**5. Current trend**

*4.1.3. Multimodal methods*

50 Primary Total Knee Arthroplasty

*4.1.4. Concerns with thromboprophylaxis*

effective post THA, but not TKA [28].

of surgery.

most surgeons.

Combining mechanical and pharmacological prophylaxis enables greater reduction of the risk of DTV. It also reduces the dosage of anticoagulants and thus the risk of bleeding, and achieves the same or even better thromboprophylaxis than monotherapy. Classifying patients into low or high risk of developing VTE is advocated. Low-risk patients received aspirin and intermittent calf compression, whereas high-risk patients received LMWH or warfarin and intermittent calf compression. All patients have to be mobilized within 24 h

Few studies have advocated less potent pharmacological agents for low-risk patients and more potent agents for high-risk patients as the results showed negligible incidence of DVT, PE, and wound hematoma in both the groups [21]. Few recent studies show superior effects for aspirin in multimodal thromboprophylaxis when compared to warfarin [13, 14, 22].

The risks associated with thromboprophylaxis are mainly hemorrhage, wound hematoma, persisting wound drainage, failure of wound healing, risk of infection, and blood loss requiring transfusion. One of the main drawbacks of initiating thromboprophylaxis is the high incidence of major bleeding, reaching up to 4–7.9% [23]. More potent the prophylactic agent, more the incidence. Oral agents hence have lower bleeding rates [15]. A study on 290 patients post-TJA using 10-day course of inj. enoxaparin 30 mg twice daily showed high incidence of 3–5% of readmission, re-exploration, and prolonged hospitalization for wound drainage and bleeding [24]. There were increased rates of return to the operating room for wound complications, wound drainage for more than 7 days, and incidence of symptomatic DVT in 3.8% patients and nonfatal PE in 1.3% patients. Parvizi et al. reviewed 78 septic failure cases that underwent revision and showed a direct correlation between excessive anticoagulation and development of periprosthetic infection [25]. The occurrence of such complications after elective TJA due to the use of prophylactic agents is heartbreaking to

Also, timing of initiation of the prophylaxis is also debated. Two schools of thought are initiation of LMWH 12 h preoperative and 12 h postoperative. Earlier initiation of prophylaxis has shown greater efficacy in preventing DVT but also causes a higher incidence of bleeding. The decision about which agent and when to initiate chemoprophylaxis should be based on the

There is still no consensus on the duration of the use of prophylaxis too. The recently released new AAOS guidelines do not provide a specific duration for prophylaxis [27]. Earlier ACCP guidelines advocated a minimum of 10 days of prophylaxis, with extended prophylaxis up to 35 days. AAOS advised different duration for different agents: LMWH/fondaparinux for 7–12 days and aspirin/warfarin for 6 weeks. Extended prophylaxis with only LMWH was

balanced efficacy-bleeding ratio of the prophylactic agents [26].

Ideal DVT prophylaxis method still remains an enigma. The choice is based on patient characteristics and surgeon's experience. Aspirin is recognized as a primary chemoprophylactic agent with the adaptation of the recent ACCP guidelines by the Surgical Care Improvement Project (SCIP). They strongly endorse risk stratification for VTE prophylaxis and opined that aspirin will become the mainstay of prevention of VTE for the majority of patients after TJA. Thus, we could optimize outcomes for our patients, by preventing the feared VTE while limiting bleeding complications that can occur with other aggressive anticoagulants [29]. Identifying and stratifying the patients at risk for DVT remains a challenge. As a general consensus, it is taken that patients post TJA can receive aspirin as thromboprophylaxis without much risk. But, those patients at very high risk may need more potent agents and careful monitoring [30].

Further research is needed to identify patients at major risk and probability of VTE and bleeding. The current clinical guidelines provide an orthopedic surgeon with more latitude, and choices of VTE prophylaxis without emphasis on aggressive chemical, and often unneeded prophylaxis. The key to determining the appropriate chemical prophylaxis for patients is to balance safety and efficacy while minimizing bleeding. Modern arthroplasty surgeons advocate early postoperative mobilization and use of mechanical prophylaxis in combination with chemoprophylaxis according to the risk stratification, which of course seems to be a reasonable safer approach.
