Clinical And Laboratory Variables In Prediction Of Venous Thrombosis After Elective Gastrointestinal Surgery
Thrombosis and Haemostasis
Thirty-two clinical and laboratory variables were measured In 63 patients prior to elective major gastro-intestinal surgery, who were screened for deep vein thrombosis (DVT) using the 125I-fibrinogen uptake test. Twenty-one patients (33%) developed DVT in the six days following surgery. Five clinical variables were significantly associated with subsequent DVT - age, per cent overweight, varicose veins, female sex (all positive risk) and cigarette-smoking (negative risk). Using clinical
... g clinical variables a high-risk group (> 60% DVT) could be separated from a low- risk group (< 10% DVT). None of 20 laboratory variables was significantly associated with DVT, but several (fibrinogen, factor VIII, plasma viscosity, blood viscosity, and serum fibrin degradation products) were associated with malignancy, infection or jaundice, which limits their usefulness in prediction of DVT in this group of patients. An incidental finding, that postoperative fall in haemoglobin was associated with DVT, suggests that bleeding or haemodilution may promote thrombosis. The clinical index requires validation in a prospective study, but may have practical value in selection of high-risk groups for selective prophylaxis or research studies, particularly in view of its simplicity.