Clinical Effectiveness and Safety of Aspirin for Venous Thromboembolism Prophylaxis After Total Hip and Knee Replacement: A Systematic Review and Meta-analysis of Randomized Clinical Trials

Aspirin in prevention of venous thromboembolism following hip fracture surgery: A systematic review and meta-analysis

Background

Many orthopaedic surgeons routinely prescribe aspirin (ASA) as prophylaxis for venous thromboembolism (VTE) following hip fracture surgery (HFS). The purpose of this study is to assess the effectiveness of aspirin to other agents in preventing VTE and mortality following hip fracture surgery.

Methods

Following PRISMA guidelines, we performed a search for HFS studies from 1998 to 2023 reporting comparisons between aspirin and other chemoprophylaxis methods for VTE (DVT - deep vein thrombosis; PE - pulmonary embolism). SPSS Meta-analysis function was used to calculate Mean Effect Size Estimate (MESE) and 95 % Confidence Intervals for each outcome. Reverse Fragility Index (RFI) and Fragility Quotient (FQ) were calculated for each study.

Results

Of the 847 articles screened, 4 studies with 5 comparisons met the search criteria to be included for analysis. A total of 1194 participants were included in these studies. There was a decreased risk of mortality seen with use of aspirin compared to other agents (MESE = 0.86, 95 % CI: [0.07-1.66]; p=.03). There was no increased risk of DVT or PE with use of aspirin (both p>.4). The overall RFI and FQ for all 19 outcomes were 12 (IQR: 6.5-15) and 0.080 (IQR: 0.027-0.110), respectively. Ten studies (52.6 %) reported a loss-to-follow-up (LTF) greater than the overall RFI.

Conclusions

Aspirin demonstrates similar protective effects on prevention of VTE compared to other agents and may have significant protective effects on overall mortality following surgical intervention for hip fractures. However, the current evidence concerning its use in this arena is less than robust, with more than half of the studied outcomes considered statistically fragile.

Examining postpartum anticoagulation practices: An international survey of healthcare providers

BACKGROUND

The risk of venous thromboembolism (VTE) is 15 to 35-fold higher in the postpartum period compared to non-pregnant individuals. Clinical practice guidelines recommend the use of postpartum thromboprophylaxis with low molecular weight heparin (LMWH) for 6 weeks in individuals at high risk of developing VTE. However, a marked reduction in the risk of VTE risk occurs beyond the third week of the postpartum period.

OBJECTIVE

We sought to characterize practice patterns of clinicians who manage postpartum individuals at high risk of VTE.

METHODS

We conducted a cross-sectional study using a self-administered electronic questionnaire. The survey explored the use of postpartum thromboprophylaxis in high-risk individuals. Descriptive statistics were used to summarize survey responses.

RESULTS

Of the 113 participants that responded to the initial invitation, 78 completed the survey (Europe (53.9 %); North America (23.2 %); Australia and New Zealand (19.0 %)). For individuals with a prior unprovoked or provoked deep venous thrombosis or pulmonary embolism, cerebral vein thrombosis and splanchnic vein thrombosis, 97.4 %, 93.5 %, 91.0 % and 88.5 % of the respondents recommended six weeks of postpartum thromboprophylaxis using LMWH, respectively. The recommendation for 6 weeks of thromboprophylaxis in patients with sickle cell disease and obstetric APS was comparatively lower (70.5 and 78.2 % respectively). Respondents with higher practice volumes and more years of experience in clinical practice were more likely to recommend a shorter duration of thromboprophylaxis.

CONCLUSION

Our study highlights the variability in clinician recommendations and the acceptability of treatment durations for postpartum thromboprophylaxis in high-risk conditions. Prospective studies are needed to determine optimal duration and establish evidence-based management.

Lipid Disorders and Pregnancy

Practicing endocrinologists are likely to confront 2 major issues that occur with dyslipidemias during pregnancy. The most dramatic is the development of severe hypertriglyceridemia leading to acute pancreatitis. The second is the approach to treatment of familial hypercholesterolemia, a common genetic disorder. This article reviews the normal physiology and the pathophysiology of lipoproteins that occurs with pregnancy and then discusses the approaches to prevention and/or treatment of dyslipidemia in pregnancy with a focus on lifestyle and acceptable drug therapies.

Trends in Venous Thromboembolism and Chemoprophylaxis Utilization in Elective Total Knee Arthroplasty From 2011 to 2020

BACKGROUND

Venous thromboembolism (VTE) is a feared complication of joint arthroplasty, leading to recent clinical practice guidelines aimed at VTE prevention and prophylaxis. However, limited studies have examined national changes in practice regarding chemoprophylaxis and the resultant changes in VTE rates. The purpose of this study was to identify: (1) the temporal trends in thrombotic complications; and (2) changes in chemoprophylaxis utilization in patients undergoing elective total knee arthroplasty (TKA).

METHODS

A retrospective study was conducted using a large all-payer claims dataset. Patients who underwent osteoarthritis-indicated TKA between 2011 and 2020 were identified. Annual rates of VTE, including deep vein thrombosis and pulmonary embolism, within 90 days of TKA were determined. Utilization patterns for postoperative aspirin and anticoagulant medications were observed. Temporal trends were analyzed with linear regression and the calculation of the cumulative annual growth rate. Multivariable logistic regression was conducted to account for the effects of age and comorbidities.

RESULTS

A total of 1,263,351 TKA patients were identified between 2011 and 2020. There were significant reductions in VTE rates (2.9% in 2011 to 1.8% in 2020), deep vein thrombosis rates (2.0% in 2011 to 1.3% in 2020), and pulmonary embolism rates (1.1% in 2011 to 0.6% in 2020). Postoperative utilization of aspirin increased from 5.9% in 2011 to 53.2% in 2020, whereas utilization of anticoagulants decreased from 94.1% in 2011 to 46.8% in 2020. Among anticoagulants, direct factor Xa inhibitors had the greatest increase in utilization (4.6 to 69.7%). The average reimbursement associated with VTE after TKA decreased from $18,061 in 2011 to $7,835 in 2020.

CONCLUSIONS

The incidence rate and economic burden of VTE after TKA have significantly declined since 2011. There has been a trend toward increased aspirin and direct oral anticoagulant utilization for postoperative chemoprophylaxis.

LEVEL OF EVIDENCE

Level III.

Outcomes Following Total Hip Arthroplasty in Patients Who Have Von Willebrand Disease Depend on Postoperative Anticoagulation

BACKGROUND

Von Willebrand disease (VWD) is the most common congenital bleeding disorder. This autosomal dominant condition arises from quantitative or qualitative defects of Von Willebrand factor. To our knowledge, this study leveraged a national database to characterize the largest VWD cohort of total hip arthroplasty (THA) patients to date, assessing 90-day postoperative adverse events and 5-year revision-free survival.

METHODS

Adult patients who underwent primary THA for osteoarthritis were identified from January 2010 to October 2021 in a nationwide database. Patients who had and did not have VWD were matched (4:1) on age, sex, and Elixhauser Comorbidity Index and compared with multivariable logistic regression. Patients were then categorized based upon venous thromboembolism (VTE) chemoprophylaxis prescription patterns to compare bleeding and thrombotic adverse events.

RESULTS

Of 544,851 THA patients, VWD was identified in 309 patients (0.06%). The matched cohorts contained 1,221 patients who did not have VWD and 306 patients who have VWD. On multivariable analysis, VWD patients had increased odds of 90-day VTE (odds ratio [OR] = 1.86) and hematoma (OR = 3.40) (P < .05 for all). No difference in 5-year revision-free survival was found. The VWD patients receiving aspirin or no prescriptions had greater odds of VTE (OR = 2.39, P = .048). Those on other chemoprophylaxis agents had greater odds of hematoma (OR = 4.84, P = .006).

CONCLUSIONS

Patients with VWD undergoing THA had increased odds of 90-day VTE if using aspirin or no prescriptions, or hematoma if using other chemoprophylaxis. There is a delicate balancing act of clotting versus bleeding that must be considered in managing such patients, but it was reassuring that no difference in overall 5-year revision-free survival was found.

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.

