Pulmonary Embolism Flashcards

Flashcards covering key concepts, diagnosis, treatment, and nursing interventions for pulmonary embolism based on the provided review document.

What is a pulmonary embolism (PE)? What can an Emboli be made out of

a life-threatening blockage of blood flow in the lungs. Emboli may be solid (thrombus, fat, tumor cells), liquid (amniotic fluid), or gas (air).

What are the 3 components of Virchow's Triad? + Examples

1) Endothelial injury (trauma, surgery, CVC). 2) Abnormal blood flow (immobility, HF, vascular obstruction). 3) Hypercoagulability (inherited or acquired conditions that increase clotting tendency).

List the key risk factors for PE. - 12

Prolonged immobility (travel, bed rest, post-op);
CVC/PICC lines;
surgery or trauma;
pregnancy;
obesity/sedentary lifestyle;
age (60% of VTE in adults >70);
smoking;
estrogen-containing oral contraceptives;
malignancy (lung, gastric, brain, pancreatic, hematologic, prostate);
hx of VTE or inherited clotting disorders;
long bone fractures (femur);
COVID-19/general infection.

What is the most common type of embolus and where does it originate?

Venous thrombus: a DVT in the leg or pelvic veins.

Fat embolus: cause and classic sign?

Cause: long bone fracture (femur). Sign: petechiae over the chest.

What causes an air embolus?

Scuba diving, rapid ascent, or improper central line management/flushing (CVC/PICC).

Amniotic fluid, septic, and diagnostic-material emboli: what causes each?

Amniotic fluid: obstetric (amniotic fluid/fetal debris enters maternal circulation).
Septic/infected clot: pelvic abscess, infected IV catheter, IV drug use.
Diagnostic material: oil-based contrast/diagnostic agents.

What are the classic/early signs of PE? - 11

Sudden-onset dyspnea;
sharp, stabbing chest pain;
anxiety/apprehension/restlessness;
feeling of impending doom;
tachypnea;
tachycardia and hypotension;
cough + hemoptysis;
diaphoresis;
low-grade fever.

What other exam findings may be present in PE? - 7

Crackles,
pleural friction rub,
S3/S4 heart sound,
syncope,
distended neck veins,
cyanosis,
petechiae over the chest (fat embolism).

How is a mild, stable PE managed?

Mild stable: SpO2 93-94%, dyspnea on exertion. Manage with Lovenox, low-flow O2, and ambulation.

What defines a massive/high-risk PE and how is it managed?

Clot occludes the main pulmonary artery , causing severe hypotension, cardiac arrest risk, RV failure, and shock. Requires ICU, intubation, IV heparin, and possibly thrombolytics.

What is the gold standard test for PE?

CT pulmonary angiography (CTPA).

When is a V/Q scan used instead of CTPA?

When CTPA is contraindicated: pregnancy, renal disease, contrast allergy.

What is the role of the chest X-ray in PE?

Rules out pneumothorax and pneumonia. It does NOT diagnose PE.

What do Doppler ultrasound, echocardiography, and the Wells Criteria each do?

Doppler ultrasound: detects DVT.
Echocardiography: shows right heart strain/clot.
Wells Criteria: scoring tool that estimates PE probability (DVT signs, tachycardia, immobilization, hx VTE, hemoptysis, malignancy).

Which labs are ordered for PE and why?

CBC, CMP; PT, PTT/aPTT, INR; troponin and BNP (rule out cardiac involvement/HF); D-dimer (elevated with active clotting).

Describe the ABG progression in PE.

Respiratory alkalosis (early; hyperventilation blows off CO2) → respiratory acidosis (as shunting/perfusion worsens) → metabolic acidosis (late; lactic acid build-up from tissue hypoxia).

Unfractionated heparin drip: target aPTT, monitoring, duration, antidote?

Initial treatment of choice. Target aPTT 1.5-2.5x control; check aPTT per facility protocol (Q6); continued 5-10 days. Antidote: protamine sulfate.

Why is LMWH (enoxaparin/dalteparin) or fondaparinux preferred over UFH when possible?

Lower risk of bleeding and HIT.

How is warfarin started and what is the antidote?

Started day 1-2 of heparin therapy; overlap until INR 2.0-3.0 for at least 24 hours, then stop heparin. Antidote: vitamin K.

DOACs: examples, key features, antidote? how long

Apixaban, rivaroxaban, dabigatran. Rapid onset, no routine lab monitoring. Antidote: idarucizumab (reverses dabigatran). Oral anticoagulation continues >3 months.

When are fibrinolytics used and what must be screened first?

Reserved for massive PE with shock, hemodynamic collapse, or cardiac arrest.
Screen for recent head trauma, recent surgery, active bleeding. High bleeding risk, so ICU monitoring.
Antidotes: FFP, clotting factors, antifibrinolytics.

What are the bleeding precautions for anticoagulated patients?

Monitor CBC, coagulation panel, platelets daily; assess gums, puncture sites, stool, urine; assess abdomen for distention/firmness; handle gently and protect from falls; keep reversal agents readily available.

Immediate priority interventions for suspected acute PE?-7

1. Activate rapid response;

2. apply high-flow O2;

3. stay with and continuously reassure the patient;

4. raise HOB/high-Fowler's;

5. STAT ABG via respiratory therapy;

6. vital signs;

7. prepare for emergency anticoagulation.

How do you manage hypoxemia in PE?

O2 via NC/mask; mechanical ventilation if severe; continuous pulse oximetry and telemetry; monitor lung sounds, RR, skin color, cap refill, tracheal position.

How is hypotension/shock managed in a patient with PE? Include interventions, medications, and monitoring.

• IV crystalloids initially to support blood pressure

• Monitor hemodynamic status, including CVP and pulmonary artery pressures

• Strict I&O and monitor urine output

• If hypotension persists despite fluids, administer vasopressors such as:

• Inotropes such as may be used to improve cardiac contractility

• ICU-level monitoring for severe PE/shock

What surgical/procedural options exist for PE? 3

Surgical embolectomy; catheter-directed therapy (ultrasound-assisted thrombolysis, mechanical fragmentation); IVC filter.

What is an IVC filter and when is it used?

Traps clots from the lower extremities before they reach the lungs. Used for recurrent VTE despite anticoagulation, high bleeding risk, or patients who cannot tolerate anticoagulants.

List the nursing prevention measures for VTE/PE. -10

1. Early and frequent ambulation;

2. passive/active ROM for immobile patients;

3. SCDs and graduated compression stockings;

4. prophylactic anticoagulants (Lovenox/enoxaparin);

5. reposition Q2;

6. elevate limb ~20° above heart (no pillow under knee);

7. never massage legs;

8. avoid crossing legs and tight/constricting clothing;

9. assess peripheral circulation;

10. smoking cessation.

What travel teaching prevents PE?

Hydrate, change position, walk every 1-2 hours, avoid prolonged sitting.