Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

Anesthesia > Basic Pulmonary Physiology > Flashcards

Basic Pulmonary Physiology Flashcards

1
Q

Muscles of inspiration

A
  • diaphragm (normal inspiration)
  • strap muscles: all scalenes (normal) and SCM (deep inspiration)
  • external intercostals
  • large back muscles, paravertebral muscles, shoulder girdle, and pec muscles (maximal effort)
  • inspiration is an active process
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

Muscles of expiration

A
  • internal intercostals
  • abdominal muscles
  • expiration is a passive process
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

Three “segments” of airways

A
  1. conducting airways: large cartilaginous airways and non-cartilaginous airways including “terminal” bronchioles
  2. Respiratory airways: respiratory bronchioles which have partial gas exchange
  3. Alveoli: clusters, primary site of gas exchange
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

Major contributor of airway resistance

A

Conducting airways

-90% of resistance

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

Reynold’s number

A

(density x velocity x diameter)/(viscosity)

*a number greater than 2,000 means turbulent flow

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

Poiseuille’s Law

A

Describes laminar flow through a tube

Q = (πPr^4)/(8nl)

Q is flow rate, n is viscosity, l is length

So…

P = (8Qnl)/(πr^4)

*eg. airway resistance (P) will increase with decreasing radius, increasing length of airways, and increased viscosity

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

LaPlace’s Law

A

Describes pressure within the alveoli

Pressure = (2 x wall tension x wall thickness) / (radius)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

Pleural pressure is most negative at which lung volume

A

Total Lung Capacity

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

Alveolar Gas Equation

A

PAO2 = FIO2 (PATM – PH2O )– PaCO2 / RQ

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

How is CO2 formed?

A

Carbonic anydrase

H+ + HCO3- H2CO3 H20 + CO2

*BBB is permeable to CO2, but impermeable to H+ and HCO3-

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

Respiratory Quotient

A

RQ = (VCO2) / (VO2)

*normal VCO2 is 200 ml/min, normal VO2 is 250 ml/min, thus normal RQ is 0.8

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

Changes in CO2 responsiveness curves

A

Right shift: describes ventilation depressants (sedative doses of opioids, barbiturates, and benzodiazepines)

Right shift AND slope reduction: very high dose opioids and volatile anesthetics at 1 MAC

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

Pathologies that increase dead space

A
  • decreased CO
  • PE
  • COPD
  • ARDS
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

How much does dead space increase with mechanical ventilation compared to spontaneous ventilation?

A

50%

*normally, 2/3 of TV contributes to ventilation and 1/3 to dead space

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

Three venous systems that contribute to anatomic shunt

A
  • Thebesian veins
  • Bronchiolar veins
  • Pleural veins
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

Normal A-a gradient on room air?

Normal A-a gradient on 100% FiO2?

A

Room air:

17
Q

Normal P/F ratio (paO2/FiO2)

A

> 300

18
Q

Ventilation-Perfusion Index (VQI)

A

VQI = (1-SaO2)/(1-SmvO2)

*essentially shunt fraction
normal VQI = (1-0.99)/(1-0.75) = 0.01/0.25 = 4%

19
Q

Shunt fraction at which increasing FiO2 increases pO2 very little

A

> 30%

*at 40%, almost no effect on pO2 with increased FiO2

20
Q

How do changes in FRC impact shunt?

A
  • Decreases in FRC increases shunt (increase venous admixture)
  • Increases in FRC decreases shunt (increase V/Q ratio)
21
Q

FEF 25%-75%

A
  • effort independent
  • early indicator of obstructive disease
  • indicative of medium-sized airway disease
  • fairly variable within an individual
  • sensitive, not specific
22
Q

Smoking Cessation Effects

A
  • 2 to 4 weeks for ciliary function to return to normal
  • increased sputum production immediately following cessation of smoking
  • reduced carboxyhemoglobin levels within one day
  • full benefit of smoking cessation is realized 8 weeks preop
23
Q

Typical EKG findings in COPD

A

Right heart strain

  • poor R-wave progression
  • enlarged P-waves (P pulmonale)
  • R waves greater than S saves in V1
  • RBBB
  • RAD
  • low voltage (hyperinflation)

*increased incidence of MAT (multifocal atrial tachycardia)

24
Q

Effects of abdominal surgery on pulmonary system

A
  • decreases FRC–>decreasing lung compliance–>increasing shunt and hypoxia
  • FRC decreases due to a 25% loss in ERV (but RV actually increases 10%)
  • TV and TLV each decrease 20%

*effects worst 24 hours post-op and return to normal in 2 weeks

25
Q

Anatomic estimate for level of carina

A

sternal angle

26
Q

Static compliance

A

Volume/Pressure

TV / (plateau pressure - PEEP)

27
Q

Dynamic compliance

A

Volume/Pressure

TV / (peak pressure - PEEP)

28
Q

Resistance flow

A

Peak pressure - plateau pressure

29
Q

Peak pressure vs plateau pressure

A

Peak pressure measures airway compliance (pressure)

Plateau pressure measures alveolar pressure (respiratory system compliance)

Anesthesia (16 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions