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Preoperative thromboprophylactic administration of low-molecular-weight-heparin significantly decreased the risk of intraoperative bleeding compared with heparin in patients undergoing video-assisted lobectomy for lung cancer.

Background
Due to the threat from venous thromboembolism (VTE) after major thoracic surgery, especially for cancers, guidelines recommend either heparin sodium (unfractionated heparin) or low-molecular-weight-heparin (LMWH) for those patients at high risk of deep vein thrombosis (DVT). However, risk of bleeding remains a major concern for pre-operative administration of anti-coagulation agents. Therefore, this study aimed to compare the bleeding risk of preoperative administration of LMWH and heparin in patients undergoing video-assisted thoracic surgery (VATS) lobectomy for lung cancer.


Methods
A retrospective, single-center study was designed. A total of 130 patients diagnosed with lung cancer were included from August 2016 to January 2018. These patients were divided into two groups. The preoperative administration of heparin group (PH group) had received heparin 5,000 IU, BID (twice a day) both pre- and post-operatively. And the LMWH group (PL group) had received LMWH 4,000 IU, QD (once a day) both pre- and post-operatively. These anticoagulants would not be ceased until patient was discharged or 24-hour postoperative chest drainage volume exceeded 500 mL. Both preoperative and postoperative coagulation parameters including platelet count (PLT), hemoglobin value (HGB), international normalized ratio (INR), prothrombin time (PT), activated partial thromboplastin time (APTT), fibrinogen (FIB), thrombin time (TT), postoperative drainage parameters and intraoperative bleeding volume were compared.


Results
A total of 62 patients were collected in PH group, while 68 patients comprised PL group. Preoperative coagulation parameters, hematologic data and demographic data were comparable. Preoperative duration of two agents (P=0.414), operation time (P=0.155), postoperative HGB (P=0.943), PLT (P=0.244), INR (P=0.469), PT (P=0.651), TT (P=0.407), FIB (P=0.151), drainage duration (P=0.800), duration of heparin and LMWH (P=0.778) were all comparable between the two groups. Compared with PL group, intraoperative bleeding volume (105.11 and 50.26, P<0.001) and postoperative mean drainage volume (251.52 and 216.90 mL, P=0.025) of PH group were significant more. Postoperative APTT (30.17 vs. 28.20 seconds, P=0.022) was significantly longer in PH group.


Conclusions
Compared with preoperative administration of heparin, preoperative thromboprophylactic administration of LMWH significantly decreased the risk of intraoperative bleeding in VATS lobectomy.