Aspirin Thromboprophylaxis Is Associated With Less Major Bleeding Events Following Total Joint Arthroplasty

Aspirin as Venous Thromboembolism Prophylaxis in Arthroplasty Patients: An Analysis of Clinical Practice Guidelines Recommendations

BACKGROUND

Venous thromboembolism (VTE) is a recognized postoperative complication of hip or knee arthroplasty and incurs major morbidity and mortality. While anticoagulants are the mainstay of chemoprophylaxis, aspirin has recently emerged as a popular prophylactic agent. However, there is a lack of high-quality evidence comparing aspirin to anticoagulants as a method of VTE prophylaxis, and current guidelines are conflicting regarding using aspirin as first-line chemoprophylaxis. We aimed to investigate guideline characteristics that are associated with the recommendation for or against aspirin as a first-line agent.

METHODS

MEDLINE, Embase, Cumulative Index to Nursing and Allied Health Literature, and PubMed databases were searched from 1966 to January 2024 to identify clinical practice guidelines for VTE prophylaxis in adult hip or knee arthroplasty inpatients of average risk. The characteristics of the guideline were collected by 2 independent reviewers. Logistic regression was used to test the association between the recommendation for or against aspirin and guideline characteristics.

RESULTS

There were 26 guidelines published from February 2003 to September 2023 and included in this study. There were 5 guidelines that recommended aspirin and 11 guidelines that recommended against aspirin as first-line therapy. With a more recent year of publication, aspirin was more likely to be recommended (odds ratio 1.72, 95% confidence interval: 1.05 to 2.84) and less likely to be recommended against (odds ratio 0.61, 95% confidence interval: 0.41 to 0.90). No other variables, including the level of evidence used, the composition of the guideline working group, or the objective of the guideline, were associated with the recommendation for or against aspirin.

CONCLUSIONS

Guidelines were inconsistent in their recommendations regarding aspirin as first-line therapy as VTE prophylaxis in arthroplasty patients. Adequately powered randomized controlled trials using modern practices, such as early postoperative mobilization, are needed to better inform clinical practice guidelines.

Trends in Deep Vein Thrombosis Prophylaxis After Total Knee Arthroplasty: 2016 to 2021

BACKGROUND

In 2011, the American Academy of Orthopaedic Surgeons released a consensus recommending venous thromboembolism (VTE) prophylaxis after total knee arthroplasty (TKA). The purpose of our study was to examine (1) incidences of postoperative complications, including pulmonary embolism (PE), deep vein thrombosis (DVT), and transfusion rates; (2) trends from 2016 to 2021 in VTE prophylaxis; and (3) independent risk factors for 90-day total complications following TKA between aspirin, enoxaparin, rivaroxaban, and warfarin.

METHODS

Using a national, all-payer database from 2016 to 2021, we identified all patients who underwent primary TKA. Exclusions included all patients who had prescribed anticoagulants within 1 year prior to TKA, hypercoagulable states, and cancer. Data were collected on baseline demographics, including age, sex, diabetes, and a comorbidity index, in each of the VTE prophylaxis cohorts. Postoperative outcomes included rates of PE, DVT, and transfusion. Multivariable regressions were performed to determine independent risk factors for total complications at 90 days following TKA.

RESULTS

From 2016 to 2021, aspirin was the most used anticoagulant (n = 62,054), followed by rivaroxaban (n = 26,426), enoxaparin (n = 20,980), and warfarin (n = 13,305). The cohort using warfarin had the highest incidences of PE (1.8%) and DVT (5.7%), while the cohort using aspirin had the lowest incidences of PE (0.6%) and DVT (1.6%). The rates of aspirin use increased the most from 2016 to 2021 (32.1% to 70.8%), while the rates of warfarin decreased the most (19.3% to 3.0%). Enoxaparin, rivaroxaban, and warfarin were independent risk factors for total complications at 90 days.

CONCLUSIONS

An epidemiological analysis of VTE prophylaxis use from 2016 to 2021 shows an increase in aspirin following TKA compared to other anticoagulant cohorts in a nationally representative population. This approach provides more insight and a better understanding of anticoagulation trends over this time period in a nationally representative sample.

