[Advancement of prophylaxis and therapy for venous thromboembolism]

Recently in Japan, venous thromboembolism (VTE) [deep vein thrombosis (DVT)/pulmonary thromboembolism (PTE)] has increased with the Westernization of eating habits and aging of society. In the West, the prophylaxis guidelines have been discussed for many years. Unfortunately, Japan falls far behind the West in this area. Therefore, the necessity of thromboprophylaxis in Japanese people should be emphasized based on reliable VTE studies in Japan. In orthopedic surgery, prospective multicenter studies in Japan indicate that the incidence of DVT/PTE in total hip or knee replacement surgery and hip fracture surgery were almost equal to those in Western people. Furthermore, a multi-center, prospective epidemiological study in Japan revealed that the incidence of VTE following major abdominal surgery was 24.3%. We developed Japanese Guidelines for VTE prophylaxis based on the 6th ACCP guideline in 2004. The incidence of perioperative PTE in Japan has been investigated by the Japanese Society of Anesthesiologists since 2002. The rate of perioperative PTE was estimated to be 4.41 per 10,000 operations in 2002, and 4.76 in 2003; however, it decreased to 3.61 immediately after the guideline for thromboprophylaxis was issued and the management fee for PTE prophylaxis became covered by health insurance in April 2004. Furthermore, it markedly decreased in 2005. However, mechanical prophylaxis is not sufficient to prevent PTE, and advanced prophylaxis by anticoagulants, such as low-molecular-weight heparin/selective Xa inhibitor along with unfractionated heparin (UFH)/vitamin K antagonists (VKA) will be essential. The advanced revised guidelines for VTE prophylaxis based on our clinical evidence will be established in the near future. As for treatment for VTE, anticoagulant and thrombolytic therapies are essential. In cases with VTE, UFH followed by VKA (INR: 1.5-2.5) is standard. In cases of PTE with shock, thrombolytic therapy such as tissue plasminogen activator or urokinase, catheter intervention, or surgical procedures under pericutaneous cardiopulmonary support should be selected based on the severity of PTE.