Brainscape's Knowledge GenomeTM

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


See full index

SIU SOM: CRR > pulmonary phys > Flashcards

pulmonary phys Flashcards

1
Q

relationship between lung volume and resistance of extraalveolar and alveolar arteries

A

extraalveolar arteries are exposed to pleural pressure
alveolar arteries are exposed to alveolar pressure
at RV: extraalveolar resistance is at its highest and alveolar resistance is at its lowest
at TLC: vice versa
total pulmonary resistance is lowest at FRC

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

alveolar gas equation (find PAO2)

A

PAO2= PIO2 - (PACO2/R)
normal PIO2 = 150
normal R = .8
PaCO2 = PACO2

if need to calculate PIO2: PIO2 = FIO2 x (PB-PH2O)

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

PAO2 difference

A

used to find V/Q inequality, diffusion limitation, or shunt pathways
normal: 5-10 mmHg
PAO2- PaO2

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

define shunt

A

deoxygenated blood entering the left ventricle

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

how to determine if anatomical shunt

A

administer 100% O2, if PaO2 improves then not due to anatomical shunt

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

AVR

A

alveolar ventilation rate
AVR=(tidal volume-anatomical dead space) x ventilation frequency
norm: 4.2 L/min

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

how can PACO2 be affected

A

inversely proportional to AVR
directly proportional to VCO2 (metabolic production rate of CO2)
norm: 40 mmHg

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

calculating physiologic dead space

A

Bohr equation

dead space/tidal volume = (PaCO2 - PECO2)/PaCO2

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

J receptors

A

juxtacapillary receptors

respond to vascular congestion and by physical presence of the emboli and inflammatory mediator release

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

conditions of metabolic acidosis

A

low pH
primary problem: low H3O-
compensation: lower PaCO2 by hyperventilating

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

conditions of metabolic alkalosis

A

high pH
primary problem: high HCO3-
compensation: increase PaCO2 by hypoventilating

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

conditions of respiratory acidosis

A

low pH
primary problem: high PaCO2
compensation: increase HCO3- in the kidney

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

conditions of respiratory alkalosis

A

high pH
primary problem: low PaCO2
compensation: decrease HCO3- in kidney

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

how to determine chronic respiratory acidosis/alkalosis

A

chronic: 4 mEq/L increase or decrease in plasma HCO3 for each 10 mmHg increase or decrease in PCO2

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

henderson hasselbalch equation for acid-base distrubances

A

pH= pKa + log 10 (HCO3-/.03X PaCO2)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

what two factors reduce compliance in healthy lung

A

lung elastic recoil and surface tension of fluid lining alveoli

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

lateral traction

A

alveoli stretch eachother and counteract recoil

if lateral traction is loss atelectasis can occur

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

O2 capacity

A

amount of O2 in the blood when Hb is 100% saturated
Hb concentration x 1.34 plus dissolved O2
(norm Hb concentration is 13.5)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

O2 content

A

amount of O2 actually in blood

percent of O2 saturation x Hb concentration x 1.34 plus dissolved O2

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

dissolved O2 calculation

A

.003 x PO2

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

what is the Bohr effect in regards to Hb and O2 binding

A

Hb affinity for O2 is inversely related to both acidity and CO2 concentration, as both increase, it loses affinity for O2

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

Ficks law of diffusion equation

A

(A x D)/T= diffusion capacity
where A= area, D= diffusion constant, T= thickness

or

Vgas/(P1xoP2x)=Dlx
where Vgas= rate of gas exchange, and pressure differences across membrane

23
Q

calculating diffusion capacity for CO

A

DLCO = VCO/PACO

bc no CO in the capilaries

24
Q

normal DLCO and levels that indicate a diffusion impariment

A

norm: 21-30

diffusion impairment: 1/3 or less (i.e. 7)

25
Q

PTM

A

transmural pressure

pressure difference across an airway wall at any point in the tracheo-bronchial tree

26
Q

functional residual capacity

A

end of quite expiration
all respiratory muscles are relaxed
tendency of lungs to colapse is balanced by the tendency of chest wall to expand

