The clinical impact of risk factor analysis and prophylaxis on pulmonary embolism

Pulmonary emboli cause 50,000 deaths annually despite recognized risk factors and methods of prophylaxis. To determine the impact of risk factor analysis and the use of prophylaxis, a retrospective chart review of patients suffering pulmonary embolism (PE) at Georgetown University Hospital was performed. During a fifty-month period, 25,000 surgical and 36,000 nonsurgical admissions included 171 cases of PE. The incidence of PE among surgical patients was 0.24% (n = 61) and was 0.30% (n = 110) among nonsurgical patients as confirmed in 82% by pulmonary angiography or high-probability ventilation/perfusion scans. PE prophylaxis included pneumatic stockings, low-dose heparin, combination low-dose heparin/stockings, and coumarin. However, prophylactic measures were absent in 23% of the surgical and in all the nonsurgical patients suffering PE. On the basis of established criteria (SVS/ISCVS), 57% of surgical patients suffering PE were considered at high risk as compared with 13% of nonsurgical patients. Conversely, 54% of nonsurgical patients suffering a PE were considered to be at low risk. Standard treatment modalities were instituted after nonfatal PE: anticoagulation (61%), inferior vena cava filter (14%), and anticoagulation/filter (6%). While risk factor analysis identifies high-risk surgical patients, it may be less effective in identifying nonsurgical patients at increased risk for PE.