9/23- Pulmonary Vascular Diseases Flashcards Preview

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Flashcards in 9/23- Pulmonary Vascular Diseases Deck (54)
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31

T/F: You can get DVT in upper extremity veins?

True!

32

What is seen on CXR for someone with DVT?

- Localized oligemia -> Westermark sign:

- Hampton's hump

- Consolidation (infarct)

- Usual report is "normal"

33

What is seen on EKG for someone with DVT?

- Tachycardia

- Right axis deviation (right sided strain)

- New onset atrial fib

34

What is S1Q3T3?

The classic finding; "not common, but always talked about"

35

What are the diagnostic tests on PE of someone with DVT?

ABG’s: increased A-a difference;

Pa02 may be above 80;

C02 usually decreased

Remember to calculate the A-a diff

- A-a difference is usually increased

- Alveolar gas equation

- [FIO2(PB-PH20) – PaC02/R] – Pa02

- [150-PaC02/0.8] - Pa02

36

What is the Wells Diagnostic Scoring? Considerations?

Predicts clinical likelihood of PE

- Signs/symptoms of DVT (3)

- Another diagnosis less likely than DVT (3)

- HR > 100 (1.5)

- Immobilization/surgery within 4 wks (1.5)

- Previous DVT/PE (1.5)

- Hemotpysis (1)

- Malignancy (active or treated within 6 mo) (1)

Pre test probability: ≤ 2 low; 2-6 Moderate; >6 High

37

What is the diagnostic approach?

- Chest CT with contrast, PE protocol

- Less commonly VQ scan

- Rarely, pulmonary angiogram

- If negative or inconclusive and clinical suspicion present….

-->further diagnostic testing

- Evaluate for DVT or perform other diagnostic test.

38

Pros/cons of diagnosing PE with helical/spiral CT?

Helical/spiral CT:

Advantages

- Specificity

- Availability

- Safety

- Relatively rapid

- Other diagnosis

- Advancing technology

Limitations:

- Expense

- Not portable

- Need contrast

- Poor visualization in some areas

- Contraindication: renal insufficiency/allergy

- Reader expertise 

39

What is a ventilation perfusion scan (VQ scan)?

- Nuclear medicine test to evaluate ventilation (V) and perfusion (Q)

- “Matched” defects

- non-diagnostic, compare to x-ray

- “Unmatched” defects

- suggestive of perfusion abnormality

40

Describe Pulmonary Angiogram

- Process

- Purpose

- Commonality

- Intra-arterial dye

- Directly assesses vasculature

- Rarely used now

41

What do each of these gross pictures show? 

1- Embolus with infarct

2- Saddle embolus

3- Infarct

42

How can DVT be prevented?

Based on level of risk and risk of bleeding

- Low: (under 10% VTE without prophylaxis) early ambulation only

- Moderate: (risk of VTE 40%): most general surgical pts or med pts at bedrest; give LMWH, LDUH, fondaparinux or mechanical if bleeding risk high

- High: orthopedic, major trauma, spinal cord injury; give LMWH, fondaparinux, rivoroxaban, Vit K antagonist; mechanical if bleeding risk high

43

How to treat PE?

Anticoagulation

- Acute

  • Weight-adjusted heparin IV
  • LMWH

- Long term

  • Warfarin
  • Oral factor XA inhibitors
  • LMWH Thrombolysis

Embolectomy

IVC Filter

44

What is HIT?

- Mechanism

- Labs

Heparin Induced Thrombocytopenia

- Immune-mediated drug reaction

- Results in platelet removal -> thrombocytopenia (most common, 90%)

- Results in platelet aggregation and release of procoagulant microparticles (thrombosis)

- Defined by presence of heparin-reactive antibodies to platelet factor 4 (HIT Abs)

45

What are complications of HIT?

- Deep vein thrombosis

- Pulmonary embolism

- Myocardial infarction

- Occlusion of limb arteries (possibly resulting in amputation)

- Cerebrovascular accidents (stroke, TIA)

- Skin necrosis

- End-organ damage (e.g., adrenal, bowel, spleen, gallbladder or hepatic infarction; renal failure)

- Death

46

What is Warfarin?

- Mechanism

- Dynamics/activity

- Metabolism

- ASEs

- Management

- Reversal

- Antagonizes Vitamin K dependent factors (Factors 2, 7, 9, and 10 as well as protein C and protein S)

- Delayed effect based on the shortest 1/2 life (Factor 7: 6 hrs); 18-24 hrs

- Crosses placenta; CONTRAINDICATED in pregnancy

- Numerous drug-drug, drug-disease (liver), and drug-food (Vit K) interactions

- Careful monitoring of INR (standardized msmt of PT); usual targeted range is 2-3

- Reversal with Vitamin K (mild) or FFP

47

What things diminish Warfarin effect? INR level?

INR level will be low

- Inhibits drug absorption: Cholestyramine

- Increases metabolism (enhance p450): Barbiturates, Carbamazepine, Phenytoin, Rifampin

- Vitamin K: foods, esp leafy greens

48

What things enhance Warfarin effect? INR level?

INR will be high

- Displaces from albumin: choral hydrate

- Decreased metabolism (inhibits p450): Amiodarone, clopidogrel, ethanol, fluconazole, fluoxetine, metronidazole, sulfamethoxazole

- Eliminate gut bacteria and decrease K: Broad-spectrum antibiotics

49

What should the duration of therapy be for ?? (HIT?) (PE?)

- 3 months in patients with transient risk factors

- May be life long in patients with recurrent thrombosis or continued risk factors (e.g. malignancy, hypercoagulable state)

50

What is an IVC filter? What is it used to treat?

IVC filter: treatment of PE

- Patients with massive PE who could not tolerate a recurrence

- Patients with contraindications to anticoagulation

- Recommended for repeat PE despite anticoagulation or when anticoagulation is contraindicated

- Filter is a wire apparatus inserted through a catheter in the inferior vena cava to prevent PE

- Filter may be removed

51

What are other therapies for PE?

- Thrombolytic: reserved for patients with massive PE (clinically severe, severe cardio pulmonary compromise, i.e. hemodynamic instability, hypoxemia, RV dysfunction despite resuscitative efforts).

- Embolectomy

52

Summary of Pulmonary HTN

- Various causes and important to classify based on WHO grouping

- Treatment will be guided by etiology

- Progressive shortness of breath, loud P2

- Idiopathic Pulmonary Arterial HTN pathology is medial hypertrophy and intimal fibrosis

- Treatment with pulmonary vasodilators and lung transplant

53

Summary of DVT/PE

- Risk factors of prolonged immobility, hypercoagulable states etc.

- Symptoms of leg swelling, pain in DVT

- Sudden onset SOB+- pleuritic chest pain with hypoxemia in PE

- DVT diagnosed with venous compression ultrasonography

- PE diagnosed by spiral CT or V/Q scan

54

Summary of Pulmonary Vascular Disorders

- Treatment with anticoagulation (UFH, LMWH or Warfarin); Less commonly IVC filter, thrombolysis, embolectomy

- Major complications of heparin is Heparin induced thrombocytopenia

- Major complication of Warfarin is drug-drug interactions