Pulmonary Thromboembolism

Pulmonary thromboembolism means the embo­lization and lodgment of thombi in the pulmo­nary vasculature.

Predisposing factors

• PE refers to obstruction of the pulmonary artery or one of its branches by material (eg, thrombus, tumor, air, or fat ) that originated elsewhere in the body.
• Acute pulmonary embolism (PE) is a common and often fatal disease.
• Unfortunately, the clinical presentation of PE is variable and nonspecific, making accurate diagnosis difficult.
• Mortality can be reduced by prompt diagnosis and therapy.
• Air travel
• preventing pulmonary embolism
• obesity
• Cigarette smoking Oral contraceptives Pregnancy
• Surgery
• Traum
• Antiphospholipid antibody syndrome
• Cancer ‘.
• Systemic
• hypertension
• COPD.

Genetic Factors

• Autosomal dominant gene mutation – factor V Leiden and Prothrombin.

Pathophysiology of Pulmonary Thromboembolism

• Venous thrombi from pelvic and deep leg veins embolize to pulmonary arterial circulation or through patent foramen ovale j ASD to arterial circulation.
• There is increased pulmonary vascular resistance, impaired gas exchange, alveolar hyperventilation, decreased pulmonary compliance.
• Most PE arise from thrombi in the deep venous system of the lower extremities.
• There is right heart failure, decreased LV output, coro­nary artery hypoperfusion, circulatory collapse and death.
• However, they may also originate in the right heart or the pelvic, renal, or upper extremity veins.

Pulmonary Thromboembolism  EPIDEMIOLOGY —

• This study certainly underestimates the true incidence and prevalence of PE, since more than half of all PE are probably undiagnosed.
• preventing pulmonary embolism
• peripheral pulmonary stenosis, pulmonary toilet
• PE was the presumed cause of death in approximately 200,000.
• In a study of more than 42 million deaths that occurred over a 20-year duration, almost 600,000 patients (approximately 1.5 percent) were diagnosed with  PE  .

Pulmonary Thromboembolism  Clinical Features

• Embolism may be thrombus, fat embolism, tumor embolism, air embolism, IV drug user substance embolism, amniotic fluid embolism.
• RISK FACTORS —
• pulmonary toilet
• While much of the data related to risk factors are from patients with DVT, a few studies have looked specifically at patients with acute PE
• PE is a common complication of deep vein thrombosis (DVT), occurring in more than 50 percent of cases with phlebographically confirmed DVT

Pulmonary Thromboembolism Symptoms and signs are

• Dyspnoea Tachypnoea Syncope
• peripheral pulmonary stenosis
•  Cyanosis
• Pleuritic pain
• Cough
• Hemoptysis
• Fever
• Chest pain
• Angina pectoris
• Hypotension
• Tachycardia
• Distended neck veins
• Loud P, (loud pulmonary component of second heart sound)
• RV failure.
• Massive PE may be accompanied by acute right ventricular failure, manifested by increased jugular venous pressure,
• The most common symptoms were dyspnea at rest or with exertion
• Circulatory collapse was uncommon
• Symptoms or signs of lower extremity deep venous thrombosis (DVT) were common

Diagnosis of Pulmonary Thromboembolism

• Blood test:

  • Plasma D-dimer enzyme linked immuno sorbent assay (ELISA) level is increased more than 500ngjml.

• ECG:

  • shows sinus tachycardia, AF(atrial fibrillation), S in lead 1, Q in lead 3, inverted T in lead 3.

• Chest X-ray:

  • is normal. There may be focal oligemia (decreased blood supply) called Westermark’s sign, wedge-shaped obesity called Hampton’s Hump, en­larged right descending pulmonary artery called Palla’s sign.

• Venous Doppler

  • shows DVT – Deep vein thrombo­sis.

• Chest CT :

  • Large central PE (pulmonary embolism) seen.
  • Multislice scanners can show pulmonary blood ves­sels obstruction.

• Lung scan:

  • Albuminlabeled radionuclide shows pul­monary capillary blood flow and perfusion defects.

• MRI :

  • MR pulmonary angiography using gadolinium
  • . is non-nephrotoxic, safe, and shows organic as well as functional lung disease.

• Echocardiography :

  • evidence of MI, cardiac tam~ ponade, RV dyskinesia, RVF seen.
  • Pulmonary angiography: may not be required.

Treatment of Pulmonary Thromboembolism

• Thrombolysis  Embolectomy
• preventing pulmonary embolism
• pulmonary catheter
• Anticoagulation with heparin, warfarin Secondary prevention of embolization by infe­rior vena cava filters NSAIDs
• Dobutamine for positive inotropic support and pulmonary vasodilatation
• Volume loading
• Low molecular weight heparin.

• Anticoagulation with heparin and warfarin preventing  pulmonary  embolism

  • Heparin is given along with warfarin for 5 days.
  • preventing pulmonary embolism
  • Dose of heparin is 5-10,000 units IV bolus followed by 1,000 units/hour.
  • Dose of warfarin is 5 mg dail ad’usted accordin -.10 I R.
  • Then he arin discontinued after 5 days and warfarin continued for 6 months to maintain INR of 1.5-3.

• Prevention of Pulmonary Thromboembolism

  • preventing pulmonary embolism
  • Graduated compression stockings.
  • Pneumatic compression devices .
  • prophylaxis with anticoagulants in confined patients.