Efficacy and safety of aspirin in venous thromboembolism prevention after total hip arthroplasty, total knee arthroplasty or fracture

Background: This study aims to analyse the efficacy and safety of aspirin in the prevention of venous thromboembolism (VTE) for patients undergoing total hip arthroplasty (THA), total knee arthroplasty (TKA) or fracture. Patients and methods: Two independent investigators searched PubMed, Embase, Cochrane and ClinicalTrials.gov from January 2000 to June 2023 to retrieve randomized control trials (RCTs) about aspirin in VTE prevention after arthroplasty or fracture. Then, the relative risk (RR) was utilized to evaluate its efficiency and safety. Results: A total of 16 RCTs with 27,864 patients were included. There was no statistical difference in the incidence of deep-vein thrombosis (RR: 1.31, p = 0.100), pulmonary embolism (RR:1.05, p = 0.850), VTE (RR:1.28, p = 0.290), major bleeding (RR:0.96, p = 0.900), and death (RR:1.01, p = 0.960) between the aspirin group and the anticoagulants group. Subgroup analysis showed that a relatively higher incidence of deep-vein thrombosis in patients undergoing TKA (RR:1.49, p = 0.030), fracture (RR:1.48, p = 0.001), patients receiving 81 mg aspirin twice daily (RR:1.48, p = 0.001) and patients from North America (RR:1.57, p<0.001) when comparing aspirin with anticoagulants. Meanwhile, the incidence of VTE was higher in patients receiving 100 mg aspirin once daily (RR:1.82, p<0.001) compared with anticoagulants. Additionally, the incidence of all bleeding (RR:2.00, p = 0.030) was higher in patients receiving aspirin in Asia compared with anticoagulants. Conclusions: In terms of clinical effectiveness and safety, aspirin (antiplatelet agent) was generally not inferior to anticoagulants in the prevention of VTE after THA, TKA, or fracture. Notably, the clinical effectiveness of aspirin was affected by different surgical types, the doses of aspirin and races.

Mendelian randomization of stroke risk after total hip and knee replacements

Objective

Previous epidemiological studies have indicated an increased risk of neurovascular diseases in patients following total hip and knee replacements. However, definitive conclusions regarding the increased risk of stroke post-replacement remain elusive. Therefore, we conducted a two-sample Mendelian randomization study to investigate the causal relationship between total hip and knee replacements and stroke.

Methods

We utilized summary data from publicly available genome-wide association studies (GWAS). Data concerning total hip replacements (THR, N = 319,037) and total knee replacements (TKR, N = 252,041) were sourced from the Genetics of Osteoarthritis (GO) Consortium. Stroke-related data were obtained from the International Stroke Genetics Consortium, encompassing any stroke (AS), any ischemic stroke (AIS), large vessel ischemic stroke (LV-IS), cardioembolic ischemic stroke (CE-IS), and small vessel ischemic stroke (SV-IS). Our primary causal inference method was the inverse variance weighted (IVW) approach, supplemented by weighted median and MR-Egger regression as secondary inference methods. We utilized the MR-PRESSO global test for outlier detection, Cochran's Q statistic to assess heterogeneity, and assessed the multiplicity and stability of our findings using p-values from MR-PRESSO and MR-Egger regressions, and the leave-one-out method, respectively.

Results

We identified significant genetic associations between THR and both AS (IVW p = 0.0001, OR = 1.08, 95% CI = 1.04-1.12) and AIS (IVW p = 0.0016, OR = 1.07, 95% CI = 1.03-1.12). Significant associations were also observed between TKR and AS (IVW p = 0.0002, OR = 1.08, 95% CI = 1.04-1.12), as well as AIS (IVW p = 0.0005, OR = 1.15, 95% CI = 1.06-1.24).

Conclusion

Our findings genetically support an increased risk of stroke following total hip and knee replacements. However, further studies are necessary to elucidate the specific mechanisms underlying stroke episodes post-replacement.

[Translated article] Risk of venous thromboembolism in thromboprophylaxis between aspirin and low molecular weight heparins after total hip arthroplasty or total knee arthroplasty: Systematic review and meta-analysis

INTRODUCTION

The aim of this study was to evaluate the efficacy of aspirin versus low molecular weight heparins (LMWH) for the prophylaxis of venous thromboembolism (VTE), deep vein thrombosis (DVT) and pulmonary embolism (PE) in patients undergoing total knee arthroplasty (TKA) and/or total hip arthroplasty (THA).

MATERIALS AND METHODS

Systematic review and meta-analysis. Sixteen studies were selected. The risk of VTE, DVT and PE were analysed. Mortality, risk of bleeding and surgical wound complications was also analysed.

RESULTS

248,461 patients were included. 176,406 patients with thromboprophylaxis with LMWH and 72,055 patients with aspirin thromboprophylaxis. There were no significant differences in the risk of VTE (OR=0.93; 95% CI: 0.69-1.26; p=0.64), DVT (OR=0.72; 95% CI: 0.43-1.20; p=0.21) or PE (OR=1.13; 95% CI: 0.86-1.49; p=0.38) between both groups. No significant differences were found in mortality (p=0.30), bleeding (p=0.22), or complications in the surgical wound (p=0.85) between both groups. These same findings were found in the sub-analysis of only randomised clinical trials (p>0.05).

CONCLUSIONS

No increased risk of PE, DVT, or VTE was found among patients with aspirin thromboprophylaxis versus patients with LMWH thromboprophylaxis. There was also no greater mortality, greater bleeding, or greater complications in the surgical wound found among patients with aspirin thromboprophylaxis versus patients with LMWH thromboprophylaxis.

Pharmacotherapy for Venous Thromboprophylaxis following Total Hip or Knee Arthroplasty: A Systematic Review and Network Meta-analysis

The optimal pharmacological prophylaxis for venous thromboembolism (VTE) after hip or knee arthroplasty is uncertain. We conducted a systematic review and network meta-analysis to compare the efficacy and safety of various medications. We searched multiple databases for randomized clinical trials (RCTs) comparing medications (including factor Xa inhibitors, factor IIa inhibitor, warfarin, unfractionated heparin [UFH], low-molecular-weight heparin [LMWH], aspirin, pentasaccharide) for VTE prophylaxis post-arthroplasty. Outcomes included any postoperative VTE identified with screening, major bleeding, and death. We used LMWH as the main comparator for analysis and performed trial sequential analysis (TSA) for each pairwise comparison. Certainty of evidence was assessed using GRADE (Grading of Recommendations, Assessments, Developments and Evaluations). We analyzed 70 RCTs (55,841 participants). Factor Xa inhibitors decreased postoperative VTE significantly compared with LMWH (odds ratio [OR]: 0.55, 95% confidence interval [CI]: 0.44-0.68, high certainty). Pentasaccharides probably reduce VTE (OR: 0.61, 95% CI: 0.36-1.02, moderate certainty), while the factor IIa inhibitor dabigatran may reduce VTE (OR: 0.75, 95% CI: 0.40-1.42, low certainty). UFH probably increases VTE compared with LMWH (OR: 1.31, 95% CI: 0.91-1.89, moderate certainty), and other agents like warfarin, aspirin, placebo, and usual care without thromboprophylaxis increase VTE (high certainty). Factor Xa inhibitors may not significantly affect major bleeding compared with LMWH (OR: 1.06, 95% CI: 0.81-1.39, low certainty). No medications had a notable effect on mortality compared with LMWH (very low certainty). TSA suggests sufficient evidence for the benefit of factor Xa inhibitors over LMWH for VTE prevention. Compared with LMWH and aspirin, factor Xa inhibitors are associated with reduced VTE after hip or knee arthroplasty, without an increase in bleeding and likely no impact on mortality.

Aspirin Compared to Other Thromboprophylactic Agents in Patients Following Total Hip Arthroplasty: A Literature Review

Total hip arthroplasty (THA) is a common but major surgery performed in the United Kingdom and around the globe. THA is associated with several postoperative complications, with one of the most common being venous thromboembolism (VTE) in the form of deep venous thrombosis (DVT) or pulmonary embolism (PE). VTE following orthopaedic surgery can have major consequences in terms of patient morbidity and may even cause mortality. It carries a significant cost to the health service, and thromboprophylactic agents are used to decrease the risk. Several different options are available for chemical thromboprophylaxis, including aspirin, low-molecular-weight heparin (LMWH), direct oral anticoagulants (DOACs), and warfarin. This study aims to review the literature to determine if aspirin is less superior to the other available chemical thromboprophylaxis in postoperative patients following THA. The primary outcome assessed in this review is rates of symptomatic 90-day VTE in the form of PE or DVT. A literature review was conducted using PubMed, Scopus, and Google Scholar using the following terms: 'Aspirin AND (low molecular weight heparin OR LMWH OR Enoxaparin OR Apixaban OR DOAC OR direct oral anticoagulant OR warfarin) AND (orthopaedic OR orthopedic) AND (Total hip replacement OR THR OR THA OR total hip arthroplasty) AND ('venous thromboembolism' OR VTE).' Aspirin appears to have promising results as thromboprophylaxis in cases of THA. However, it is still up for debate as to whether it is non-inferior to other forms of thromboprophylaxis.