27
Q

calculating transmural pressure

A

Alveolar pressure - intrapleural pressure = transmural pressure

28
Q

incresing/decreasing transpulmonary pressure has what effect on lung expansion

A

increasing transpulmonary pressure: lung expansion

decreasing transpulmonary pressure: lung collapse

29
Q

transpulmonary pressure at FRC

A

no airmovement so PALV is 0
PTP = PALV - PIP
so: PTP= -PIP
you can messure Pip with esophageal balloon (-5 cmH20)
Pip= -5 cmH2O so PTP = -(-5) = +5 cm H2O
since chest wall and lung recoil are equal and oppostie, chest wall is 2.5 and lung recoil is 2.5

30
Q

Fick’s principle

A

measures cardiac output
Q = VO2/ (CaO2-CvO2)
where: VO2 = rate of O2 uptake, (CaO2-CvO2) = content difference in arteries vs vein

31
Q

regarding lung and chest wall pressures, are negative/positive pressures expanding or collapsing

A

negative lung or chest wall pressure is expanding (lung never negative)
positive lung and chest wall pressure is collapsing

32
Q

how is lung recoil pressure measured

A

intrapleural pressure is measured with an esophageal balloon and in an open system Palv will be 0 so can calculate using PTP=-Pip and PTP will be used for the lung recoil here

33
Q

how is system pressure measured

A

pressure gauge in upper airways with mouth closed (closed system) and respiratory muscles relaxed

34
Q

how is chest wall pressure measured

A

its calculated

system pressure = lung recoil + chest wall pressure

35
Q

condition 1

A

open system –> PALV = 0
holding volume constant with muscles –> cancels affects of chest wall
with esophageal balloon, able to measure PTP which will be -Pip only since Palv = 0

36
Q

condition 2

A

alveoli/airways closed system–> air cannot escape lungs and causes a resistant pressure negating lung recoil
relaxing all muscles: allows chest wall to pull/push
measure the system with pressure gauge
Pip= CW only

37
Q

effects of obstructive vs restrictive on FEV1/FVC

A

FVC (forced vital capactiy)
FEV1 (forced expired volume in first second)
FEV1/FVC decreases in obstructive and either stays the same or increases in restrictive

38
Q

why is rate of air flow only effort dependent at high volumes

A

at low lung volumes, reduced mecahnical thethering cannot oppose tendency toward airway collapse so any effort put into exhaling will be negated

39
Q

PEF

A

peak expiratory flow

40
Q

MIF

A

maximum inspiratory flow

41
Q

what are the two points on the x axis of a flow volume loop

A

TLC (total lung capacity, usually on left side of graph, the larger volume) and RV (residual volume, usually on right side of graph, the smaller volume)

42
Q

EPP

A

equal pressure point
when pressure is less than intraplural pressure therefore collapsible
in healthy individuals this is at the noncollapsible portions of the airways but in patients with COPD this is in the collapsible portions causing collapse and therefore cannot get air out

43
Q

what are the mechanisms of obstruction in a COPD patient

A

decreased airway pressure due to increased lung compliance cannot prevent dynamic compression of lower compressible airways
decreased mechanical tethering between lung tissue which usually tends to keep alveoli and compressible airways stretched open
bronchial narrowing due to bronchitis

44
Q

restrictive diseases

A

cannot get air in

45
Q

obstructive diseases

A

cannot get air out

46
Q

what do peripheral vs central chemoreceptors detect

A

central: CO2
Peripheral: CO2, O2, and pH

47
Q

inspiratory control centers and expiratory control centers

A

inspiratory: dorsal respiratory group and intermediate portion of ventral respiratory group
expiratory: rostral and caudal portions of ventral respiratory group

48
Q

how do central chemoreceptors respond to CO2 levels

A

once acrossed the blood-brain barrier, CO2 is converted into H+ and bicarb, the central chemoreceptors detect the H+ ions and sends signal to medullary respiratory center resulting in pumlonary ventilation

49
Q

pulmonary stretch receptors

A

slowly adapting receptors
lie in smooth muscle of conducting airways
respond to airway stretch, sense lung volume

50
Q

irritant receptors

A

rapidly adapting receptor
lie beneath surface of larger conducting airways
stimulated by histamine, serotonin, prostaglandins liberated during allergy and inflammation
stimulation causes cough, gasping, and prolonged inspiration time

51
Q

C fiber endings

A

pulmonary C fibers
located near alveoli
respond to to mechanical stress

52
Q

juxtapulmoary capillary receptors

A

J receptors
located in airways
respond to inflammation or vascular conjestion

53
Q

proprioreceptors

A

joint, tendon, and muscle spindle receptors

located in chest wall increases motor excitation when movement

SIU SOM: CRR (15 decks)

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