Low-Dose Aspirin Is the Safest Prophylaxis for Prevention of Venous Thromboembolism After Total Knee Arthroplasty Across All Patient Risk Profiles

BACKGROUND

The International Consensus Meeting on Venous Thromboembolism (ICM-VTE) in 2022 proclaimed low-dose aspirin as the most effective agent in patients across all risk profiles undergoing joint arthroplasty. However, data on large patient populations assessing trends in chemoprophylactic choices and related outcomes following total knee arthroplasty (TKA) remain scant. The present study was designed to characterize the clinical use of various chemoprophylactic agents in patients undergoing TKA and to determine the efficacy of aspirin compared with other agents in patient groups stratified by VTE risk profiles.

METHODS

This study utilized a national database to determine the proportion of patients undergoing TKA who received low-dose aspirin versus other chemoprophylaxis between 2012 and 2022. VTE risk profiles were determined on the basis of comorbidities established in the ICM-VTE. The odds ratios (ORs) and 95% confidence intervals (CIs) between various classes of thromboprophylaxis in patients with high and low risk of VTE were calculated. The odds of deep-vein thrombosis (DVT), pulmonary embolus (PE), bleeding events, infections, mortality, and hospitalizations were also assessed in the 90-day postoperative period for propensity-matched cohorts receiving low-dose (81 mg) aspirin only versus other prophylaxis, segregating patients by VTE risk profile.

RESULTS

A total of 126,692 patients undergoing TKA across 60 health-care organizations were included. The proportion of patients receiving low-dose aspirin increased from 7.65% to 55.29% between 2012 and 2022, whereas the proportion of patients receiving other chemoprophylaxis decreased from 96.25% to 42.98%. Low-dose-aspirin-only use increased to approximately 50% in both high-risk and low-risk populations but was more likely in low-risk populations (OR, 1.17; 95% CI, 1.15 to 1.20) relative to high-risk populations. Both low-risk and high-risk patients in the low-dose-aspirin-only cohorts had decreased odds of DVT, PE, bleeding, infections, and hospitalizations compared with other prophylaxis regimens.

CONCLUSIONS

The findings of the present study on a very large population of patients undergoing TKA support the recent ICM-VTE statement by showing that low-dose aspirin is a safe and effective method of prophylaxis in patients across various risk profiles.

LEVEL OF EVIDENCE

Therapeutic Level III . See Instructions for Authors for a complete description of levels of evidence.

Trends in deep vein thrombosis prophylaxis after total hip arthroplasty: 2016 to 2021

Introduction

Venous thromboembolism (VTE) has long been acknowledged as a potential complication of total hip arthroplasty (THA) contributing to heightened patient morbidity, mortality, and substantial healthcare costs. We aimed to: 1) assess trends in VTE prophylaxis utilization between 2016 and 2021; 2) determine the incidence of postoperative VTE and transfusions; and 3) identify independent risk factors for 90-day VTE and transfusion risks following THA in relation to the use of aspirin, dabigatran, enoxaparin, rivaroxaban, and warfarin.

Methods

A national, all-payer database was queried from January 1, 2016 and December 31, 2022. Use trends for aspirin, enoxaparin, rivaroxaban, dabigatran, and warfarin as thromboprophylaxis following THA was assessed. Incidence of ninety-day postoperative outcomes assessed included rates of 90-day postoperative VTE and transfusion.

Results

From 2016 to 2021, aspirin (n = 36,346) was the most used agent for VTE prophylaxis after THA, followed by dabigatran (n = 13,065), rivaroxaban (n = 11,790), enoxaparin (n = 11,380), and warfarin (n = 6326). Independent risk factors for 90-day VTE included CKD, COPD, CHF, obesity, dabigatran, enoxaparin, rivaroxaban, and warfarin (all p < 0.05).

Conclusion

Aspirin was used with increasing frequency and demonstrated lower rates of VTE and transfusion following THA, compared to dabigatran, enoxaparin, rivaroxaban, and warfarin. These findings seem to indicate that the increasing use of aspirin in VTE prophylaxis has been accomplished in appropriately selected patients.

