Thromboelastography Values Remain Hypercoagulative 6 Months After Obesity Surgery: a Pilot Study.

PURPOSE: Obesity causes a prothrombotic state and is known as a predisposing factor for thromboembolic events. In this pilot study, we assessed the impact of surgery for obesity and the subsequent weight loss on blood coagulation using traditional coagulation tests and thromboelastography (TEG).

MATERIAL AND METHODS: We studied blood samples from 18 patients receiving bariatric surgery. Besides traditional blood coagulation tests and high-sensitivity C-reactive protein (hsCRP) as a marker of inflammation, the TEG parameters reaction time (R), kinetics time (K), angle (α), maximum amplitude (MA), clot strength (G), and lysis percent at 60 min (LY60) were determined preoperatively and on the first postoperative day and 6 months after surgery.

RESULTS: Altogether, 54 samples were analyzed. The median MA (71.3 mm), G (12,403.3 d/sc), and hsCRP (3.5 mg/l) were elevated preoperatively. The median hsCRP further increased on the first day postoperatively, but declined to the normal range 6 months after surgery, while MA and G remained elevated. In traditional coagulation tests, there was an increase in median fibrinogen and D-dimer postoperatively. D-dimer normalized (0.4 mg/l) during the study period, while the fibrinogen level (4.1 g/l) remained above the upper limit of normal.

CONCLUSIONS: Measured by TEG, patients receiving bariatric surgery have hemostatic abnormalities indicating hypercoagulation at the 6-month follow-up visit, suggesting an elevated risk for thromboembolic events for at least 6 months after surgery.