Risk of venous thromboembolism in thromboprophylaxis between aspirin and low molecular weight heparins after total hip arthroplasty or total knee arthroplasty: Systematic review and meta-analysis

INTRODUCTION

The aim of this study was to evaluate the efficacy of aspirin versus low molecular weight heparins (LMWH) for the prophylaxis of venous thromboembolism (VTE), deep vein thrombosis (DVT) and pulmonary embolism (PE) in patients undergoing total knee arthroplasty (TKA) and/or total hip arthroplasty (THA).

MATERIALS AND METHODS

Systematic review and meta-analysis. Sixteen studies were selected. The risk of VTE, DVT and PE were analyzed. Mortality, risk of bleeding and surgical wound complications was also analyzed.

RESULTS

248,461 patients were included. 176,406 patients with thromboprophylaxis with LMWH and 72,055 patients with aspirin thromboprophylaxis. There were no significant differences in the risk of VTE (OR = 0.93; 95% CI: 0.69-1.26; P = .64), DVT (OR = 0.72; 95% CI: 0.43-1.20; P = .21) or PE (OR = 1.13; 95% CI: 0.86-1.49; P = .38) between both groups. No significant differences were found in mortality (P = .30), bleeding (P = .22), or complications in the surgical wound (P = .85) between both groups. These same findings were found in the sub-analysis of only randomized clinical trials (P>.05).

CONCLUSIONS

No increased risk of PE, DVT, or VTE was found among patients with aspirin thromboprophylaxis versus patients with LMWH thromboprophylaxis. There was also no greater mortality, greater bleeding, or greater complications in the surgical wound found among patients with aspirin thromboprophylaxis versus patients with LMWH thromboprophylaxis.

Global trends in research of venous thromboembolism associated with lower limb joint arthroplasty: A bibliometric analysis

This study aims to visualize publications related to venous thromboembolism (VTE) and lower limb joint arthroplasty to identify research frontiers and hotspots, providing references and guidance for further research. We retrieved original articles published from 1985 to 2022 and their recorded information from the Web of Science Core Collection. The search strategy used terms related to knee or hip arthroplasty and thromboembolic events. Microsoft Excel was used to analyze the annual publications and citations of the included literature. The rest of the data were analyzed using the VOSviewer, citespace and R and produced visualizations of these collaborative networks. We retrieved 3543 original articles and the results showed an overall upward trend in annual publications. The United States of America had the most significant number of publications (Np) and collaborative links with other countries. McMaster University had the greatest Np. Papers published by Geerts WH in 2008 had the highest total link strength. Journal of Arthroplasty published the most articles on the research of VTE associated with lower limb joint arthroplasty. The latest research trend mainly involved "general anesthesia" "revision" and "tranexamic acid." This bibliometric study revealed that the research on VTE after lower limb joint arthroplasty is developing rapidly. The United States of America leads in terms of both quantity and quality of publications, while European and Canadian institutions and authors also make significant contributions. Recent research focused on the use of tranexamic acid, anesthesia selection, and the VTE risk in revision surgeries.

Construction and validation of a predictive model for lower extremity deep vein thrombosis after total knee arthroplasty

The aim was to investigate the independent risk factors for lower extremity deep vein thrombosis (DVT) after total knee arthroplasty, and to establish a nomogram prediction model accordingly. Data were collected from total knee replacement patients from January 2022 to December 2023 in our hospital. Unifactorial and multifactorial logistic regression analyses were used to determine the independent risk factors for lower extremity DVT after total knee arthroplasty and to establish the corresponding nomogram. The receiver operating characteristic curves were plotted and the area under the curve was calculated, and the calibration curves and decision curves were plotted to evaluate the model performance. A total of 652 patients with total knee arthroplasty were included in the study, and 142 patients after total knee arthroplasty developed deep veins in the lower extremities, with an incidence rate of 21.78%. After univariate and multivariate logistic regression analyses, a total of 5 variables were identified as independent risk factors for lower extremity DVT after total knee arthroplasty: age > 60 years (OR: 1.70; 95% CI: 1.23-3.91), obesity (OR: 1.51; 95% CI: 1.10-1.96), diabetes mellitus (OR: 1.80; 95% CI: 1.23-2.46), D-dimer > 0.5 mg/L (OR: 1.47; 95% CI: 1.07-1.78), and prolonged postoperative bed rest (OR: 1.64; 95% CI: 1.15-3.44). the nomogram constructed in this study for lower extremity DVT after total knee arthroplasty has good predictive accuracy, which helps physicians to intervene in advance in patients at high risk of lower extremity DVT after total knee arthroplasty.

How I treat the co-occurrence of venous and arterial thromboembolism: anticoagulation, antiplatelet therapy, or both?

ABSTRACT

Arterial and venous thromboses are classically considered distinct disease states, with arterial thrombosis mediated predominantly by platelets and therefore, treated with antiplatelet therapy, and venous thrombosis mediated by the plasmatic coagulation system and treated with anticoagulation. However, co-occurrence of arterial and venous events is common, and there is increasing evidence of shared risk factors and pathophysiologic overlap. This presents a management challenge: does the patient with venous and arterial thrombosis, require anticoagulation, antiplatelet therapy, or both? Herein, we present a structured approach to the evaluation and management of patients with venous thrombosis who are also at risk for or have a history of an arterial thromboembolic event. We emphasize the importance of defining the indications for antithrombotic therapy, as well as the evaluation of factors that influence both thrombotic and bleeding risk, including disorder-specific and patient-specific factors, as well as the inherent risk balance of antithrombotic therapy regimens. We illustrate this approach in 4 cases, discussing the unique considerations and recent updates in the management of venous thrombosis, acute noncardioembolic ischemic stroke, coronary artery disease and acute myocardial infarction, and peripheral artery disease after revascularization.

American Association for the Surgery of Trauma/American College of Surgeons Committee on Trauma clinical protocol for postdischarge venous thromboembolism prophylaxis after trauma

ABSTRACT

Trauma patients are at an elevated risk for developing venous thromboembolism (VTE), which includes pulmonary embolism and deep vein thrombosis. In the inpatient setting, prompt pharmacologic prophylaxis is utilized to prevent VTE. For patients with lower extremity fractures or limited mobility, VTE risk does not return to baseline levels postdischarge. Currently, there are limited data to guide postdischarge VTE prophylaxis in trauma patients. The goal of these postdischarge VTE prophylaxis guidelines are to identify patients at the highest risk of developing VTE after discharge and to offer pharmacologic prophylaxis strategies to limit this risk.

Cost-effectiveness of enoxaparin versus aspirin in the prevention of venous thromboembolism after total hip or knee arthroplasty: an analysis from the CRISTAL cluster-randomized trial

Aims

The aim of this study was to evaluate the healthcare costs and benefits of enoxaparin compared to aspirin in the prevention of symptomatic venous thromboembolism (VTE) after total hip arthroplasty (THA) or total knee arthroplasty (TKA) using data from the CRISTAL trial.

Methods

This trial-based economic analysis reports value for money as incremental cost per quality-adjusted life-year (QALY) gained in 2022 Australian dollars, compared to a single threshold value of AUD$70,000 per QALY. Event costs were estimated based on occurrence of VTEs and bleeds, and on published guidelines for treatment. Unit costs were taken from Australian sources. QALYs were estimated using CRISTAL six-month follow-up data. Sensitivity analyses are presented that vary the cost of VTE treatment, and extend the analyses to two years.

Results

The CRISTAL trial found that enoxaparin was more effective than aspirin in preventing symptomatic VTE within 90 days of THA or TKA (risk difference 1.97% (95% confidence interval (CI) 0.54% to 3.41%; p = 0.007)). The additional cost after a THA or TKA was AUD$83 (95% CI 68 to 97) for enoxaparin, and enoxaparin resulted in an additional 0.002 QALYs (95% CI -0.002 to 0.005). Incremental cost per QALY gained was AUD$50,567 (95% CI 15,513, dominated) for enoxaparin. We can be 60% confident that the incremental cost per QALY does not exceed the willingness-to-pay threshold of AUD$70,000. Increasing the cost of VTE treatment and extension of costs and consequences to two years suggested greater confidence that enoxaparin is good value for money (70% and 63% confidence, respectively).

Conclusion

This analysis provides strong evidence that enoxaparin thromboprophylaxis following THA or TKA reduced VTEs, but weak evidence of net economic benefits over aspirin. If the value of avoiding VTEs is high, and there is a strong likelihood of VTE-related health impairments, we can be more confident that enoxaparin is cost-effective compared to aspirin.

Clinical outcomes after inferior vena cava resection for malignant disease. A single center experience of 51 vena cava resections

BACKGROUND AND OBJECTIVE

For tumors involving inferior vena cava (IVC), surgery with complete resection remains the first line treatment. Management of IVC after resection, either ligation without reconstruction or primary reconstruction, is debated. Our study aimed to evaluate type of venous reconstruction, anticoagulation management and morbidity.

