9/23- Pulmonary Vascular Diseases Flashcards Preview

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Flashcards in 9/23- Pulmonary Vascular Diseases Deck (54)
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T/F: You can get DVT in upper extremity veins?



What is seen on CXR for someone with DVT?

- Localized oligemia -> Westermark sign:

- Hampton's hump

- Consolidation (infarct)

- Usual report is "normal"


What is seen on EKG for someone with DVT?

- Tachycardia

- Right axis deviation (right sided strain)

- New onset atrial fib


What is S1Q3T3?

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


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


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


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.


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

Helical/spiral CT:


- Specificity

- Availability

- Safety

- Relatively rapid

- Other diagnosis

- Advancing technology


- Expense

- Not portable

- Need contrast

- Poor visualization in some areas

- Contraindication: renal insufficiency/allergy

- Reader expertise 


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


Describe Pulmonary Angiogram

- Process

- Purpose

- Commonality

- Intra-arterial dye

- Directly assesses vasculature

- Rarely used now


What do each of these gross pictures show? 

1- Embolus with infarct

2- Saddle embolus

3- Infarct


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


How to treat PE?


- Acute

  • Weight-adjusted heparin IV
  • LMWH

- Long term

  • Warfarin
  • Oral factor XA inhibitors
  • LMWH Thrombolysis


IVC Filter


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)


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


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


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


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


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)


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


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


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


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


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