PATHOPHYS Flashcards
What is the alveolar ventilation equation?
PaCO2=K*(VCO2/VA)
Increases in cardiac output __ Do2 linearly
increase
PAO2 does/doesn’t increase DO2 linearly
does not, due to Hb saturation curve
Hb content ___ Do2 linearly
increases
Oxygen content equation
CaO2=(1.39HbSat%)+(.003 PaO2)
Hb saturation curve - a shift to the R indicates a ___ in oxygen affinity
decrease
What are the criteria for allergic bronchopulmonary aspergillosis?
1) Asthma
2) Immediate cutanoue rx to asper
3) IgG to asper
4) IgE>1000
5) Inc IgE to Asper
it is Type III hypersensitivity
Nocturnal asthma is due to
decline of catecholamines/cortisol at night, thus decreasing Beta-2 activity
COPD patient is given 40% oxygen and CO2 goes up - should you stop oxygen therapy?
NO, keep oxygen on until Sat >88%; CO2 increases upon giving oxygen due to haldane, and respiratory muscle fatigue
Hypoxemia of ILD is due to:
V/Q mismatch
ILD cell changes
Type II hypertrophy
Restrictive lung disease CXR pattern
ground glass
A normal BAL shows predominantly these cells
90% macrophages
DLCO up down same in restrictive and why?
Decrease due to increased thickness and decreased surface area
A sandlblaster with FEV < 80%, DLCO less than 80%, what’s going on?
silicosis
Silicosis predisposes you to what disease?
TB
ARDS is characterized by decreases in __
compliance
ARDS systemic inflammation yes or no?
Yes, high
Treatment of ARDS?
Mechanical ventilator 6-8c
DECREASE tidal volume prevents further damage and decreased mortality
What is the only treatment for ARDS associated with lower mortality?
Oxygen
Increase PEEP improves __
oxygenation
Non-survivors prognostic factor -
Cytokines
PEEP helps break this in ARDS
shunt (collapsed alveoli)
Increased hydrostatic pressure over time leads to what kind of effusion and through what
HF -> transudate
Dec pleural pressure causes __ which leads to ___ fluid in pleura
Atelectasis - transudate
Dec oncotic pressure of plasma causes __ leading to a ___ in pleura
Hypoalbuminemia - transudate
Increased oncotic pressure of pleural fluid causes __ which leads to __ in pleura
Inflammation, exudate
What defines the difference between a transudate and exudate?
Protein >.5 exudate, LDH >.6 exudate
What is the most common cause of pleural effusion?
Heart failure
Describe the mechanism of pleural effusion in CHF
Increased fluid due to inflammation causes increased vascular permeability and increased protein concentration
Lymphocytic exudates in pleura DDX
TB or cancer
What determines outcome in patients with pneumonia?
Host response
Bronchial breath sounds are a sign of ___
consolidation
A frequent complication of pneumonia is __
ARDS
What improves first with resolution of pneumonia?
Oxygen, from dec RR
Radiologic resolution of pneumonia lags behind clinical resolution true or false?
True, by several weeks!
Patient deteriorates rapidly with pneumonia and produces a toxin that destroys neutrophils what is the pathogen?
MRSA with PVL toxin
Drug of choice for MRSA?
Vanc
bar exam guy what happened
PE
What is a pathognomonic EKG finding for PE and how common is it
S1Q3T3 only about 10% though
What is a common mutation in healthy people rendering them hyper coagulable and how
Factor V Leiden activates protein C which is a natural anticoagulant; mutations cause hypercoag
What are some other mutations inherited that make you hypercoagulable
Protein C
Protein S
Antithrombin III
Prothrombin deficiency
What are some non-inherited forms of hypercoagulable states?
Estrogen use, hormonal changes, cancer, thrombocytosis
What is the #1 most common cause of hypoxemia in patients?
V/Q mismatch
How does the circulation compensate for V/Q mismatch?
Dec pulmonary vascular resistance compensate
Improve V/Q ratio
Improves overall oxygenation
What is normal A-a gradient for a person?
(Age+4)/4
What is the A-a in a pulmonary embolus?
Normal OR abnormal
CXR for PE?
Usually normal
Pleural effusions do they happen with PE?
Sometimes and are usually small
Westermark’s sign what is it and when?
PE, rarely, it is the absence of any lung signal on CXR
What is a good lab test for PE and what values indicate PE likely?
D-dimer
>500
Farmer falls off tractor what happens, he broke his legs?
Fat embolus
What are the cardinal signs of fat embolus?
AMS
Thrombocytopenia
Petechiae in chest and neck
Management of COPD does NOT include -
Oral systemic glucocorticoids for a patient with mild COPD
Long-term management of oxygen therapy is good or bad for COPD?
real good
What pattern of emphysema is most common in COPD?
Centrilobular (smoking)
In asthma there are __ lymphocytes, while in COPD there are __ lymphocytes
CD4 - asthma
CD8 - COPD
What is the clinical definition of chronic bronchitis?
Production of sputum for 3 months in 2 consecutive years
DLCO - chronic bronchitis, emphysema, asthma?
Chronic bronchitis - normal
asthma - normal
Emphysema - reduced
Features of a benign lung nodule?
Well-defined
No lymphadenopathy or mediastinal masses
No satellite lesions
Calcified nodules, even with layers
Types of benign calcification?
Dense, POPCORN, lamellar
Features of a malignant mass?
Lymph spread, spiculated, cavitation, non-calcified, larger
Know chest CT landmarks
ok
are pH, glucose, cellularity factors that determine exudate vs transudate?
NO, just protein and LDH