METHODS

A French single center database of patients who underwent partial or total circumferencial resection of the IVC for malignant disease was analyzed. Inclusion criteria were any oncologic procedure for a retroperitoneal neoplasm requiring concomitant resection of the IVC with or without venous reconstruction with prosthesis. Exclusion criteria were surgery before year 2000. Data were descriptive and reverse Kaplan Meier was used for follow-up calculation. The endpoints were the rate of prosthetic reconstruction, the use of anticoagulation and the post-operative outcomes.

RESULTS

Fifty - one patients were included with a median duration of follow-up of 54.8 months. The majority of patients were men (56.9%). Median age of the population was 44.1 years. Most of the patients underwent surgery for primary testicular cancer and for sarcoma. Complete IVC resections were performed in 46 (90,2%) patients, 32 having a concomitant prosthetic replacement. Eight patients underwent aortic resection in the same operative time. Postoperative morbidity was 33.3%. Post-operative anticoagulation was done in 24 patients. At 1 month, four patients developed thrombosis in the prosthesis.

CONCLUSIONS

IVC resections are feasible and safe. Venous reconstruction and postoperative management were planned according to the preoperative imaging and intraoperative findings. We propose a decision-tree for peri-operative management and anticoagulation.

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.

The Use of Aspirin for Venous Thromboembolism Prophylaxis in Patients Who Have Morbid Obesity Undergoing Primary and Revision Total Joint Arthroplasty

BACKGROUND

Venous thromboembolism (VTE) poses a major clinical concern due to its life-threatening nature, and obese and morbidly obese patients are thought to be at an increased risk for VTE. The aims of this study were twofold; first, to explore VTE rates in patients who have a body mass index (BMI) > 40 undergoing primary and revision total joint arthroplasty, and second, to investigate aspirin (ASA) efficacy and safety.

METHODS

We identified all patients (n = 4,672) who had a BMI > 40 who underwent primary and revision total joint arthroplasty from 2016 to 2022 at a single academic tertiary care center. Patients were stratified by BMI groups: 40 to 44.9 (n = 3,462), 45 to 49.9 (n = 935), and 50+ (n = 275). The primary outcome was any VTE event within 90 days postoperatively. The secondary outcome consisted of wound complications within 90 days postoperatively.

RESULTS

The total VTE rate was 0.4% (n = 21) and did not differ statistically between the BMI groups (0.4 versus 0.4 versus 0.7%, P = .669). The VTEs consisted of 6 deep venous thromboses (DVTs), 14 pulmonary embolisms, and one concomitant deep venous thrombosis and pulmonary embolism. The VTE rates were not statistically different between patients who received aspirin 325 mg 0.5% (n = 9), aspirin 81 mg 0.2% (n = 1), aspirin + anticoagulant (AC) 0.5% (n = 6), and AC alone 0.4% (n = 5) (P = .954). In addition, wound complications did not differ significantly between patients who received ASA 325 mg, ASA 81mg, ASA + AC, or AC alone (1.6 versus 1.0 versus 1.8 versus 1.1%, P = .351).

CONCLUSIONS

The use of aspirin 325 and 81 mg was found to have similar VTE rates as aspirin + ACs and ACs alone, with no significant increase in wound complications. In patients who have a BMI > 40, the use of aspirin is a safe option for VTE prophylaxis and should be prescribed in the context of the patient who has other risk factors for VTE.

Prevention and control of venous thromboembolism after major orthopedic surgery through doctor-to-patient cultivation of musculoskeletal ability based on King's theory of goal attainment

OBJECTIVES

To explore the prevention and management of venous thromboembolism (VTE) following major orthopaedic surgery (MOS) by fostering doctor-to-patient cultivation of musculoskeletal ability, guided by King's theory of goal attainment.

METHODS

A cohort of patients (n = 116) undergoing MOS was selected for the study, and were divided into two groups: the regular group and the observation group, with patients in the regular group experiencing routine nursing care and management and those in the observation group undergoing musculoskeletal ability cultivation based on King's theory of goal attainment. Baseline data, limb vascular ultrasonography, coagulation function, Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) score, VTE prevention efficacy, Exercise of Self-care Ability Scale (ESCA) score, and nursing satisfaction were analysed comparatively.

RESULTS

There was no significant within-group difference in baseline data (P > 0.05). Following the interventions, the observation group demonstrated statistically significant reductions in the Musculoskeletal-Integrated Imaging Score, various dimensions of WOMAC scores, and D-dimer (D-D) levels (P < 0.05) both in comparison to their levels before interventions and to those observed in the regular group (P < 0.05). Additionally, the observation group exhibited increases in prothrombin time levels and various dimensions of ESCA scores (P < 0.05) post-intervention, surpassing the pre-intervention levels and those obtained in the regular group (P < 0.05). Furthermore, the observation group exhibited a significantly lower incidence of VTE (P < 0.05) and higher nursing satisfaction (P < 0.05) compared to the regular group.

CONCLUSIONS

Nursing intervention measures, utilizing doctor-to-patient cultivation of musculoskeletal ability based on King's theory of goal attainment, have demonstrated a significant clinical benefit for VTE prevention and control in post-MOS patients. This approach not only effectively prevented VTE in post MOS patients but also enhanced their satisfaction towards nursing care.

Over the Past Decade, Preoperative Anemia Has Become a Greater Predictor of Transfusions After Total Knee Arthroplasty

BACKGROUND

With advancements in perioperative blood management and the use of tranexamic acid, the rate of transfusions after total knee arthroplasty (TKA) has substantially decreased. As these principles are refined, other modifiable risk factors, such as preoperative anemia, may play an increasingly important role in transfusion risk for patients undergoing TKA.

METHODS

A multicenter, national database was utilized to identify patients undergoing TKA from 2010 to 2021. Anemia was defined by World Health Organization definitions as < 12 g/dL for women and < 13 g/dL for men. A predictive model was created using backwards elimination logistic regression to predict transfusion risk, controlling for demographic and medical covariates. The coefficient of anemia was then analyzed for each year. The trend over time was fitted with a best-fit linear regression equation.

RESULTS

There were 509,117 patients who underwent TKA, and had a mean age of 67 years (range, 18 to 89). There were 57,716 (11%) patients who were anemic preoperatively, and 15,426 (3%) of patients required a transfusion. Rate of transfusion decreased from 10.6% in 2010 to 0.6% in 2021. The odds ratio associated with anemia as a predictor of transfusion increased from 3.1 (95% confidence interval: 2.1 to 4.6) in 2010 to 14.0 (95% confidence interval: 8.9 to 24) in 2021.

CONCLUSIONS

The results of this study demonstrate that the importance of preoperative anemia as a predictor of transfusion has increased over the past decade as rates of transfusion have decreased. As perioperative blood management protocols improve, preoperative anemia should be considered an important focus of intervention to reduce the risk of transfusion prior to TKA.

LEVEL OF EVIDENCE

III.

Risk factors for venous thromboembolism after primary total joint arthroplasty: An analysis of 7511 Taiwanese patients

BACKGROUND

The need for thromboprophylaxis in Asian patients after primary total joint arthroplasty (TJA) remains inconclusive. We aimed to identify the risk factors for venous thromboembolism (VTE) events following primary TJA in a Taiwanese population.

METHODS

From January 2010 to December 2019, we studied 7511 patients receiving primary TJA from a single surgeon. We validated the incidence and risk factors for 30- and 90-day symptomatic VTE events, including age, sex, body mass index (BMI), smoking, medical comorbidities, VTE history, presence of varicose veins, total knee arthroplasty (TKA) vs total hip arthroplasty (THA), unilateral vs bilateral procedure and receipt of VTE prophylaxis, transfusion, and length of stay.

RESULTS

The incidence of 30- and 90-day symptomatic VTE events was 0.33% and 0.44%, respectively. Multivariate regression analysis showed that BMI ≥30 (adjusted odds ratio (aOR): 4.862, 95% CI, 1.776-13.313), bilateral TJA procedure (aOR: 2.665, 95% CI, 1.000-7.104), and presence of varicose veins (aOR: 9.946, 95% CI, 1.099-90.024) were associated with increased odds of 30-day symptomatic VTE events. Age ≥77 years (aOR, 2.358, 95% CI, 1.034-5.381) and BMI ≥30 (aOR: 2.832, 95% CI, 1.039-7.721) were associated with increased odds of 90-day symptomatic VTE events.

CONCLUSION

Age ≥77 years, BMI ≥30, bilateral TJA procedure, or presence of varicose veins may require pharmacological thromboprophylaxis because such patients have a higher risk of VTE after primary TJA.

