**12.2.5 Prognosis**

The mortality rate for hospitalized patients > 65 with pulmonary embolism is 21%. If pulmonary embolism is the primary diagnosis, the mortality rate is 13%; if it is a secondary diagnosis, the rate is 31%. Thus, many diseases and medical conditions--including heart failure, chronic obstructive pulmonary disease, cancer, myocardial infarction, stroke, and hip fracture--greatly increase the risk of death among hospitalized patients > 65 with pulmonary embolism. Prognosis is poorest for patients with severe underlying cardiac or pulmonary disease.

In patients > 65 with a pulmonary embolus, the recurrence rate in the first year is 8%, and the 1-year mortality rate is 39% (21% inpatient mortality and an additional 18% mortality during the first year). Elderly patients with deep vein thrombosis but without pulmonary emboli have a 21% mortality rate in the first year.

### **12.2.6 Treatment**

Pulmonary embolectomy is not recommended in the elderly because it has a very low success rate and medical therapy is generally quite effective. These procedures should regularly be found in the armamentarium of geriatritians.

**Heparin** prevents clot formation and extension. As the risk of death from pulmonary embolism is the greatest in the first few hours of development of a clot and since diagnostic test results often are not available for 8 to 12 hours, heparin should be given to patients with a moderate to high clinical probability of pulmonary embolism or deep vein thrombosis until all diagnostic results are available. Low-molecular-weight heparin (LMWH) is preferred to unfractionated heparin. **LMWH** can be given subcutaneously once or twice a day, and laboratory monitoring may not be necessary.

Long-term anticoagulation is begun in the hospital with heparin and is continued after discharge, usually with **warfarin**.

**Thrombolytic (fibrinolytic) therapy** should be considered for patients with deep vein thrombosis involving the iliofemoral system. It is also useful for patients with massive pulmonary embolism who have significant pulmonary hypertension, obstruction of multiple segments of the pulmonary circulation, right ventricular dysfunction, or systemic hypotension.

#### **12.2.7 Prophylaxis**

Prophylaxis reduces the incidence of fatal pulmonary emboli by two thirds in hospitalized patients at risk of developing venous clots. LMWH (eg, enoxaparin 40 mg sc once daily) is as effective and safe as prophylaxis with subcutaneous heparin (5000 IU sc bid or tid) and may reduce drug-induced adverse effects. Postoperative prophylaxis with LMWH (eg, sc q 12 h for up to 14 days) also dramatically reduces the incidence of venous thrombosis after knee or hip replacement and in abdominal surgery (Bottaro et al., 2008). For total hip replacement, some investigators find that 4 to 6 weeks of LMWH postoperatively may be more effective (Kanaan et al., 2007).
