We compared twenty-five total hip-arthroplasty patients with twenty-five
patients who underwent other operations on the lower extremity, with regard
to evidence of pulmonary embolism as determined preoperatively and
postoperatively from lung perfusion scans, ventilation scans, and pulmonary
angiography. Blood gases and serum enzymes also were studied. The over-all
incidence of pulmonary embolism was 6 per cent, despite the absence of
clinical evidence of that complication. Abnormalities in scans and blood
studies were common preoperatively, so that the diagnosis often depended on
the detection of additional abnormalities postoperatively.