Respiratory pathophysiology Flashcards

1
Q

Are there sympathetic nerve endings in airway smooth muscle?

A

No, but beta -2 receptors are well represented.

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

What are the beta-2 receptors in the airway smooth muscle activated by?

A

catecholamines circulating in the systemic circulation

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

The beta -2 receptors in the airway smooth muscle is coupled to what proteins?

A

Gs protein

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

activation of the B2 receptors turns on the Gs protein, and this activates what?

A

adenylate cyclase

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

what does adenylate cyclase activate?

A

cAMP

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

What type of messenger is cAMP?

A

2nd messenger

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

along with protein kinase A, cAMP reduces what?

A

Ca+2 release from the sarcoplasmic reticulum

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

What does a reduction in Ca+2 from the SR ultimately cause?

A

reduction in muscle contraction and promotion of bronchodilation

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

when is the bronchodilation pathway by catecholamines turned off?

A

when phosphodiesterase 3 deactivates cAMP by converting it to AMP

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

What does NO do to smooth muscle?

A

it is a potent smooth muscle relaxant

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

Phospholipase C
Leukotrienes
Inositol triphosphate
These are all chemicals that do what to the airway?

A

increased airway resistance

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

Beta 2 agonists MOA?

A

B2 stimulation which increases cAMP and causes a decrease in Ca+2 (leading to bronchodilation)

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

name some Beta 2 agonists?

A

albuterol
salmeterol
metaproterenol

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

Anticholinergics MOA?

A

M3 antagonism leading to decreased IP3 which causes decreased Ca+2 (bronchodilation)

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

Name some anticholinergics?

A

atropine
glycopyrrolate
ipratropium

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

Corticosteroids (inhaled) MOA?

A

stimulates intracellular steroid receptors and regulates inflammatory protein synthesis which causes a decrease in airway inflammation and a decrease in airway hyper responsiveness

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

Cromolyn MOA?

A

Stabilizes mast cell membranes which decreases mediator release and provides prophylaxis for 1-2 hours

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

Leukotriene Modifiers MOA?

A

Inhibits 5 lipoxygenase enzyme which decreases leukotriene synthesis

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

Examples of Leukotriene modifiers?

A

zileuton
Montelukast
pranlukast
zafirlukast

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

Methylaxanthines MOA?

A

Inhibits phosphodiesterase leading to a decrease in cAMP

Releases endogenous catecholamines

Inhibits adenosine receptors

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

What volumes do pulmonary function tests measure?

A

static lung volumes

dynamic lung volumes

diffusing capacity

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

What is static lung volume?

A

how much the air the lungs can hold at a single point in time

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

what is dynamic lung volumes?

A

how quickly air can be moved in and out of the lungs over time

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

what is diffusing capacity?

A

How well the lungs can transfer gas across the alveolocapillary membrane

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

What are the static lung volumes?

A

How much air the lungs can hold at a single point in time

TLC
FRC
IRV
ERV
RV
IC
Vt
VC
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
26
Q

Which lung volumes provide an assessment of airway resistance and lung recoil?

A

dynamic lung volumes

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
27
Q

What is FEV1?

A

Forced expiratory volume in 1 second.

volume of air that can be exhaled in one second.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
28
Q

What is the normal value for FEV1

A

> 80% predicted value

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
29
Q

Which dynamic lung volumes are effort dependent?

A

FEV1

FVC

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
30
Q

This dynamic volume takes age into account and it declines with age?

A

FEV1

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
31
Q

What is forced vital capacity (FVC)?

A

Volume of air that can be exhaled after a deep inhalation

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
32
Q

What is the normal value of FVC for male and female?

A
Male = 4.8 L 
Female = 3.7 L
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
33
Q

What is the normal value of FEVI to FVC?

A

75 - 80%

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
34
Q

Which dynamic volume measures airflow in the middle of expiration?

A

Forced expiratory flow at 25-75% vital capacity

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
35
Q

Which pulmonary function test is the best test of airflow in the small airways?

