Random Flashcards
(101 cards)
1
Q
severe hypoxemia with normal CXR and clear lung fields is a hallmark of
A
PE
2
Q
protein C deficiency
A
hypercoaguable state
3
Q
Course of action if pre-test probability of PE is 90% and V/Q scan is low probability for PE
A
start heparin
perform CT angiography
4
Q
decreased FEV1/FVC and decreased TLC
A
mixed obstruction/restriction
5
Q
which endocrine abnormalities are risk factors for obstructive sleep apnea?
A
hypOthyroidism
acromegaly (xs GH)
6
Q
OSA PFTs
A
NORMAL (unless concomitant COPD/morbid obesity…)
7
Q
restrictive pathologies w/ reduced DLC
A
alveolar filling
intersitial
8
Q
increased dead space is NOT a cause of _______, but can lead to _______
A
increased dead space is NOT a cause of HYPOXEMIA, but can lead to HYPERCAPNIA
9
Q
two mechanisms of hypoxemia that improve w/ supplemental O2
A
V/Q mismatch
diffusion abnormality
10
Q
acute respiratory acidosis
A
∆pHa = ∆PaCO2 X .008
11
Q
chronic respiratory acidosis
A
∆pHa = ∆PaCO2 X .003
there is time for the kidney to compensate by holding on to HCO3–, the fall in pHa will be less than during acute respiratory acidosis
12
Q
effect of hyperinflation on diaphragm
A
diaphragm becomes flat and zone of apposition vanishes
- -> less effective P generation, as diaphragm is unable to push out and lift lower rib cage
- -> lower rib cage pulled INWARD (Hoover’s)
13
Q
adenocarcinoma
A
TTF +
Calretinin -
14
Q
mesothelioma
A
TTF -
Calretinin +
15
Q
squamous cell carcinoma
A
TTF -
Calretinin -
16
Q
well’s criteria
A
for PE
only high pre-test/high V/Q –> initiate tx
low pre-test/high V/Q –> too low to initiate tx
17
Q
fat embolus
A
petichae
confusion
18
Q
+ bronchodilator response
A
inc FEV1 by 12% and 200 ml
19
Q
V/Q scan is helpful in which case of pulmonary HTN
A
group 4 (CTEPH)
*only good with HIGH or LOW pre-test probability
20
Q
pleural effusion causes hypoxemia how?
A
no vent but perfusion
–>shunt
SOB, tachypnea, carotids saying breathe
21
Q
ARDS criteria
A
- acute onset (w/i 72 hours)
- predisposing conditions
- diffuse infiltrates on CXR
- severe hypoxemia (PaO2/FiO2 < 300)
22
Q
When inc dead space and inc CO2
- -> hyperventilation
- -> PaCO2?
A
–> PaCO2 should be normal (min vent inc to try to keep PaCO2 at ~40)
23
Q
fx of a solitary nodule that increase probability of a benign process
A
absence of growth for 2 years
presence of calcification
discontinuation of smoking > 15 yrs
younger age
sx (fever…)
24
Q
tx for stage 1 lung cancer (small lesion, <3cm, no nodes/mets)
A
surgery alone
25
tx for locally advanced lung cancer (stage IIIa or some IIIb)
noeoadjuvant chemo and radiotherapy
26
metastatic lung cancer (stage IV)
palliative chemo and/or radiotherapy
27
T/F
OSA is associated w/ wheezing
false
28
T/F
mitral stenosis and CHF cause wheezing
true
29
With ILD, ______ predominates as cause of hypoxemia at rest, but ______ becomes important during exercise.
With ILD, V/Q MISMATCH predominates at rest, but DIFFUSION becomes important during exercise.
30
rales
CXR w/ linear markings
dec FVC and FEV1 but normal ratio
restrictive lung disease
31
CT scan showing lung collapse from pleural effusion compression
best approach
put good lung in dependent position to inc perfusion to it, while dec perfusion to bad lung (reducing shunt).
32
causes of hypercapnia
inc CO2 prod (fever...)
dec minute ventilation
inc dead space
(rapid shallow breathing, response weakness...)
