The Influence of Surgery on Plasminogen Activator Inhibitor

Abstract

In a previous study we have shown that plasminogen activator inhibitor (PAI) decreased in normal healthy volunteers during the day from 6.3±3.1 IU/ml (X±ISD) at 7.15 a.m. to 2.8±2.3 IU/ml at 3 p.m.The aim of the present study was to investigate the effect of major elective abdominal surgery on PAI. Eight patients received 2,500 Xal units of low molecular weight heparin (LogiparinTM) (Gr.l) and 7 patients received 3,500 Xal units of Logiparin (Gr.2). The PAI activity was measured amidolytically according to Chmielewska et al 1983.The plasma level of PAI (IU/ml) was (X±1SD):We found that PAI did not decrease during the day of surgery but the PAI level was significantly higher on the morning after surgery than the previous morning (p ‹ 0.05). The 5th postoperative day the PAI level had returned to pre-operative values in the morning, but did not decrease during the day as seen in normal volunteers. The PAI levels were not influenced by the different doses of heparin.Thus PAI was found to increase postoperatively and the normal decrease in PAI during the day seems to be abolished for at least five days after surgery.