Aspirin or enoxaparin for VTE prophylaxis after primary partial, total or revision hip or knee arthroplasty: A secondary analysis from the CRISTAL cluster randomized trial

BACKGROUND

This study compares aspirin to enoxaparin for symptomatic VTE prophylaxis within 90 days of any type of hip or knee arthroplasty performed for any diagnosis, in patients enrolled in the CRISTAL trial.

MATERIALS AND METHODS

CRISTAL was a cluster-randomised crossover, registry-nested non-inferiority trial across 31 hospitals in Australia. The primary publication was restricted to patients undergoing primary total hip or knee arthroplasty for a diagnosis of osteoarthritis. This report includes all enrolled patients undergoing hip or knee arthroplasty procedures (partial or total, primary or revision) performed for any indication. Hospitals were randomized to administer patients aspirin (100mg daily) or enoxaparin (40mg daily), for 35 days after hip arthroplasty and 14 days after knee arthroplasty. Crossover occurred after the patient enrolment target had been met for the first group. The primary outcome was symptomatic VTE within 90 days. Analyses were performed by randomization group.

RESULTS

Between April 20, 2019 and December 18, 2020, 12384 patients were enrolled (7238 aspirin group and 5146 enoxaparin). Of these, 6901 (95.3%) given aspirin and 4827 (93.8%) given enoxaparin (total 11728, 94.7%) were included in the final analyses. Within 90 days, symptomatic VTE occurred in 226 (3.27%) aspirin patients and 85 (1.76%) enoxaparin patients, significant for the superiority of enoxaparin (estimated treatment difference 1.85%, 95% CI 0.59% to 3.10%, p = 0.004). Joint-related reoperation within 90 days was lower in the enoxaparin group (109/4827 (2.26%) vs 171/6896 (2.47%) with aspirin, estimated difference 0.77%; 95% CI 0.06% to 1.47%, p = 0.03). There were no significant differences in the other secondary outcomes.

CONCLUSION

In patients undergoing hip or knee arthroplasty (of any type, performed for any indication) enrolled in the CRISTAL trial, aspirin compared to enoxaparin resulted in a significantly higher rate of symptomatic VTE and joint-related reoperation within 90 days. These findings extend the applicability of the CRISTAL trial results.

TRIAL REGISTRATION

Anzctr.org.au, identifier: ACTRN12618001879257.

Prevention of thromboembolism after a fracture: is aspirin enough?

Venous thromboembolism (VTE) is a serious complication that can arise during and after hospitalization, particularly following surgery under general anaesthesia. Particularly at risk are major orthopaedic surgical procedures such as elective knee or hip replacement and the treatment of hip fractures. In these patients, current guidelines recommend (low or low-moderate level of evidence) aspirin as a possible alternative to anticoagulant therapy for the prophylaxis of long-term venous thromboembolism after an initial period with anticoagulant drugs. Several randomized trials and meta-analyses demonstrate no significant differences in the risk of VTE when comparing aspirin with anticoagulants. However, it must be considered that most recommendations are based on elective orthopaedic surgery and that trials after fractures have excluded patients at high thrombotic risk. Consequently, the overall incidence of major clinical events (death and pulmonary embolism) was ∼1% with wide confidence margins in even large non-inferiority studies. The incidence of asymptomatic VTE, especially distal, appears to be higher with aspirin. Patient preference and lower costs could play an important role in the choice in favour of aspirin.

Perioperative Differences Between Outpatient and Inpatient Pathways Following Hip and Knee Arthroplasty

Background

Optimization of clinical pathways and logistics led to the introduction of outpatient joint arthroplasty of the hip and knee. Nevertheless, little is known about what these current protocols look like and how they differ from "standard" inpatient protocols. This study aimed to find preoperative, intraoperative, and postoperative differences between outpatient and inpatient pathways.

Methods

A questionnaire (ranging between 23 and 37 items) was developed and administered by email to orthopedic surgeons who were a member of the Dutch Hip Society and Dutch Knee Society. Survey response rate was 38% (N = 117).

Results

No significant differences were found in preoperative pathway characteristics. The administration regime for tranexamic acid significantly differed between outpatient and inpatient pathways (P < .001 and P = .002 for hip and knee arthroplasty, respectively), with outpatient pathways using a combined (eg, oral and intravenous) administration regime more frequently. The perioperative antibiotic prophylaxis regime also significantly differed between outpatient and inpatient pathways (P < .001 and P = .014, respectively), with outpatient pathways more frequently incorporating fewer antibiotic doses. Same-day postoperative mobilization significantly less often occurred if surgery took place later that day in inpatient hip arthroplasty pathways (24%; P = .034). Postoperative hemoglobin-check occurred significantly more often on indication in outpatient than in inpatient hip and knee arthroplasty pathways (∼75% vs ∼25%; P = .001).

Conclusions

Few intraoperative and postoperative differences in outpatient and inpatient pathways were found and probably mainly relied on logistical grounds. Nonetheless, findings suggested that outpatient pathways tended to be more up-to-date and innovative than inpatient pathways.

The 125th Anniversary of Aspirin-The Story Continues

The year 2024 marks the 125th anniversary of aspirin, still one of the most frequently used drugs worldwide. Despite its veritable age, it is still relevant in pharmacotherapy and its use has spread to new areas over time. Due to aspirin's multiple pharmacological actions unified in one single molecule (i.e., analgesic, antipyretic, anti-inflammatory, antithrombotic, and antiviral effects), it continues to attract considerable attention in the scientific community and is subject to intense basic and clinical research. In fact, recent results confirmed aspirin's potential role as an antiviral drug and as an agent that can block harmful platelet functions in inflammatory/immunological processes. These features may open up new horizons for this ancient drug. The future of aspirin looks, therefore, bright and promising. Aspirin is not yet ready for retirement; on the contrary, its success story continues. This 125th anniversary paper will concisely review the various therapeutic uses of aspirin with a particular emphasis on the latest research results and their implications (e.g., use as an antiviral agent). In addition, the reader is provided with future perspectives for this remarkable drug.

RANDOMIZED CLINICAL TRIAL OF ASPIRIN AS PROPHYLAXIS FOR THROMBOEMBOLISM IN HIP ARTHROPLASTY

Objective

This study aims to evaluate aspirin as a chemical prophylaxis (200 mg) in total hip arthroplasty.

Methods

the study compared two groups and used ultrasonography (USG) to screen for low-deep venous thrombosis. Group 1 received 600 mg (control), and Group 2 received 200 mg of (intervention), associated with the use of elastic compression stockings and early walking.

Results

fourteen patients were allocated to Group A (200mg), and 16 to Group B (600mg); in group A (200mg), 3 cases with thrombus below the popliteal vein were detected at the first USG examination. All of them are in the left lower limb (21.4%). In group B (600 mg), 5 cases were identified after the first exam (31.2%). All cases were asymptomatic and followed the protocol with prophylaxis only with Aspirin.

Conclusion

In the statistical data, there were no differences in the presence of thrombus between the 200- and 600 mg groups, which is credited to using low-dose aspirin in low doses (200mg). Hematimetric levels returned to baseline levels and suggested there was no chronic or acute bleeding related to the use of aspirin. The manuscript was prepared according to the CONSORT guideline 2010. Level of Evidence I; Longitudinal Randomized Comparative Clinical Study.

Compliance with Australian Orthopaedic Association guidelines does not reduce the risk of venous thromboembolism after total hip and knee arthroplasty

Preventing avoidable venous-thrombo-embolism (VTE) is a priority to improve patient and service outcomes after total hip and total knee arthroplasty (THA, TKA), but compliance with relevant clinical guidelines varies. This study aims to determine the degree to which prophylaxis was compliant with Australian Orthopaedic Association (AOA) VTE prophylaxis guidelines and whether non-compliance is associated with increased risk of VTE. A prospective multi-centre cohort study of adults with osteoarthritis undergoing primary TKA/THA was completed at 19 high-volume public and private hospitals. Data were collected prior to surgery and for one-year post-surgery. Logistic regression was undertaken to explore associations between non-compliance with AOA VTE prophylaxis guidelines and symptomatic 90-day VTE outcomes. Data were analysed for 1838 participants from 19 sites. The rate of non-compliance with all clinical guideline recommendations was 20.1% (N = 369), with 14.1% (N = 259) non-compliance for risk-stratified prophylaxis, 35.8% (N = 658) for duration, and 67.8% (N = 1246) for other general recommendations. Symptomatic VTE was experienced up to 90-days post-surgery by 48 people (2.6%). Overall guideline non-compliance (AOR = 0.93, 95%CI = 0.4 to 1.3, p = 0.86) was not associated with a lower risk of symptomatic 90-day VTE. Results were consistent when people with high bleeding risk were excluded (AOR = 0.94, 95%CI = 0.44 to 2.34, p = 0.89). Non-compliance with the AOA VTE prophylaxis guidelines was not associated with risk of 90-day VTE after arthroplasty. This counterintuitive finding is concerning and necessitates a rigorous review of the AOA VTE prevention clinical guideline.