33
hyperinflation _______ the diaphragm
shortens
34
via Starling's law, _____ a muscle should improve its function
via Starling's law, LENGTHENING a muscle should improve its function
35
Supplemental O2 increases PaCO2 mainly by
decreased hypoxic vasoconstriction
and
increased V/Q mismatch
36
Hoover's sign
inward movement of lower ribcage during inspiration
sign of hyperinflation/diaphragmatic shortening
37
TA paradox
as thorax moves outward, abd moves inward during inspiration
via diaphragm dysfunction
38
__________ (IV or oral) improve outcome in AECOPD
SYSTEMIC STEROIDS (IV or oral) improve outcome in AECOPD
39
AECOPD _____ ventilation is indicated
AECOPD NON INVASIVE ventilation is indicated
dec need for intubation
shortens length of stay
decreases risk of aquiring pneumonia
improves survival
40
Decreased PaCO2 (hypocapnia) means...
pt is hyperventilating beyond what would happen solely w/ increased dead space or increased CO2 production
another stimulus to ventilation exists (metabolic acidosis, etc.)
41
Kerley B lines
sign of interstitial pulmonary edema
heart failure
42
Kerley B lines
pleural effusions
cardiomegaly
ARDS
43
Strategy to improving PaO2 in ARDS
1. PEEP --> inc FRC --> improves compliance
2. dec PCWP --> "keep pt dry" (dec fluid movement into alveolar membrane)
* careful not to drop COP too much
44
hyperinflation decreases the ______________ by pulling airways open
hyperinflation decreases the RESISTIVE WORK OF BREATHING by pulling airways open
45
hyperinflation increases the ______________ by pushing the lung onto the flat/noncompliant pat of the compliance (P-V) curve
hyperinflation increases the ELASTIC WORK OF BREATHING by pushing the lung onto the flat/noncompliant pat of the compliance (P-V) curve
46
fever elevates ___ production
fever elevates CO2 production
47
fx inc pulm perfusion post-birth
1. close DA
2. rise in alveolar PO2
3. secrete prostaglandin I2
4. close FO
48
T/F
| arterioles direct blood flow in pulmonary circulation
F
in systemic
49
T/F
| arterioles direct blood flow in pulmonary system
F
in systemic
50
RMV =
TV X respiratory rate.
51
most important m. for expiration during moderate exercise
abdominals
52
a high V/Q means that the alveolar PO2 will be similar to the tracheal PO2
T/F
T
53
a high V/Q in one region of the lung will compensate for a region of low V/Q
F
Hb already saturated
54
Diffusion limitation can cause hypoxemia but not hypercapnia. Why?
CO2 easily diffuses and rapidly moves across thickened membranes
55
Why is orthopnea common in resp m. weakness?
supine position accentuates the paradoxical movement of the diaphragm into the chest during inspiration
56
maximal voluntary ventilation (MVV, L/min)
should be approx 30-40x the FEV1
57
expect reduced MIP if
diaphragm dysfunction
58
characteristic blood gas of hyperventilating pt (exp. ALS (resp. m. weakness))
hypercapnia (often with hypoxemia) and a normal A-aO2 gradient
59
Kussmaul breathing
regular rapid rate with large tidal volume caused by metabolic acidosis
60
pneumotaxic respiratory center
stops inspiration
61
apneustic respiratory center
excitatory effect on DRG/VRG, prolongs ramp action potentials
62
DRG
inspiratory or expiratory neurons?
connects to inspiratory m.
receives input from peripheral cardiopulmonary sensors that regulate respiratory rhythm
63
Upper part of VRG
Botzinger complex
acts as respiratory rhythm generator (pacemaker cells)
64
VRG
inspiratory or expiratory neurons?