A

Forced expiratory flow at 25-75% vital capacity

36
Q

What is a normal value for forced expiratory flow at 25-75% vital capacity?

A

100 +/- 25% predicted value

37
Q

What is Maximum voluntary ventilation (MVV)?

A

Maximum amount of air that can be inhaled and exhaled over 1 minute

38
Q

which pulmonary function test is the best test of endurance?

A

MVV

39
Q

What is the normal value of MVV for males and females?

A
Males = 140-180 L 
Females = 80-120 L
40
Q

What is the abbreviation for Diffusing capacity for carbon monoxide?

A

DLCO or Dlco

41
Q

Which test tests the lung’s ability to exchange gas?

A

Diffusing capacity for carbon monoxide test

42
Q

Volume of carbon monoxide that can transverse the aleveolarcapillary membrane per a given alveolar partial pressure of CO describes?

A

Diffusing capacity for carbon monoxide

43
Q

What do flow volume loops allow you to do?

A

differentiate between obstructive and restrictive respiratory disease

44
Q

On a flow-volume loop between what two points does inhalation occur?

A

inhalation occurs between residual volume and lung capacity

45
Q

on a flow volume loop where is flow zero?

A

flow is zero at the line that traverses the loop which is also at end inspiration.

46
Q

When does flow occur on a flow volume loop?

A

flow occurs at inspiration and expiration

47
Q

on a flow volume loop in what direction does volume become more positive?

A

volume becomes more positive from right to left

48
Q

Why does the flow volume loop never get to zero?

A

Residual volume is greater than zero, so the loop never gets to zero (the x axis)

49
Q

What is the max volume the lungs can hold on the flow volume loop (and real life)?

A

Total lung capacity

50
Q

What lung volume represents the width of the flow volume loop (x axis)

A

Vital capacity

51
Q

Factors that have NOT been shown to increase the risk of postoperative pulmonary complications for non thoracic surgery are? (3)

A

mild / moderate asthma
arterial blood gas analysis
pulmonary function testing

52
Q

What are the is the best way to reverse anesthesia induced atelectasis?

A

Alveolar recruitment maneuvers (ARM’s)

This includes increasing peak airway pressure to 30 cm H20 for initial reopening, and increasing the PIP to 40 cm H20 for eight seconds which appears to reverse anesthesia-induced atelectasis almost completely

53
Q

Does the application of PEEP reverse atelectasis?

A

Yes, but only partially

54
Q

When should you apply PEEP to reverse atelectasis?

A

only after ARM have been used in an effort to prevent open airways from collapsing again, then apply PEEP

55
Q

What can help prevent atelectasis that is not ARM or PEEP?

A

Mixing air with oxygen also helps prevent atelectasis

56
Q

Lower than normal values for DLCO tell you what?

A

lower values correlate with a significant reduction in diffusing capacity

57
Q

Does asthma affect tests of gas exchange such as DLCO?

A

NO, asthma affects airway diameter, but not alveolocapillary interface itself. This would affect tests of pulmonary mechanics (FEV1, MMF, etc), but not DLCO.

58
Q

Explain the pathophysiology of chronic bronchitis?

A

Caused by inflammation and mucus production that reduces airway diameter

59
Q

Explain the pathophysiology of emphysema?

A

caused by a reduction in the surface area of the alveolocapillary interface and loss of elastic recoil

60
Q

Who are the pink puffers?

A

patient with emphysema

61
Q

Who are the blue bloaters?

A

patient with chronic bronchitis

62
Q

Tell me about the blood gases/labs of a person with chronic bronchitis?

A

Chronically low Pa02
They tend to retain CO2
They have polycythemia as their RBC have increased to try and compensate for the chronically low PaCO2

63
Q

Tell me about the blood gases/labs of a person with emphysema?

A

Generally has a normal (or slightly reduced) Pa02. The PaCO2 is usually normal or decreased due to hyperventilation.

64
Q

As a result of pulmonary hypertension the patient with chronic bronchitis may have this complication?

