal expiratory force (MEF or MEP)

Question 22

What happens to VC during exercise

Answer 22

o Initial increase in volume, then rate
o < 50% of VC: more increased volume
o = 50% of VC: increased elastic load
o > 50% of VC: increased rate

Question 23

What is anatomical dead space?

Answer 23

non-conducting areas (trachea and upper bronchioles)

Question 24

What is physiological dead space?

Answer 24

air gets there, but no perfusion (ex: PE)

Question 25

What drives breathing?

Answer 25

CO2

Question 26

What is VE?

Answer 26

minute ventilation: Volume of air breathed in 1 minute (influenced by C02 levels)

Question 27

What % oxygen, FiO2, is room air?

Answer 27

Room air is 20.93% oxygen (21%) = 0.21

Question 28

What is the partial pressure of oxygen?

Answer 28

760 mmHg = total pressure at sea level

Question 29

What is PO2 at sea level?

Answer 29

PO2 = 760 mmHg x 0.21 = 159.6 mmHg o 760 mmHg = total pressure at sea level o 0.21 = is % of oxygen in room air at sea level

Question 30

CO2 diffuses ____ than O2.

Answer 30

quicker

Question 31

What is the normal pressure in the alveoli?

Answer 31

100-110 mmHg

Question 32

PAO2 formula

Answer 32

PAO2 = (713 mmHg) (FiO2) – 40 mmHg | FiO2 with RA = 0.21; can plug in values for supplemental oxygen

Question 33

For every 10% increase, PaCO2 should go up by

Answer 33

50 mmHg

Question 34

What does Ventilation- Perfusion (V/Q) indicate?

Answer 34

matching of blood flow to ventilation

Question 35

What is ideal Ventilation- Perfusion (V/Q)?

Answer 35

ideally ~1.0 ratio (mid lung zones)

Question 36

What happens at lung base and lung apex to Ventilation- Perfusion (V/Q)?

Answer 36

Lung base: generally overperfused (ratio < 1.0) | Lung apex: generally underperfused (ratio > 1.0)

Question 37

Ventilation- Perfusion (V/Q) is ________-dependent.

Answer 37

GRAVITY

Question 38

What causes decreased accuracy of Sp02?

Answer 38

o Decreased blood flow (Raynaud’s or poor peripheral blood flow) o Mobility or when SpO2 70-80% o Severe anemia (not always) o Dark pigmented skin or nail polish

Question 39

When PaO2 = 60, what happens to SpO2?

Answer 39

SpO2 = 90 | point at which oxygen starts dissociating faster from HgB