zer, and received support from Bayer Healthcare for an investigator initiated registry on VTE prevention in major orthopedic surgery. In 2007, the annual number of total hip and knee arthroplasties in the US was 250,000 and 500,000, respectively. These numbers are expected to increase to 572,000 and 3.48 million for primary THA and TKA, respectively, between 2005 and 2030. Orthopaedic Nutlin-3 surgeons and internists are fully aware of these expected increases in the number of elective THAs/TKAs. The types of patients undergoing THA/TKA are consistent and the risks of surgery are well characterized. Antibiotic prophylaxis for THA/TKA is estimated to decrease the relative risk of wound infection by 81% compared with no prophylaxis.
Similarly, the appropriate use of anticoagulant drugs has been shown to reduce the risk of venous thromboembolism after THA/TKA, and guidelines recommend their routine use after this type of surgery. Without prophylaxis, the incidence of venographic deep vein thrombosis and of pulmonary embolism after THA are 42 57% and 0.9 28%, respectively. The BMS-387032 index event usually occurs at a mean of 21.5 days after surgery typically after hospital discharge. The risk of venographic DVT and PE after TKA is 41 85% and 1.5 10%, respectively. Clinical symptomatic events usually occur at a mean of 9.7 days after TKA and 21.5 days after THA, with 75% occurring after a median hospital stay of 5 days for THA. The current trend is towards much shorter hospital stays, with a mean of less than 3 days for THA and TKA at Roper Hospital in 2009, meaning that the vast majority of symptomatic events will occur on an outpatient basis and, therefore, prophylaxis is mainly an outpatient issue.
The American College of Chest Physicians guidelines recommend prophylaxis with anticoagulants for a minimum of 10 days and up to 35 days after THA to reduce the risk of VTE. After TKA, the ACCP recommends prophylaxis with anticoagulants for at least 10 days and suggests up to 35 days in some patients . Options include vitamin K antagonists, such as warfarin, low molecular weight heparins, such as enoxaparin, and the synthetic pentasaccharide fondaparinux. Although the antiplatelet acetylsalicylic acid is considered by some clinicians to have a role in the prevention of PE, its use alone for thromboprophylaxis is not recommended by the ACCP.
The American Academy of Orthopaedic Surgeons has published guidelines strictly on the prevention 2 Thrombosis of PE, not DVT prophylaxis, recommending that patients at standard risk of both PE and major bleeding should be considered for one of the prophylactic agents evaluated in their guideline, including ASA, LMWHs, synthetic pentasaccharides and warfarin. Those at increased risk of PE and standard risk of major bleeding should be considered for one of the prophylactic agents evaluated in their guideline, including LMWHs, synthetic pentasaccharides, and warfarin. Patients at standard risk of PE and at increased risk of major bleeding should be considered for prophylaxis with ASA or warfarin, as evaluated in their guideline. However, they fail to provide any definitions or guidelines regarding what patients are at increased risk of bleeding and increased risk of PE, or the standard risk of bleeding and PE. Although the AAOS does not specifically give guidance on the prevention of DVT after THA/TKA, DVT prophylaxis is as important as the prevention of PE because after an initial DVT, patients have a 10% risk of recurrent VTE