Quiz 4 Flashcards
(113 cards)
1
Q
Specialized test are often standard test performed under special conditions to evauate
A
response to a condition or medication
2
Q
Specialized test can be used in pts who have:
A
- Normal PFTs but have respiratory symptoms
- uncertain results of bronchodilator testing
- used to identify and characterized hyperresponsiveness in airway
- Assess changes of hyperactivity or assess severity of symptoms
- For those at risk of environmental or occupational exposure to antigens
3
Q
What is the Bronchoprovaction challenge aka Bronchial challenge used for?
A
To identify and characterize hyperresponsive in the airways
4
Q
The less gas it takes to evoke a negative response,
A
the more hyperreactive the airway is
5
Q
With this test we provoke bronchospasm in the airways
A
Bronchial challenge
6
Q
Direct stimulus include:(4)
A
- Methacholine
- Histamine
- Prostagladins
- Leukotrienes
7
Q
Indirect Stimulus includes (5)
A
- Mannitol
- Adenosine
- Exercise
- Eucapnic voluntary hyperventilation beta blockers
- Hypertonic saline
8
Q
Direct stimulus work directly on the
A
parasympathetic muscle to cause bronchospam
9
Q
Indirectly stimulus causes ___________________ via intermediary cells
A
bronchoconstriction
10
Q
____________________ and ______________ are chemicals that increase parasympathetic response in bronchial smooth muscle
A
Methocholine and Histamine
11
Q
What uses cold air or room temp gases and causes heat and water loss from the airway?
A
Eucapnic Voluntary Hyperventilation
12
Q
Methacholine is inhaled by the pt, along with increasing doses from
A
0.016 mg/ml to 16 mg/ml, prepaired in two to four fold dilutions
13
Q
Methacholine is used in pts who cannot
A
tolerate repeated spirometry testing
14
Q
When is it considered a positive result in Metha Challenge?
A
When FEV1 is reduced by 20%
(PC20 or proactive concentration)
15
Q
Metha challenge test is considered negative if the
A
dose reaches 16 mg/ml w/o 20% reduction in FEV1
16
Q
_____ pts will experience a change in airway w/ increasing concentrations?
A
ALL
17
Q
A healthy subject will not
A
display a decrease of 20% or more in FEV1
18
Q
What disease process usually drops 20% w/ dose as low as 8 mg/ml or less during metha challenge and why?
A
Asthma b/c they have very sensitive airways
19
Q
What other disease process may usually drop during Metha challenge (3)
A
- COPD
- CF
- Bronchitis
20
Q
What is the test criteria for Methacholine challenge?
A
Pts must be ASYMPTOMATIC
- no coughing or wheezing
- no recent upper or lower respiratory infections
- baseline FEV1 should be normal or at least > 60% predicted
21
Q
What are some contraindications of the Metha challenge?
A
- Myocardial infarction in last 3 months
- Stroke
- Aortic aneurism
- Uncontrolled HTN
- FEV1 < 50% predicted or <1.0L b/c risk that the challenge may leave the individual w/ compromised lung function
22
Q
How long should SABAs be withheld?
A
8hrs
23
Q
How long should LABA’s be withheld
A
48hrs
24
Q
Beta agonist (range)
A
12-24hr
25
Anticholinergics
24hrs
26
Theophyline (range)
12- 24 hrs
27
Extended Theophyline
48 hrs
28
Antihistimines
72 hrs
29
What are the 2 methods of delivery for Metha challenge?
- 5-breath dosimeter (most common)
- 2 min Tidal breathing method
30
For a 5 breath dosimeter method the delivered dose of the methacholine is standardized by using a fixed
number of 5 breaths for each
31
For the 2 minute method, the delivered dose is standardized by using a
fixed length of time
32
What are the 2 **dosing** methods?
- Quadrupling method (4x)
- Doubling method (2x)
33
The highest dose for either test is
16 mg/ml
34
Methacholine is administered sequentially in increasing concentration ranging from
0.016 to 16 mg/ml
35
Methacholine is given via
neb starting with the lowest (most diluted) concentration
36
Doismeter (most common) is delivered in
5 breaths
37
Methacholine is prepared in
5 concentration each dose is 4x larger than the previous
38
Can doismeter be prepared and advance?
Yes, must be stored in fridge. Must be room temperture at the time of use
39
Why is doismeter preferred?
B/c it delivers a consistent volume of drug w/ a fixed volume of aerosol on each breath
40
The pt takes 5 breaths of first concentration through
mouth w/ nose clips on (closed circuit)
41
How should the breaths be during this test?
deep and slow
(RV to IRV) w/ slight breath hold at TLC
42
When should spirometry be repeated? (Range)
30 to 90 seconds after each breath
43
After the test is completed what should be done?
Bronchodilator to reverse bronchospasm
44
If at anytime during testing FEV1 decreases by >20% then the
test is complete
45
What device is used for the 2 minute tidal breathing method?
Small volume neb
46
A _________ should be used on the _____________ limb
filter;
expiratory
47
Output needs to be
0.13 ml/min
48
Pt rebreathes ______________ methacholine solution w/ normal relaxed breaths thru mouth w/ nose clips for 2mins
nebulized
49
The 2 min tidal breathing method dosage starts at
0.031 mg/ml and increases 2x each step until the max is reached of 16.0 mg/ml
50
This test method can also be prepared ahead of time and must be at room temp when used
something to know
51
Why is a filter used on the expiratory side?
To prevent methacholine release in the room
52
If FEV1 decreases 20% or greater it is considered a
positive response (pt airway is hypersensitive)
53
How do you report a decrease of 20% in FEV1 after the first dose?
