Abstract： Objective To compare the influence of different doses of low molecular weight heparin on blood coagulation system of patients who have received thoracic surgery. Methods Eightytwo patients (with lung cancer, esophageal cancer, thymoma, pleural endotheliomas or other diseases) who were treated in Tongji Hospital of Huazhong University of Science and Technology from January 2009 to March 2010 were divided into three groups, based on the time of hospitalization. In the control group, there were 24 patients including 10 females and 14 males with an average age of 43.5±21.3 years. No low molecular weight heparin was given after operation. There were 32 patients in group I, including 14 females and 18 males, with an average age of 45.2±18.6 years. An amount of 0.2 ml (2 125 U) low molecular weight heparin was subcutaneously injected daily during the first 7 days after operation. In group Ⅱ, there were 26 patients including 11 females and 15 males with an average age of 43.8±20.1 years. An amount of 0.4 ml (4 250 U)low molecular weight heparin was subcutaneously injected daily during the first 7 days after operation. The differences of preoperative and postoperative coagulation factors including prothrombin time (PT), activated partial thromboplastin time (APTT), fibrinogen (Fib), D dimer (D-D), platelet count (PLT) and anti-Ⅹa activity were observed. Results The preoperative average values of PT, APTT, Fib, D-D, PLT of all the three groups were in the normal range and showed no significant difference (P gt;0.05). For all three groups, after operation, PT prolonged, APTT shortened, the amount of Fib, D-D increased, PLT reduced on the 3rd day and then increased on the 7th day and anti-Ⅹa activity increased, all of which showed a significant difference from preoperative values (P lt;0.05). The amount of Fib in group Ⅱ was significantly lower than that in group Ⅰ after operation (the 5th day after operation: 4.7±2.5 g/L vs. 7.0±3.3 g/L, P lt;0.05); the amount of D-D in group Ⅱ was significantly lower than that in the control group (the 5th day after operation: 891.3±891.3 μg/L vs. 1 583.2±984.7 μg/L, P lt;0.05) and group Ⅰ (the 5th day after operation: 891.3±891.3 μg/L vs. 1 452.6±1 052.9 μg/L,P lt;0.05); and the anti-Ⅹa activity of group Ⅱ was significantly higher than that in group Ⅰ (the 5th day after operation: 0.54±0.05 U/ml vs. 0.29±0.04 U/ml, P lt;0.05). Conclusion In a certain weight range, fixeddose (4 250 U) of low molecular weight heparin is able to improve postoperative hypercoagulable state and avoid the occurrence of venous thromboembolism without increasing risk of complications like bleeding.

Citation： ZHANG Ni,FU Xiangning.. The Influence of Different Doses of Low Molecular Weight Heparin on Coagulation Function in Patients after Thoracic Surgery. Chinese Journal of Clinical Thoracic and Cardiovascular Surgery, 2011, 18(1): 30-34. doi: Copy