Lung

Question 1

What is an pulmonary embolism?

Answer 1

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

Question 2

What are the common sources for PE?

Answer 2

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

Question 3

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

Answer 3

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

Question 4

What are the risk factors for PE?

Answer 4

• 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

Question 5

What is the pathophysiology of PE?

Answer 5

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

Question 6

What are the clinical symptoms of PE?

Answer 6

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

Question 7

What are the clinical signs of PE?

Answer 7

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

Question 8

What is “Wells criteria”?

Answer 8

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

Question 9

How do you Dx PE?

Answer 9

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

Question 10

How to Tx PE ?

Answer 10

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)

Question 11

What does pulse oximetry?

Answer 11

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

Question 12

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

Answer 12

=/ < 88%

Question 13

What are the use for pulse oximetry?

Answer 13

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

Question 14

What is/does ABG?

Answer 14

Measures partial pressures of O2 and CO2 and pH

Question 15

What are the normal values in ABG?

Answer 15

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

Question 16

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

Answer 16

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.

Question 17

Explain spirometry

Answer 17

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

Question 18

What is the use of spirometry?

Answer 18

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

Question 19

Explain DLco

Answer 19

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.

Question 20

What is the use of DLco

Answer 20

• Distinguish btw asthma, emphysema and COPD

- Monitoring sarcoidosis

Question 21

Causes for low DLco

Answer 21

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

Question 22

Causes for high DLco

Answer 22

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

Question 23

Explain V/Q scan

Answer 23

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

Question 24

What are the use of V/Q scan?

Answer 24

Dx of PE

Question 25

What does methacholine challenge do?

Answer 25

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

Question 26

What is interstitial lung disease?

Answer 26

- 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

Question 27

How is ILD classified

Answer 27

``` 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! ```

Question 28

What are the environmental ILDs?

Answer 28

- Coal workers pneumoconiosis - Silicosis - Asbestosis - Berylliosis

Question 29

What are the ILDs associated w/ granulomas?

Answer 29

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

Question 30

What are the alveolar filling diseases? (ILDs)

Answer 30

- Goodpasture syndrome - Idiopathic pulm. hemosiderosis - Alveolar proteinosis

Question 31

What are the hypersensitivity lung diseases? (ILDs)

Answer 31

- HS pneumonitis | - Eosinophilic pneumonitis

Question 32

What are the drugs that may induce ILDs?

Answer 32

- Amiodarone - Nitrofurantoin - Bleomycin - Phenytoin - Illicit drugs

Question 33

What are examples of miscellaneous ILDs?

Answer 33

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

Question 34

What are the clinical symptoms and signs of ILD?

Answer 34

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

Question 35

How to Dx ILDs?

Answer 35

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