Aspirin for lower limb arthroplasty thromboprophylaxis: review of international guidelines

Upper Extremity Deep Venous Thrombosis Prophylaxis After Elective Upper Extremity Surgery

Historically, upper extremity deep venous thromboses (DVTs) have been rare; however, their incidence has increased as awareness has increased. Patients who develop upper extremity DVTs often have multiple comorbidities. However, in the past decade, studies have found a small risk of upper extremity DVTs associated with orthopedic procedures involving the upper extremity. The risk of complications following a DVT, including postthrombotic syndrome and pulmonary embolism, is substantially higher with a DVT of the upper extremity compared with a DVT of the lower extremity. Furthermore, there is no consensus regarding the role and efficacy of prophylactic measures in preventing upper extremity DVT after upper extremity surgery. This article discusses the use of prophylactic agents after elective upper extremity surgery, with an emphasis on the efficacy of commonly used interventions. [Orthopedics. 2018; 41(1):21-27.].

Aspirin and the prevention of venous thromboembolism following total joint arthroplasty: commonly asked questions

The number of arthroplasties being performed increases each year. Patients undergoing an arthroplasty are at risk of venous thromboembolism (VTE) and appropriate prophylaxis has been recommended. However, the optimal protocol and the best agent to minimise VTE under these circumstances are not known. Although many agents may be used, there is a difference in their efficacy and the risk of bleeding. Thus, the selection of a particular agent relies on the balance between the desire to minimise VTE and the attempt to reduce the risk of bleeding, with its undesirable, and occasionally fatal, consequences.

Acetylsalicylic acid (aspirin) is an agent for VTE prophylaxis following arthroplasty. Many studies have shown its efficacy in minimising VTE under these circumstances. It is inexpensive and well-tolerated, and its use does not require routine blood tests. It is also a ‘milder’ agent and unlikely to result in haematoma formation, which may increase both the risk of infection and the need for further surgery. Aspirin is also unlikely to result in persistent wound drainage, which has been shown to be associated with the use of agents such as low-molecular-weight heparin (LMWH) and other more aggressive agents.

The main objective of this review was to summarise the current evidence relating to the efficacy of aspirin as a VTE prophylaxis following arthroplasty, and to address some of the common questions about its use.

There is convincing evidence that, taking all factors into account, aspirin is an effective, inexpensive, and safe form of VTE following arthroplasty in patients without a major risk factor for VTE, such as previous VTE.

Cite this article: Bone Joint J 2017;99-B:1420–30.

Rate of Transfusions After Total Knee Arthroplasty in Patients Receiving Lovenox or High-Dose Aspirin

BACKGROUND

Controversy continues regarding the use of powerful anticoagulants for venous thromboembolism prophylaxis in patients undergoing total knee arthroplasty (TKA). To comply with institution-mandated guidelines and pressure from hospitalist intent on complying with conventionally recommended anticoagulation guidelines, we singularly changed our chemoprophylaxis practice from using aspirin to Lovenox and noted that transfusion rates increased substantially.

METHODS

A retrospective case review was performed to evaluate transfusion requirement differences in primary TKA patients receiving Lovenox (unilateral TKA: n = 135, bilateral TKA: n = 44) or aspirin (unilateral TKA: n = 153, bilateral TKA: n = 45) for venous thromboembolism prophylaxis. Pearson's chi-square tests were used to evaluate surgical complications and the rate of transfusions between aspirin and Lovenox groups. Independent t tests were used to evaluate the units of packed red blood cells transfused, hemoglobin drop, and hematocrit drop between aspirin and Lovenox groups.

RESULTS

Lovenox was found to significantly increase (P < .01) the rate of transfusion, units of packed red blood cells, hemoglobin drop, and hematocrit drop compared to aspirin in both unilateral and bilateral TKA patients, without significantly decreasing venous thromboembolism events (aspirin: 3 pulmonary embolisms and 4 deep venous thrombosis; Lovenox: 3 pulmonary embolisms and 2 deep venous thrombosis).

CONCLUSION

Our findings suggest that aspirin is as effective as Lovenox in preventing venous thromboembolism and that the use of Lovenox significantly increases the likelihood of requiring transfusions after surgery.

DVT prophylaxis after TKA: routine anticoagulation vs risk screening approach - a randomized study

The American College of Chest Physicians (ACCP) recommended routine anticoagulation for thromboprophylaxis in patients undergoing lower limb arthroplasty. We compared results of routine anticoagulation Vs risk stratified approach for Deep Venous Thrombosis (DVT) prophylaxis after TKA in terms of symptomatic DVT and wound complications. Nine hundred TKAs done in 673 patients were randomized after DVT risk screening to routine anticoagulation (n = 450) or to risk stratification (n = 450) and selective anticoagulation. 194 patients in the risk screening group received only Aspirin. Primary outcome was symptomatic DVT and wound complication. This randomized study showed that the symptomatic DVT rates after TKA were similar whether patients were routinely anticoagulated or selectively anticoagulated after risk screening. However there was a significantly higher incidence of wound complications (P < 0.014) after routine anticoagulation.