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Flashcards in Lung Deck (35):

What is an pulmonary embolism?

The condition one are in, when a thrombus in another region of the body embolizes to the pulmonary vasculature tree via the RV ang pulm. artery


What are the common sources for PE?

1) Lower extremity
- most common
- above the knee(iliofemoral) / deep veins of pelvis/ calf vein
2) Upper extremity
- rare, seen in Iv drug abusers


What can be said of DVT + PE in the indication for Tx?

They are one continuum of a disease. Dx of either one is indication for Tx.


What are the risk factors for PE?

- Age >60
- Malignancy
- Prior history of DVT/PE
- Hereditary hypercoagulable state: 1) Factor v Leiden, protein C & S def. 2) Antithrombin 3 def.
- Prolonged immibolozation/long distance travel
- Cardiac disease
- Obesity
- Nephrotic syndrome
- Major surgery
- Major trauma
- Pregnancy, estrogen use


What is the pathophysiology of PE?

1) Emboli block pulm. vasculature 2) Increased resistance, increased pulm. artery and RV pressure 3) Dead space leads to hypoxemia + hypocarbia 4) tachypnea/dyspnea


What are the clinical symptoms of PE?

- Dyspnea 73%
- Pleuritic chest pain 66%
- Cough 37%
- Hemoptysis 13%
- Syncope in large PE
- Decreased general condition


What are the clinical signs of PE?

- Tachypnea
- Rales
- Tachycardia
- S4
- Increased P2(?)
- Shock w/ circulatory collapse
- Other: lowgrade fever, decreased breath sounds, dullness on percussion


What is "Wells criteria"?

A scoring system that takes into account and helps guide the work- up of PE


How do you Dx PE?

1) ABG: PaO2 & PaCO2 are decreased, pH is high (resp.alkalosis)
2) CXR: usually normal- used for exclusion, pleural effusion, atelectasis, Hampton hump, Westermark
3) Venous duplex US of lower extremities
4) CTA: good sens & spec. Test of choice!
5) Pulm. angiography: gold standard - excludes
6) D-dimer: if normal, PE is unlikely


How to Tx PE ?

1) O2 supplement, may require intubation
2) Acute anticoagulation: bolus of LMWH, do not wait for confirmation of DX! Continous infusion for 5-10 days. Goal aPTT of 1,5-2,5
3) Oral anticoagulants: Warfarin or novel anticoagulant (e.g. rivaroxaban)
4) Thrombolytic: streptokinase, tPA, for massive PE
5) IVC filter placement
6) Surgical thrombectomy: hemodynamically compromised, large proximal thrombus (saddle)


What does pulse oximetry?

Measures % of oxygenated Hb. Follows a sigmoid curve in relationship to partial pressure oxygen in the arterial blood.


What is the O2 % established criterion for receiving home oxygen?

=/ < 88%


What are the use for pulse oximetry?

When pulm. disease is suspected. Assessing patients w/ dyspnea(chronic or acute). Useful as screening test.


What is/does ABG?

Measures partial pressures of O2 and CO2 and pH


What are the normal values in ABG?

pH= 7,35-7,45
PaO2= decreases w/ age but 90 is normal in 20y/old
PaCO2= 35-45


In ABG, for every 10mmHg increase/decrease in PaCO2..

The pH increase/decrease by 0,08. If change is the same way as PaCO2, the patient have metabolic primary disease. If the opposite direction, disease is respiratory.


Explain spirometry

Patient exhales as rapidly & forcibly as possible (max inspiration). Spirometer plots the change in lung volume against time.


What is the use of spirometry?

- Distinguish obstructive from restrictive disease
- Assessing degree of functional impairment
- Monitoring effectiveness of Tx
- May detect resp. impairment in asymptomatic patient


Explain DLco

Patient breathes in a small, specific amount of CO, and the amount transferred from alveolar air to pulmonary capillary blood is measured. CO is a diffusion limited gas so other variables are eliminated.


What is the use of DLco

- Distinguish btw asthma, emphysema and COPD
- Monitoring sarcoidosis


Causes for low DLco

- Emphysema
- Sarcoidosis
- Interstitial fibrosis
- Pulmonary vascular disase (PE)
- Anemia, due to decreased CO binding to Hb


Causes for high DLco

- Asthma
- Obesity
- Intracardiac left to right shunt
- Exercise
- Pulm. hemorrhage (alveolar RBC bind w/ CO)


Explain V/Q scan

Compares degree of ventilation to perfusion, exact match is V/Q=1, but normal ratio is 0,8 (physiologic shunting)


What are the use of V/Q scan?

Dx of PE


What does methacholine challenge do?

Assess degree of airway hyperactivity. Used for suspected asthma(sensitive in mild form) and COPD.


What is interstitial lung disease?

- Inflammatory process involving the alveolar wall
- Resulting in widespread fibroelastic proliferation and collagen deposits
- Can lead to irreversible fibrosis, distortion of lung architecture and impaired gas exchange


How is ILD classified

Based on pathologic & clinical characteristics
1) Environmental
2) Alveolar filling disease
3) ILD associated w/ granulomas
4) Hypersensitivity lung disease
5) Drug induced
6) Miscellaneous
Over 100 causes have been identified!


What are the environmental ILDs?

- Coal workers pneumoconiosis
- Silicosis
- Asbestosis
- Berylliosis


What are the ILDs associated w/ granulomas?

- Sarcoidosis
- Histiocytosis X
- Wegener granulomatosis
- Churg-Strauss syndrome


What are the alveolar filling diseases? (ILDs)

- Goodpasture syndrome
- Idiopathic pulm. hemosiderosis
- Alveolar proteinosis


What are the hypersensitivity lung diseases? (ILDs)

- HS pneumonitis
- Eosinophilic pneumonitis


What are the drugs that may induce ILDs?

- Amiodarone
- Nitrofurantoin
- Bleomycin
- Phenytoin
- Illicit drugs


What are examples of miscellaneous ILDs?

- Idiopathic pulm. fibrosis
- Cryptogenic organizing pneumonia (COP)
- ILDs associated w/ connective tissue disease: RA, scleroderma, SLE, mixed CTD
- Radiation pneumonitis


What are the clinical symptoms and signs of ILD?

- Sypmtoms: dyspnea(exertion at first), nonproductive cough, fatigue, other secondary (CTD)
- Signs: rales at base, digital clubbing, pulm. HT, cyanosis (advanced)


How to Dx ILDs?

- CXR: diffuse changes, reticular, reticunodular, ground glass, honeycombing
- CT: high resolution!
- PFT: restrictive pattern FEV1/FVC ratio increase
- Tissue biopsy
- Urinalysis ( Goodpasture, Wegener)