Abstract
It is known that patients who are undergoing major orthopaedic operations of the lower legs (fractures, total hip and knee arthroplasty) belong to a high-risk group, for the development of thromboembolic events.
20–40% of the patients develop deep vein thrombosis (DVT) of the calf and 2–4% fatal pulmonary embolism.
These patients may have remarkable activation of the coagulation system, which is important for the development of deep vein thrombosis of the lower legs.
Purpose: The aim of the study is to evaluate the activation of selected blood coagulation parameters, during the preoperative and postoperative period, in patients undergoing high risk of orthopaedic operation of lower limbs.
The exact estimation of these factors is necessary, so that these patients receive the suitable prophylactic antithrombotic therapy,
Patients and methods: We studied 24 patients, 16 women and 8 men, between 23–84 years old, 12 with femur fracture, 8 with total knee replacement and 4 with total hip replacement surgery.
All patients had normal renal function, and the platelets, count, the PT and aPTT were in a normal range.
The patients were hospitalized for 7 days and then they were observed as outpatients for the possibility of developing deep vein thrombosis and for a 4 weeks period.
All patients received a combination of LMWH and graduated compression elastic stockings as a prophylaxis against DVT.
Plasma concentration of Di-dimers and Thrombin -Antithrombin complex (TAT) were measured preoperatively and the second, the fourth and the sixth day postoperatively.
Di-dimers plasma concentration were measured by automated analyzer (VidasBiomerieux) and TAT plasma concentration were measured by an enzyme-linked microimmunoabsorbent assay (microelisa Dade-Berhing)
Results: Preoperative TAT concentration in patients with femur fracture were high. Postoperatively decreased with the major decreasement on the second day (p< 0.039). Till the 6th postoperative day TAT concentration remained above normal range. Di-dimers plasma concentrations were high preoperatively and remained also high postoperatively, without significant statistical difference.
In patients with total hip and knee arthroplasty TAT plasma concentration increased significantly the 12nd postoperative, day, decreased the 4th postoperative day and then increased again (p< 0.01). Di-dimers plasma concentration increased significantly the 2nd postoperative day and then decreased (p< 0,03).
Until the 6th postoperative day Di-dimcrs concentration remained above normal range. Patients with fractures had higher TAT levels preoperatively than patients with total hip and knee arthroplasty. (p< 0.027)
Conclusions: All patients with major orthopaedic surgery of lower limbs have shown significant activation of the coagulation system postoperatively. Patients with fractures present significant activation of the coagulation system post and preoperatively. So it may be necessary in patients with fractures, to start anticoagulation prophylaxis against DVT preoperatively, and the last dose of LMWH must be given 12 hours before the operation.
The abstracts were prepared by Eleni Koutsoukou. Correspondence should be addressed to him at the Hellenic Association of Orthopaedic Surgery and Traumatology (HAOST), 20, A. Fleming str, 15123 Marousi, Athens, Greece.