A

Cor Pulmonale

65
Q

If a patient has Cor pulmonale then you want to avoid any anesthetic management that would increase PVR, this would include avoiding what?

A

hypoxia

acidosis

hypercarbia (any drug that causes respiratory depression can cause hypercarbia)

hypothermia

nitrous oxide

vasoconstrictors

conditions that increase SNS tone

ketamine (maybe)

66
Q

If you have a fixed PVR what can cause profound hypotension?

A

A decrease in SVR

67
Q

Cor pulmonale is right sided heart failure that results from pulmonary hypertension. This creates a back pressure on the venous circulation that leads to?

A

jugular venous distension

hepatomegaly

lower extremity edema

68
Q

Is increased PAOP consistent with RV failure?

A

NO, it is consistent with LV failure

69
Q

If an area is ventilated but not perfused this increases what?

A

dead space

70
Q

If an area is perfused but not ventilated this increases what?

A

shunt

71
Q

If a patient has a pulmonary embolism will their EtCO2 increase or decrease?

A

Decrease (because it is diluted from a mixture of gas from perfused alveoli and alveoli lacking perfusion)

72
Q

Why do you apply positive end-expiratory pressure for a patient who has just aspirated gastric contents?

A

Atelectasis increases pulmonary shunt, PEEP is indicated to reduce shunt

(hypoxemia is the hallmark sign of aspiration pneumonitis)

73
Q

What drug reduces free radical production, inhibits neutrophil chemotaxis, minimizes reperfusion injury, and improves outcomes in patients with aspiration pneumonitis?

A

Lidocaine

74
Q

What is the best ventilatory strategy for restrictive lung diseases?

A

You want to reduce the risk of barotrauma, you accomplish this with small tidal volumes (6ml/kg IBW) and faster respiratory rate (14-18).
Maintain PIP of less than 30 cm H20.

75
Q

What are the five causes of hypoxemia?

A
high altitude
hypoventilation 
diffusion defect
V/Q mismatch
Right to left shunt
76
Q

High-altitude:

A-a gradient?
02 helpful?
Examples?

A

Normal

Yes

low barometric pressure

77
Q

Hypoventilation:

A-a gradient?
02 helpful?
Examples?

A

normal

yes

low PA02, opioid overdose

78
Q

Diffusion defect:

A-a gradient?
02 helpful?
Examples?

A

Increased

Yes

Pulmonary fibrosis,

79
Q

V/Q mismatch:

A-a gradient?
02 helpful?
Examples?

A

increased

yes

dead space, shunt

80
Q

Right to left shunt:

A-a gradient?
02 helpful?
Examples?

A

increased

no (if shunt > apprx. 30%)

VSD, TOF, Eisenmenger syndrome

81
Q

Negative pressure pulmonary edema is an example of which type of restrictive lung dz?

A

acute intrinsic

82
Q

example of chronic intrinsic restrictive lung dz?

A

pulmonary fibrosis

83
Q

What percentage of cisatracurium and atracurium are metabolized by Hofmann elimination?

A

100% of Nimbex

33% atracurium

84
Q

What effect does acidosis have on NMB?

A

Acidosis impairs the ability of the body’s enzymatic systems to function properly.

Acidosis perpetuates NMB and decreases the efficacy of anticholinesterase.

85
Q

Hypoxemia during OLV is the result of what?

A

intrapulmonary shunt

86
Q

Strategies for reversing hypoxemia during OLV?

A

Increase FI02 100%

Check DLT position with FOB

Apply CPAP 10 H20 to the non-dependent lung

Apply PEEP 5-10 cm H20 to the dependent lung

Ligate or clamp the pulmonary artery or the non-dependent lung (not always possible)

Resume two-lung ventilation

87
Q

EtCO2 capnography is typically a reliable indicator of Tracheal intubation but what times can it give you a false-negative result?

A

cardiac arrest
severe bronchospasm
complete ETT obstruction
equipment malfunction