PC20 at < first dose
54
How do you report no decrease after the last dose
PC20 >16 mg/ml
55
If there is a decrease in FEV1 of 20% (PC20) at low doses of methacholine, there is a
high probability of asthma
56
If FEV1 decrease of less than 20% at 16.0 mg/ml negative results
asthma is unlikely
57
Pts requiring higher doses 8-16 mg/ml often do not
have asthma
58
____________________ challange stimulates bronchoconstriction directly
Histamine
59
Aerosolized histamine extract is similar to
methacholine challenge
60
How is the test performed?
- spirometry is performed
- A concentration of Histamine is administered and the spirometry to get FEV1
61
As long as the pt does not have a decrease in FEV1 of 20% during the Histamine challenge w/ the diluent then......
the test continues
62
Pts breathes in ___ breaths of the 1st concentartion
5
63
For histamine, dosing begins at
**0.03mg/ml** and doubled until reaching the max dose **10mg/ml**
64
What are some of the most common side effects of Histamine?
- flushing
- headache
- sleepy
65
Pt should not have these for 48 hrs b.c it can cause bronchospasms
Antihistamines
66
What is the peak action of histamine
30 sec to 2 min, same as methcholine
67
Exercise challenge is commonly used in pts w/ suspected
Exercise Induced Asthma (EIA)
68
Bronchospasm usually occurs....
during or immediately after vigorous exercise
69
What is bronchospasm usually related to during exercise?
Heat and water loss in the airway due to increased ventilation
70
Candidates for Exercise Testing
- Normal PFTs have SOB on exertion
- Other challenge test such as methacholine or histamine were normal but pt is symptomatic
- Evaluating therapy in a known EIA pt
- Screening pts who may have associated risk if they are asthmatic
71
Would you perform an exercise challenge on an Asymptomatic pt?
No b/c they have no symptoms
72
How long should we wait to perform another exercise challenge? and why?
4hrs; Due to catecholamine release (neurotransmitters such as epinephrine and dopamine) will cause bronchoconstriction to lessen w/ additional testing
73
What is needed before an exercise challenge test?
- History and physical
- EKG
- No bronchodilators prior to test
- FEV1 should be no less than 65%of predicated
- No vigorous exercise for 4hrs prior
- No respiratory infections 3-6 weeks prior
74
Workload should be at
80-90% of max HR for 4 to 6 mins
75
During the exercise test what should be monitored? (4)
- EKG
- HR
- BP
- sats
76
When should you monitored vitals?
1 to 2 mins post exercise
77
When is the exercise challenge test positive?
Decrease of **10 to 15%** of FEV1
78
In a healthy pt exercise will
increase the FEV1.
(if it increases then pt most likely does not have EIA)
79
Eucapnic Voluntary Hyperventilation Testing is similar to
exercise testing, b/c it provokes a bronchospasm due to heat and water loss from the airways
80
EVH usually uses (2)
- cold, dry gas
- CO2 is added to prevent hyperventilation (creating a co2 narcosis)
81
To perform the EVH a mixture of air is passed over a....
heat exchanger or cooling coil to chill air to -10 to -20 degrees Celsius
82
No ___________________ prior to test b/c we are trying to
bronchodilators;
invoke a bronchospasm
83
What is the most common test used for EVH
Cold air method
84
During the EVH test, pt's must rebreathe in gas w/ ______________ respirations.
elevated
85
Pts must ventilate at 60- 85% of their
MVV for 4-6 minutes during the EVH test
86
What is added to prevent hyperventilation during the EVH test?
CO2
87
A decreased FEV1 of ___ % in the EVH test indicates a reactive airway (positive)
10%
88
In a healthy person EVH will usually cause _______________ not a bronchospasm
bronchodilation
89
Some asthmatics will experience an **significant** decrease FEV1 of
20-60%
90
Exhaled Nitric Oxide (ENO) is a method used for assessing
airway inflammation
91
ENO measures
inflammation in the lungs
92
ENO specifically measures
Eosinophilic inflammation
93
Increased eosinophilic is common in what disease process (2)
- Asthma
- COPD
94
What causes a decrease in ENO?
smoking
95
Before an ENO test pt's should not (3)
- smoke
- eat
- drink
(for 1 hr prior)
96
When should the ENO test be performed?
before ALL the other test
97
What should be recorded before the test?
current meds and health status
98
What can decrease inflammation?
Corticosteriods
99
How can ENO be measured? (2)
- Online
- Offline
100
Sample exhaled gas continuously at the mouth is most common. Which ENO measuring method is this?
Online
101
This measures collected gas in an sampling device
Offline
102
For online pt inhales thru
Nitric oxide scrubber.
They exhale to RV, and inspire over 2 to 3 seconds to TLC (slow, even deep breath)
103
To prevent nasal no contamination....
nose clips is needed
104
Exhaled gas with the online method, measuring should be (#)
0.05L/sec
105
We must have at least ___ acceptable test withing ___% of each other then average them
2;
20%
106
How long should you wait in between measurements for online?
30 seconds
107
For offline measuring the pt inhales to
TLC through no scrubber or from a reservoir of no-free gas
108
Where is the sample collected in the offline measurement?
In a ballon
109
How long does analysis take for offline?
12 hr
110
For nasal nitric oxide air is aspirated into
one side of the nose and out the other
111
What is the normal FENO in adults and children
adults 10-35 ppb
children 5-25
112
If levels are elevated above the norms, what does this mean?
Suspected eosinophilic inflammation of the airways or alveolitis
113
Why do changes in Nitric oxide happen quicker than changes in PFTs?
It demonstrates immediate changes in airway inflammation markers
