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
- 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
- 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?
- 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?
PaO2= decreases w/ age but 90 is normal in 20y/old
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.
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
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
- Interstitial fibrosis
- Pulmonary vascular disase (PE)
- Anemia, due to decreased CO binding to Hb
Causes for high DLco
- Intracardiac left to right shunt
- 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
2) Alveolar filling disease
3) ILD associated w/ granulomas
4) Hypersensitivity lung disease
5) Drug induced
Over 100 causes have been identified!
What are the environmental ILDs?
- Coal workers pneumoconiosis
What are the ILDs associated w/ granulomas?
- 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?
- 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)