Tissue plasminogen activator concentrations in major abdominal surgery. Relationship to postoperative deep vein thrombosis.

Tissue plasminogen activator (t-PA) antigen concentrations were studied in 47 patients subjected to major abdominal surgery. The 17 patients, which developed postoperative deep vein thrombosis (DVT), diagnosed with the 125I-fibrinogen uptake test, had higher levels preoperatively, and on the sixth postoperative day, when the thrombi had already formed. The reduced fibrinolytic activity in patients with a predisposition to postoperative deep vein thrombosis is thus not related to any t-PA deficiency. The postoperative fibrinolytic shutdown may however partly be due to a drop in t-PA antigen levels, at least in the patients, which developed DVT.