both
65
glomus cells
peripheral chemoreceptors
sense low PaO2, high PaCO2 → increase ventilation
(depolarize and signal to DRG to inc vent)
66
central chemoreceptors
medulla
input to DRG
stim via changes in pH (inCSF)
(CO2 crossing into brain from blood)
67
Hering-Breuer reflex
overinflation leads to inspiration
68
j receptors
network of unmyelinated axons in alveoli and small conducting airways
respond to interstitial edema and engorgement of pulmonary capillaries
69
high altitude acute adjustment
hyperventilation (via hypoxia-drive stimulation of peripheral chemoreceptors in aortic and carotid bodies)
70
medullary chemoreceptors respond directly to the presence of
H+
71
OSA
symptoms + AHI ≥ 5/hr
AHI ≥ 15/hr
cessation of airflow for ≥ 10s despite vigorous respiratory effort
72
Obstructive hypopnea
reduction of airflow by ≥ 30%, with ≥ 3% desaturation or arousal from sleep
73
chronic bronchitis dx criteria
cough/sputum most days, minimum of 3 months/2 consecutive years
74
most important effector cell in CF
neutrophils (release elastase that lead to considerable tissue destruction
75
clubbing
CF
76
occupational asthma
usually occurs months-years after onset of exposure
bakers
worsens during week and improves on vacation
77
epithelial erosion (ulceration)
bronchiectasis
78
medication related ILD
amiodarone
methotrexate, bleomycin, busulfan, nitrofurantoin, cyclophosphamide, etc.
79
threshold for starting oxygen
55-60 mmHg
80
excess minute ventilation
hypocapnia
| alkalemia
81
respiratory muscle fatigue
imbalance between elevated WOB and reduced respiratory m. function
manifested by rapid/shallow breathing, results in worsening hypercapnia
can take 24+ hr to resolve
82
can you predict the PaO2 based on a given SaO2?
Not accurately
SaO2 says nothing about ventilation
Hb sat can move L to R depending on pH, PaCo2, temp, 2,3-DPG
83
to know ventilation, measuring ____ is test of choice
to know ventilation, measuring PaCO2 is test of choice
84
indications for non-invasive ventilation
PaCO2 > 45mmHg
| pH < 7.35
85
If pt is already in chronic respiratory acidosis, what needs to bet taken into consideration when setting mech ventilation
Need to estimate PaCO2 pt would typically operate.
If suddenly dec PaCO2 to normal, severe alkalemia may result
86
oxygen toxicity
prolonged delivery of FiO2 above 0.6 (60%) --> acute lung injury
87
cause of hypoxemia in ARDS
SHUNT
88
bacterial empyema
pleural fluid pH level
low (<7.0)
89
tx for pulmonary arterial hypertension (PAH)
| group 1 pulmonary HTN
-anticoagulants
-vasodilators (Ca chan blockers, prostacyclins)
-endothelin antagonists
-PDE-5 inhibitors (cGMP)
guanylate cyclase stimulant (cGMP)
90
Pt has ILD or pulmonary fibrosis
hypoxemia during exercise
Mechanism
Exercise --> transit time of rbc thru alveolar cap DECREASES (CO and pulmonary blood flow increase) --> insufficient time for oxygen to diffuse into cap
Diffusion impairment --> hypoxemia during exercise
91
Pulmonary Artery Hypertension (PAH)
Pre-capillary, PVR=inc, PCWP<15
most severe form
assoc: idiopathic/HIV, cirrhosis - portal HTN, congenital heart disease, drug-induced
92
Pulmonary Venous Hypertension
Post-capillary, PVR=nml, PCWP>15
assoc: L heart disease, systolic or diastolic dysfunction
93
Grp 3 pulm HTN - hypoxic, pulmonary parenchymal
Pre-capillary, PVR=inc, PCWP<15
assoc: Hypoxia (sleep apnea, OHS, high altitude) or Pulmonary Parenchymal (COPD, IPF, etc)
94
Grp 4 pulm HTN – Thromboembolic
Pre-capillary, PVR=inc, PCWP<15
Chronic Thromboembolic Pulmonary Hypertension (CTEPH)
tx: potentially treatable with surgery, endartectomy
95
Grp 5 pulm HTN - others
sarcoid, GSD (Gaucher’s), Hematologic (splenectomy), neurofibromatosis, tumor emboli, chronic renal failure
96
exudate
serum to pleural fluid albumin gradient
< 1.2 g/dL
97
exudate
pleural fluid CHL
> 45 mg/dL
98
status asthmatics
cause of thick, tenacious green sputum
airway Eos
99
mechanism of hypoxemia and hypercapnia during exercise
dec diffusion of O2 and inc CO2 prod during exercise
100
T/F
Excess CO2 production alone is sufficient to cause hypercapnia
alone is insufficient to cause hypercapnia. There must
also be a problem with
ventilation or excess dead space
101
W/ altitude, P___ decreases and hypoxemia worsens
PAO2
PB reduced from 760
