Accuracy of screening for pulmonary embolism in the emergency room

Pertinent historical, clinical, and laboratory findings were recorded for 37 consecutive patients who presented to the emergency room complaining of shortness of breath and chest pain but without evidence of coronary insufficiency, pneumonia, or musculoskeletal injury. 13 had pulmonary embolism suggested by lung scan with or without pulmonary angiogram, or, in 2 cases, by right heart catheterization. As a group, these patients in whom embolism was judged probable approached fairly closely the profiles of previous studies of patients with documented pulmonary emboli. Nonetheless, they differed very little, and in no clinically useful way short of lung scans and invasive studies, from the remaining 24 patients in whom embolism was judged unlikely. In the population served by this emergency room, which has a high morbidity from chest diseases and putative predisposing conditions to pulmonary embolism, screening patients for high and low probability groups for this diagnosis cannot be done on clinical grounds alone. Six-projection ventilation-perfusion lung scanning may be the only acceptable screening examination, and should be available directly from the emergency room in hospitals with an active emergency service.