Low-frequency hemoviscoelastography in monitoring coagulation disorders after abdominal surgery for cancer

Introduction

Venous thromboembolism is of the most common complications in cancer patients and may be due to the hypercoagulable state of malignancy and to its surgical treatment.

Methods

Patients undergoing planned curative open surgery for abdominal cancer received MEDNORD (Ukraine Co. analyzer) analysis (HVG), a viscoelastic test that measures clot formation and includes information on the cellular as well as the plasmatic coagulation system. We examined the efficacy of a variety of coagulation tests. A complete coagulation screen, activated clotting time, thromboelastography (TEG) and haemoviscoelastography (HVG) were performed before surgery, at the end of surgery, and on postoperative days 1, 2, 3, and 7; they were analyzed for the reaction time and the maximal amplitude (MA).

Results

We calculated the elastic shear modulus of standard MA (Gt) and HVG MA (GH), which reflect the total clot strength and procoagulatory protein component, respectively. The difference was an estimate of the platelet component (Gp). There was a 14% perioperative increase of standard MA, corresponding to a 48% increase of Gt (P < 0.05) and an 80 to 86% contribution of the calculated Gp to Gt. We conclude that serial standard thromboelastography and the HVG viscoelastic test may reveal the independent contribution of platelets and procoagulatory proteins to clot strength. Using multiple linear regressions, all coagulation, TEG and HVG variables were used to model postoperative hypercoagulation. However, three components of the routine coagulation assay, including bleeding time, prothrombin time and platelet count, could be modeled to show prolonged postoperative hypercoagulability (P < 0.01). We conclude that all components of the HVG test reflect postoperative coagulopathies; these results suggest that it may be useful in determining the coagulation status of cancer patients perioperatively.

Conclusions

Postoperative hypercoagulability, occurring for at least 1 week after major cancer abdominal surgery, may be demonstrated by the HVG viscoelastotest. This hypercoagulability is not reflected completely by standard coagulation monitoring and the TEG HVG viscoelastotest provides a fast and easy-to-perform bedside test to quantify in vitro hemocoagulation.