Evaluating ChatGPT responses in the context of a 53-year-old male with a femoral neck fracture: a qualitative analysis

PURPOSE

The integration of artificial intelligence (AI) tools, such as ChatGPT, in clinical medicine and medical education has gained significant attention due to their potential to support decision-making and improve patient care. However, there is a need to evaluate the benefits and limitations of these tools in specific clinical scenarios.

METHODS

This study used a case study approach within the field of orthopaedic surgery. A clinical case report featuring a 53-year-old male with a femoral neck fracture was used as the basis for evaluation. ChatGPT, a large language model, was asked to respond to clinical questions related to the case. The responses generated by ChatGPT were evaluated qualitatively, considering their relevance, justification, and alignment with the responses of real clinicians. Alternative dialogue protocols were also employed to assess the impact of additional prompts and contextual information on ChatGPT responses.

RESULTS

ChatGPT generally provided clinically appropriate responses to the questions posed in the clinical case report. However, the level of justification and explanation varied across the generated responses. Occasionally, clinically inappropriate responses and inconsistencies were observed in the generated responses across different dialogue protocols and on separate days.

CONCLUSIONS

The findings of this study highlight both the potential and limitations of using ChatGPT in clinical practice. While ChatGPT demonstrated the ability to provide relevant clinical information, the lack of consistent justification and occasional clinically inappropriate responses raise concerns about its reliability. These results underscore the importance of careful consideration and validation when using AI tools in healthcare. Further research and clinician training are necessary to effectively integrate AI tools like ChatGPT, ensuring their safe and reliable use in clinical decision-making.

Comparison of efficacy and safety between aspirin and oral anticoagulants for venous thromboembolism prophylaxis after major orthopaedic surgery: a meta-analysis of randomized clinical trials

Background: venous thromboembolism (VTE) is one of the most common complications after major orthopaedic surgery. Recent studies have suggested that aspirin may also be effective in preventing VTE, but it is still controversial whether it can be routinely used. Objectives: To compare the efficacy and safety of aspirin against oral anticoagulants in the prevention of VTE following total hip arthroplasty (THA), total knee arthroplasty (TKA) or hip fracture surgery (HFS). Methods: Relevant publications have been obtained using electronic search databases such as PubMed, Embase, Web of Science, Cochrane Library, and Clinical Trials. gov. from inception to 20 July 2023. Only RCTs evaluating the efficacy and safety of aspirin compared with oral anticoagulants undergoing major orthopaedic surgery were included in the meta-analysis. The primary outcome reported was any VTE event (including deep vein thrombosis (DVT) and pulmonary embolism (PE)). Secondary outcomes included mortality, major bleeding (including gastrointestinal bleed, cerebrovascular hemorrhage, or any bleeding requiring a return to the theater), minor bleeding (ecchymosis, epistaxis, hematuria), and wound complications. The risk of bias for all included studies was assessed according to the Cochrane Collaboration's tool. Results: After screening 974 studies, 12 randomized clinical trials (RCTs) were included, involving 5,088 participants, including 2,540 participants in aspirin, 2,205 participants in rivaroxaban, and 323 participants in warfarin. Aspirin was found to be less effective than oral anticoagulants in thromboprophylaxis after major orthopedic surgery (RR = 1.206, 95% CI 1.053-1.383). After subgroup analysis according to the type of oral anticoagulant, the results showed that aspirin was similar to rivaroxaban and inferior to warfarin. Considering that the studies in the warfarin group were all conducted before 2000, our results need to be further confirmed. In addition, the aspirin group had a higher risk of VTE than the control group in other subgroups, including a follow-up time of ≤3 months, type of procedure as TKA, high-dose aspirin (≥650 mg qd), and no combined use of mechanical prophylaxis. In terms of safety events, aspirin did not show significant differences in major bleeding (RR = 0.952, 95% CI 0.499-1.815), all-cause mortality (RR = 1.208, 95% CI 0.459-3.177), and wound-related events (RR = 0.618, 95% CI 0.333-1.145) compared with oral anticoagulants, and aspirin was associated with a reduction in the risk of minor bleeding (RR = 0.685, 95% CI 0.552-0.850) events and total bleeding (RR = 0.726, 95% CI 0.590-0.892). Conclusion: Aspirin reduces bleeding risk after major orthopedic surgery compared with oral anticoagulants, but may sacrifice VTE prevention to some extent. Updated evidence is needed to analyze the thromboprophylaxis effects of aspirin in patients undergoing major orthopedic surgery. Systematic Review Registration: https://www.crd.york.ac.uk/prospero/display_record.php?RecordID=463481, identifier CRD42023463481.

Follow-up study of isolated calf muscular vein thrombosis for anticoagulant therapy after primary hip and knee arthroplasty

BACKGROUND

Although isolated calf muscular vein thrombosis (ICMVT) is commonly seen after hip and knee arthroplasty, no treatment guidelines for ICMVT after joint replacement are available. The purpose of this study was to evaluate the outcomes of patients with ICMVT for anticoagulant therapy at different time points after primary hip and knee arthroplasty.

METHODS

Patients with ICMVT after primary hip and knee arthroplasty were included in the study. Diagnosis was established with Doppler ultrasound. Patients were followed up clinically and with Doppler ultrasound at 1, 2, and 3 months. The outcomes were efficacy (complete resolution) and acceptability (hemorrhagic events). Anticoagulant therapy at curative dosage was prescribed for 1 month and was extended for 2 additional months in case of incomplete resolution at 1 month or if propagation was present. The chi-square test was used to compare the outcomes at different time points.

RESULTS

302 patients were taken hip and knee arthroplasty from January 2021 to May 2022, in which 51 patients presented with 51 ICMVTs postoperatively. The incidence of ICMVT was about 16.89%. Resolution of ICMVT was considered complete at 1, 2, and 3 months at 36.73%, 61.22%, and 91.84%, respectively, with significant differences among the time points (P < 0.05). All patients with ICMVT receiving anticoagulant therapy remained free of propagations and hemorrhagic events within 3 months.

CONCLUSION

Our findings provide new insights into the anticoagulant therapy for ICMVT after primary hip and knee arthroplasty, taking oral Rivaroxaban for 3 months is effective and safe, which contributes to provide the reference for clinical practice.

Prophylactic anticoagulation after minimally invasive hysterectomy for endometrial cancer: a cost-effectiveness analysis

OBJECTIVE

To determine our institutional rate of venous thromboembolism (VTE) following minimally invasive surgery for endometrial cancer and to perform a cost-effectiveness analysis of extended prophylactic anticoagulation after minimally invasive staging surgery for endometrial cancer.

METHODS

All patients with newly diagnosed endometrial cancer who underwent minimally invasive staging surgery from January 1, 2017 to December 31, 2020 were identified retrospectively, and clinicopathologic and outcome data were obtained through chart review. Event probabilities and utility decrements were obtained through published clinical data and literature review. A decision model was created to compare 28 days of no post-operative pharmacologic prophylaxis, prophylactic enoxaparin, and prophylactic apixaban. Outcomes included no complications, deep vein thrombosis (DVT), pulmonary embolism, clinically relevant non-major bleeding, and major bleeding. We assumed a willingness-to-pay threshold of $100 000 per quality-adjusted life year (QALY) gained.

RESULTS

Three of 844 patients (0.36%) had a VTE following minimally invasive staging surgery for endometrial cancer. In this model, no pharmacologic prophylaxis was less costly and more effective than prophylactic apixaban and prophylactic enoxaparin over all parameters examined. When all patients were assigned prophylaxis, prophylactic apixaban was both less costly and more effective than prophylactic enoxaparin. If the risk of DVT was ≥4.8%, prophylactic apixaban was favored over no pharmacologic prophylaxis. On Monte Carlo probabilistic sensitivity analysis for the base case scenario, no pharmacologic prophylaxis was favored in 41.1% of iterations at a willingness-to-pay threshold of $100 000 per QALY.

CONCLUSIONS

In this cost-effectiveness model, no extended pharmacologic anticoagulation was superior to extended prophylactic enoxaparin and apixaban in clinically early-stage endometrial cancer patients undergoing minimally invasive surgery. This model supports use of prophylactic apixaban for 7 days post-operatively in select patients when the risk of DVT is 4.8% or higher.

