**9. Appendix**

188 Venous Thrombosis – Principles and Practice

The expanding use of laparoscopy last 3 decades has profoundly changed surgical diagnosis and therapy. However there is still some controversy over the best practice for prevention of deep vein thrombosis (DVT) during laparoscopic surgery. There is considerable uncertainty related to the thromboembolic risk after laparoscopic procedures, and the use of thromboprophylaxis is controversial. Surgical trauma is generally less with laparoscopic than with open abdominal surgery, but activation of the coagulation system is similar to or only slightly less with laparoscopic procedures. Laparoscopic operations may be associated with longer surgical times than comparable open procedures. Both pneumoperitoneum and the reverse Trendelenburg position reduce venous return from the legs, creating venous stasis. Patients undergoing laparoscopic procedures may have shorter hospital stays, but they may not mobilize more rapidly at home than those who have had open procedures. Despite the paucity of evidence, the European Association for Endoscopic Surgery has recom mended that intraoperative IPC be used for all prolonged laparoscopic procedures (66). In 2006, the Society of American Gastrointestinal Endoscopic Surgeons recommended the use of similar thromboprophylaxis options for laparoscopic procedures as for the equivalent open surgical procedures (67). However, available evidence does not support a recommendation for the routine use of thromboprophylaxis in these patients (68,69,70). Furthermore, with anticoagulant thromboprophylaxis, the risk of major bleeding may exceed the rate of thrombotic complications(71). Patients who are at particularly high thromboembolic risk can be considered for thromboprophylaxis with any of the modalities

Treatment for VTE has been widely studied, and treatment guidelines have been published and frequently updated by the American College of Chest Physicians (ACCP), American College of Emergency Physicians, Eastern Association for the Surgery of Trauma, and Institute for Clinical Systems Improvement(1,3). Generally, acute treatment consists of lowmolecular-weight heparin (LMWH) or unfractionated heparin (UFH) for 4 to 5 days, with overlapping therapy to warfarin until an international normalized ratio (INR) of >2 for two consecutive days is achieved. Anticoagulation should be continued for at least 3 to 12 months, depending on the site of thrombosis and risk factors. Failure to provide adequate VTE treatment can result in patient morbidity and mortality, with a substantial economic burden(73). Although the evidence and consensus strongly favor LMWH treatment for up to 6 months in patients with cancer with established VTE, evidence is lacking to support continuing treatment beyond 6 months. It is likely that anticoagulation can be safely discontinued in certain patients (eg, patients who developed a VTE while on adjuvant chemotherapy and are in complete remission withnoplans for further treatment). Conversely, certain patients will continue to be at risk for recurrent VTE (eg, a patient with cancer with metastatic disease with plans for indefinite chemotherapy). Data from welldesigned randomized clinical trials are essential for clinicians to make evidencebased

Activation of the hemostatic system promotes tumor growth, angiogenesis, and metastasis. Antithrombotic agents could therefore potentially influence tumor biology and outcomes in patients with cancer. Multiple recent studies have evaluated the effect of anticoagulants on

**7. Laparoscopic surgery** 

currently recommended for surgical patients (3,72).

recommendations in these varied settings.

**8. Treatment of VTE** 

An informative summary from American College of Chest Physicians Evidence-Based Clinical Practice Prevention of Venous Thromboembolism Guidelines (8th Edition)(3).