Prevention of surgical site infection: a ten-step approach

Surgical site infection (SSI) is a common cause of morbidity and mortality in patients undergoing surgery. Similarly, periprosthetic joint infection (PJI), is a major cause of failure after total joint arthroplasty (TJA). As the annual volume of TJA procedures is projected to rise, so will the rate of subsequent SSI and PJI. Currently, prevention has been identified as the single most important strategy for combating SSI/PJI. Hence, the present article will serve as a summary of an evidence-based ten-step approach for SSI/PJI prevention that may help orthopedic surgeons with their infection prevention strategies.

Aspirin for Venous Thromboembolic Prophylaxis Following Total Hip and Total Knee Arthroplasty: An Analysis of Safety and Efficacy Accounting for Surgeon Selection Bias

BACKGROUND

Aspirin may be effective at preventing venous thromboembolism following total knee arthroplasty (TKA) or total hip arthroplasty (THA). Current evidence is limited by bias as many surgeons who use aspirin prescribe for high-risk patients alternative chemoprophylactic agents. Therefore, this study aimed to evaluate the risk of pulmonary embolism (PE) and deep vein thrombosis (DVT) in patients who received aspirin and warfarin while accounting for surgeon selection bias.

METHODS

A national database was queried for patients undergoing primary elective TKA or THA from 2015 to 2020. Patients whose surgeon used aspirin in >90% of their patients were compared to patients whose surgeon used warfarin in >90% of cases. Instrumental variable analyses were performed to assess for PE, DVT, and transfusion while accounting for selection bias. Among TKA patients, 26,657 (18.8%) were in the warfarin cohort and 115,005 (81.2%) were in the aspirin cohort. Among THA patients, 13,035 (17.7%) were in the warfarin cohort and 60,726 (82.3%) were in the aspirin cohort.

RESULTS

Analyses were unable to identify a difference in the risk of PE (TKA: adjusted odds ratio [aOR]: 0.98, P = .659; THA: aOR = 0.93, P = .310) and DVT (TKA: aOR = 1.05, P = .188; THA: aOR = 0.96, P = .493) between the aspirin and warfarin cohorts. However, the aspirin cohort was associated with a lower risk of transfusion (TKA: aOR = 0.58, P < .001, THA: 0.84, P < .001).

DISCUSSION

After accounting for surgeon selection bias, aspirin was as effective as warfarin at preventing PE and DVT following TKA and THA. Furthermore, aspirin was associated with a lower risk of transfusion compared to warfarin.

Comparison of 90-Day Adverse Events Associated With Aspirin and Potent Anticoagulation Use for Venous Thromboembolism Prophylaxis: A Cohort Study of 72,288 Total Knee and 35,142 Total Hip Arthroplasty Patients

BACKGROUND

While aspirin is acceptable for venous thromboembolism (VTE) prophylaxis following total joint arthroplasty in most patients, more potent agents are used in patients considered higher risk for VTE. We evaluated the efficacy and safety of aspirin versus potent anticoagulation agents following total knee arthroplasty (TKA) and total hip arthroplasty (THA).

METHODS

A cohort study of 72,288 TKA and 35,142 THA from the Kaiser Permanente Total Joint Replacement Registry was performed (2009 to 2019). Identified medications were aspirin, factor Xa inhibitors, low-molecular-weight heparin (LMWH), and warfarin. A validated VTE risk score was assigned to each patient. Propensity score-weighted logistic regressions were used to evaluate 90-day VTEs. Noninferiority testing was performed with a margin of 1.25 using the upper bound (UB) of the 1-sided 95% CI.

RESULTS

For TKA, aspirin was not inferior to LMWH (odds ratio [OR] = 0.77, UB = 1.09) and warfarin (OR = 0.64, UB = 0.90); there was no evidence to support noninferiority of aspirin compared to factor Xa inhibitors. Findings were consistent for THA (LMWH: OR = 0.59, UB = 0.75; warfarin: OR = 0.69, UB = 0.89). TKA was considered higher risk for VTE, whereas aspirin use demonstrated noninferiority compared to warfarin (OR = 0.54, UB = 0.81), we lacked evidence of noninferiority when compared to LMWH and factor Xa inhibitors. We lacked evidence of noninferiority of aspirin versus any potent anticoagulation in higher-risk THA.

CONCLUSION

Aspirin was found to be effective and safe for VTE prevention in primary total joint arthroplasty, including in patients considered higher risk for VTE.

LEVEL OF EVIDENCE

III.