Dose-response association of benzodiazepine use and development of deep vein thrombosis

Benzodiazepines have sedative effects that cause reduced activity in users and may increase the risk of deep vein thrombosis. However, few studies have examined this potential risk of benzodiazepine use. This study examined the association between benzodiazepine use and the risk of deep vein thrombosis (DVT) in adults in Taiwan using a longitudinal health insurance database. The study population included 12,546 individuals with DVT and 50,184 matched controls. Results showed that benzodiazepine use was associated with an increased risk of DVT occurrence (adjusted odds ratio [aOR]: 1.66; 95 % CI, 1.54-1.79; P <0.001), with a dose-response relationship. Patients with a higher defined daily dose had a higher risk of DVT, with ORs of 1.65-, 2.09-, and 2.16-fold higher for those with an average benzodiazepine dose of <0.5, 0.5-0.9, or ≥1 (DDD/day), respectively, compared to nonbenzodiazepine users. Stratification by age, sex, and follow-up duration yielded similar results. This study highlights the need to evaluate the association and benefits of benzodiazepine prescription to decrease the risk of DVT development.

Current Evidence and Expert Opinion on Thromboprophylaxis After Total Knee and Hip Replacement

An effective anticoagulant provides a balance between the risk for venous thromboembolism (VTE) and bleeding and is crucial in achieving optimal clinical outcomes in patients undergoing total hip replacement (THR) and total knee replacement (TKR) surgeries. We performed a review of the literature on thromboprophylaxis for patients undergoing total hip or knee replacement. This review article summarizes current guidelines and evidence for anticoagulation along with the expert opinion about pharmacological VTE prophylaxis, particularly non-Vitamin K antagonist oral anticoagulants (NOACs), for patients after total hip or knee replacement. Aspirin for VTE prophylaxis after TKR/THR has been controversial and most of the evidence is reported from observational research. Although the guidelines do not recommend any specific thromboprophylaxis agent, available evidence suggests that NOACs are as effective as low molecular weight heparins (LMWHs) in preventing VTE. Oral administration and the lack of dose monitoring make NOACs easy to use in outpatient settings in cases with challenging treatment compliances. They can be used for two weeks after TKR and five weeks after THR - six weeks after TKR and THR to cover the at-risk period for VTE post-discharge. Owing to the lack of evidence for a head-to-head comparison of NOACs, an anticoagulant with better efficacy and safety may be suggested in special patient populations (elderly, obese patients, or those with renal dysfunction). The expert opinion on pharmacological VTE prophylaxis provided in this article could address some gaps in the management of anticoagulation in patients with total hip or knee replacement.

Venous Thromboembolism in Total Hip and Total Knee Arthroplasty

Importance

The optimal pharmacologic thromboprophylaxis agent after total hip and total knee arthroplasty is uncertain and consensus is lacking. Quantifying the risk of postoperative venous thromboembolism (VTE) and bleeding and evaluating comparative effectiveness and safety of the thromboprophylaxis strategies can inform care.

Objective

To quantify risk factors for postoperative VTE and bleeding and compare patient outcomes among pharmacological thromboprophylaxis agents used after total hip and knee arthroplasty.

Design, Setting, and Participants

This retrospective cohort study used data from a large health care claims database. Participants included patients in the United States with hip or knee arthroplasty and continuous insurance enrollment 3 months prior to and following their surgical procedure. Patients were excluded if they received anticoagulation before surgery, received no postsurgical pharmacological thromboprophylaxis, or had multiple postsurgery thromboprophylactic agents. In a propensity-matched analysis, patients receiving a direct oral anticoagulant (DOAC) were matched with those receiving aspirin.

Exposures

Aspirin, apixaban, rivaroxaban, enoxaparin, or warfarin.

Main Outcomes and Measures

The primary outcome was 30-day cumulative incidence of postdischarge VTE. Other outcomes included postdischarge bleeding.

Results

Among 29 264 patients included in the final cohort, 17 040 (58.2%) were female, 27 897 (95.2%) had inpatient admissions with median (IQR) length of stay of 2 (1-2) days, 10 948 (37.4%) underwent total hip arthroplasty, 18 316 (62.6%) underwent total knee arthroplasty; and median (IQR) age was 59 (55-63) years. At 30 days, cumulative incidence of VTE was 1.19% (95% CI, 1.06%-1.32%) and cumulative incidence of bleeding was 3.43% (95% CI, 3.22%-3.64%). In the multivariate analysis, leading risk factors associated with increased VTE risk included prior VTE history (odds ratio [OR], 5.94 [95% CI, 4.29-8.24]), a hereditary hypercoagulable state (OR, 2.64 [95% CI, 1.32-5.28]), knee arthroplasty (OR, 1.65 [95% CI, 1.29-2.10]), and male sex (OR, 1.34 [95% CI, 1.08-1.67]). In a propensity-matched cohort of 7844 DOAC-aspirin pairs, there was no significant difference in the risk of VTE in the first 30 days after the surgical procedure (OR, 1.14 [95% CI, 0.82-1.59]), but postoperative bleeding was more frequent in patients receiving DOACs (OR, 1.36 [95% CI, 1.13-1.62]).

Conclusions and Relevance

In this cohort study of patients who underwent total hip or total knee arthroplasty, underlying patient risk factors, but not choice of aspirin or DOAC, were associated with postsurgical VTE. Postoperative bleeding rates were lower in patients prescribed aspirin. These results suggest that thromboprophylaxis strategies should be patient-centric and tailored to individual risk of thrombosis and bleeding.

Apply Anticoagulants after Discharge not Benefit to the Incidence of Symptomatic Thrombus in High-Altitude Areas: A Retrospective Study

OBJECTIVE

Many guidelines indicate that continuous use of anticoagulant drugs reduces the incidence of venous thrombus (VT), but no studies show the effect on the incidence of symptomatic venous thrombus (SVT) in total knee arthroplasty (TKA) patients after discharge. This study aimed to investigate whether it is necessary to apply anticoagulants to TKA patients after discharge.

METHODS

Patients who met the exclusion criteria requirement, underwent TKA by the same surgical team and received anticoagulant therapy after the operation were eligible for the study. Finally, a total of 567 TKA patients were recruited as participants. The patients were divided into two groups. The patients in group A were taken low molecular heparin for 5-10 days after surgery, which included but was not limited to low molecular weight heparin calcium injection (0.4 mL, ih, Qd), calcium dioxin injection (0.6 mL, ih, Qd), or enoxaparin sodium injection (0.4 mL, ih, Qd), and the patients needed to continue oral anticoagulant drug (10 mg, po, Qd) for 7-21 days after discharge. The patients in group B only took low molecular heparin 5-10 days after surgery and no treatment after discharge. The baseline characteristics of patients, total complications of SVT include lower limb vascular pain (LLVP), lower limb vascular pain no fester (LLVPNF), lower limbs swelling (LLS), lower limb fester (LLF), and death by thrombosis (DT), bleeding and mortality following discharged were compared between two groups.

RESULTS

The study showed that the incidence of SVT patients had no significant difference between the two groups (p = 0.489). Moreover, the incidence of LLVP (p = 0.265), LLS (p = 0.84), LLVPNF (p = 0.213), LLF (p = 0.907), DT (p = 0.907), death from other causes, and bleeding (p = 0.323) had no significant differences between the two groups. However, the incidence of SVT in patients with smoking (p = 0.0001 or 0.0011) or drinking (p = 0.0002 or 0.0001) was significantly increased.

CONCLUSION

There is not enough evidence showing that the TKA patients given anticoagulants after discharge had benefits in decreasing the risk of SVT. Furthermore, smoking and drinking would significantly increase the risk of SVT in TKA patients.

A meta-analysis on the association between SSRIs and blood pressure in patients with CVD and depression

OBJECTIVE

This meta-analysis aimed to explore the association between selective serotonine reuptake inhibitors (SSRIs) and blood pressure in patients with cardiovascular disease (CVD) and depression.

METHOD

This study was registered on PROSPERO (CRD42022368655) and conducted in accordance with PRISMA 2020. The databases included PubMed, Web of Science, and EMBASE. The inclusion date was from the inception date through Oct. 26, 2022.Review Manager version 5.3 and Stata version 12.0 were used for data analysis.

RESULTS

This meta-analysis included six studies, and a total number of 149 patients with CVD and depression . In the group analysis, SSRIs treatment had no effect on the systolic blood pressure (SBP) (MD = 1.01, 95%CI:-2.88, 4.90, P = 0.61) and diastolic blood pressure (DBP) (MD = 0.64, 95%CI:-1.03, 2.31, P = 0.45). In the subgroup analysis, SSRIs treatment had no effect on SBP for patients with hypertension (MD = -8.02, 95%CI:-16.84, 0.81, P = 0.08), and patients with other CVD (MD = 3.18, 95%CI:-1.15, 7.52, P = 0.15). For patients with hypertension, SSRIs treatment significantly lowered DBP (MD = -5.75, 95%CI:-10.84, -0.67, P = 0.03). But SSRIs treatment had no impact on DBP for patients with other CVD (MD = 1.41, 95%CI:-0.36, 3.18, P = 0.12). Subgroup analysis of the treatment period and the country had no significant impact on SBP and DBP. In the sensitivity analysis, there was no significant change after omitting one study in both SBP and DBP group analysis. Egger's test showed no publication bias of SBP (P = 0.183) and DBP group analysis (P = 0.392).

CONCLUSION

SSRIs help to lower DBP in hypertensive patients with depression. The potential pathophysiological mechanisms may lie in serotonin function, sympathetic activation and genetic heterogeneity. Further clinic and experimental researches need to be conducted on SSRIs and blood pressure.

The silent killer: Previously undetected pulmonary emboli that result in death after discharge

INTRODUCTION

Pulmonary embolism (PE) is a recognized cause of death in hospitalized trauma patients, yet less is known about PE after discharge.

PATIENTS & METHODS

All post-discharge, autopsy-demonstrated, fatal PE resulting from trauma within a large US county over six years were analyzed. Counts, percentages, mean values, SD, and IQR were calculated for all variables.

RESULTS

1848 trauma deaths were reviewed, of which 85% had an autopsy. Eighty-five patients died from PE after discharge from their initial injury. 53% were initially treated at non-trauma centers, and 9% did not seek medical assistance. 75% were injured by falling, and most injuries occurred in the lower extremities. 86% had an ISS <16, but 87% needed assistance or were bed-bound after injury, despite 75% having no mobility limitations before the injury. 53% died within one month of injury, and 91% within the first year. Before death, only 11% were prescribed chemical thromboprophylaxis or an antiplatelet agent, and only 8% were diagnosed with venous thromboembolism before death.

CONCLUSIONS

Fatal PE after discharge typically occurred following activity-limiting lower extremity injuries with an ISS<16.

The efficacy and safety of aspirin in preventing venous thrombosis in major orthopedic surgery: An updated meta-analysis of randomized controlled trials

BACKGROUND

Major orthopedic surgery, including hip and knee replacement and lower extremity trauma fractures surgery, is associated with a high risk of venous thromboembolism (VTE), especially proximal deep vein thrombosis (DVT), and pulmonary embolism (PE), and is linked with high morbidity and mortality rates. Chemical anticoagulation is routinely used to prevent VTE, with previous meta-analyses reporting on the efficacy and safety of aspirin and other anticoagulants, however, opinions are divided. In the past 2 years, several large randomized controlled trials have been published, therefore, we reanalyzed aspirin efficacy and safety when compared with other anticoagulants in preventing VTE in major orthopedic surgery.

METHODS

Using PubMed, The Cochrane Library, Embase, and Web of Science databases, we conducted a RCT search in August 2023. The main outcomes included VTE, proximal DVT or PE. Additional outcomes included bleeding events, wound complications, wound infections, blood transfusions, and death events.

RESULTS

In total, 17 eligible articles, involving 29,522 patients (15,253 aspirin vs 14,269 other anticoagulant cases), were included. Primary outcomes showed that VTE incidence was more high in the aspirin group when compared with other anticoagulants (risk ratio [RR] = 1.45, 95% confidence interval [CI] = 1.18-1.77, P = .0004) and proximal in the aspirin group the DVT and/or PE incidence was significantly higher in the aspirin group when compared with other anticoagulants (RR = 1.19, 95% CI = 1.02-1.39, P = .03). No significant secondary outcome differences were identified in the aspirin group when compared with other anticoagulants (bleeding events [RR] = 0.83, 95% CI = 0.63-1.10, P = .20); wound complications (RR = 0.45, 95% CI = 0.20-1.04, P = .06); wound infection (RR = 1.08, 95% CI = 0.85-1.38, P = .53); blood transfusion events (RR = 1.00, 95% CI = 0.84-1.19, P = 1.00) and death events (RR = 1.11, 95% CI = 0.78-1.57, P = .55).

CONCLUSIONS

Our updated meta-analysis showed that aspirin was inferior to when compared with other anticoagulants in VTE-related orthopedic major surgery, including proximal DVT and/or PE, and was more likely to form VTE. No differences between groups were identified for bleeding, wound complications, wound infections, transfusion, or death events.

Intravenous tranexamic acid is associated with an increased risk of pulmonary embolism following sarcoma resection

INTRODUCTION

Tranexamic acid (TXA) is an antifibrinolytic drug that has been shown to reduce blood loss following surgery. The use of TXA during orthopedic procedures has gained widespread acceptance, with multiple clinical studies demonstrating no increase in thrombotic complications. While TXA has been shown to be safe and effective for several orthopedic procedures, its use in orthopedic sarcoma surgery is not well established. Cancer-associated thrombosis remains a significant cause of morbidity and mortality in patients with sarcoma. It is unknown if intraoperative TXA use will increase the risk of developing a postoperative thrombotic complication in this population. This study aimed to compare the risk of postoperative thrombotic complications in patients who received TXA during sarcoma resection to patients who did not receive TXA.

METHODS

A retrospective review was performed of 1099 patients who underwent resection of a soft tissue or bone sarcoma at our institution between 2010 and 2021. Baseline demographics and postoperative outcomes were compared between patients who did and did not receive intraoperative TXA. We evaluated 90-day complication rates, including: deep venous thrombosis (DVT), pulmonary embolism (PE), myocardial infarction (MI), cerebrovascular accident (CVA), and mortality.

RESULTS

TXA was used more commonly for bone tumors (p < 0.001), tumors located in the pelvis (p = 0.004), and larger tumors (p < 0.001). Patients who received intraoperative TXA were associated with a significant increase in developing a postoperative DVT (odds ratio [OR]: 2.22, p = 0.036) and PE (OR: 4.62, p < 0.001), but had no increase in CVA, MI, or mortality (all p > 0.05) within 90 days of surgery, following univariate analysis. Multivariable analysis confirmed that TXA was independently associated with developing a postoperative PE (OR: 10.64, 95% confidence interval: 2.23-50.86, p = 0.003). We found no association with DVT, MI, CVA, or mortality within 90 days postoperatively, following intraoperative TXA use.

CONCLUSION

Our results demonstrate a higher associated risk of PE following TXA use in sarcoma surgery and caution is warranted with TXA use in this patient population.

Venous Thromboembolism Prophylaxis in Major Orthopedic Surgeries and Factor XIa Inhibitors

Venous thromboembolism (VTE), comprising pulmonary embolism (PE) and deep vein thrombosis (DVT), poses a significant risk during and after hospitalization, particularly for surgical patients. Among various patient groups, those undergoing major orthopedic surgeries are considered to have a higher susceptibility to PE and DVT. Major lower-extremity orthopedic procedures carry a higher risk of symptomatic VTE compared to most other surgeries, with an estimated incidence of ~4%. The greatest risk period occurs within the first 7-14 days following surgery. Major bleeding is also more prevalent in these surgeries compared to others, with rates estimated between 2% and 4%. For patients undergoing major lower-extremity orthopedic surgery who have a low bleeding risk, it is recommended to use pharmacological thromboprophylaxis with or without mechanical devices. The choice of the initial agent depends on the specific surgery and patient comorbidities. First-line options include low-molecular-weight heparins (LMWHs), direct oral anticoagulants, and aspirin. Second-line options consist of unfractionated heparin (UFH), fondaparinux, and warfarin. For most patients undergoing knee or hip arthroplasty, the initial agents recommended for the early perioperative period are LMWHs (enoxaparin or dalteparin) or direct oral anticoagulants (rivaroxaban or apixaban). In the case of hip fracture surgery, LMWH is recommended as the preferred agent for the entire duration of prophylaxis. However, emerging factor XI(a) inhibitors, as revealed by a recent meta-analysis, have shown a substantial decrease in the occurrence of VTE and bleeding events among patients undergoing major orthopedic surgery. This discovery poses a challenge to the existing paradigm of anticoagulant therapy in this specific patient population and indicates that factor XI(a) inhibitors hold great promise as a potential strategy to be taken into serious consideration.

The impact of adopting low-molecular-weight heparin in place of aspirin as routine thromboprophylaxis for patients with hip fracture

PURPOSE OF THE STUDY

In 2010, the National Institute for Health and Care Excellence (NICE) recommended the use of anticoagulants rather than aspirin as pharmacological thromboprophylaxis after hip fracture. We examine the impact of implementing this change in guidance on the clinical incidence of deep vein thrombosis (DVT).

STUDY DESIGN

Demographic, radiographic and clinical data were retrospectively collected for 5039 patients admitted to a single tertiary centre in the UK for hip fracture between 2007 and 2017. We calculated rates of lower-limb DVT and examined the impact of the June 2010 change of departmental policy, from use of aspirin to use of low-molecular-weight heparins (LMWH) in hip fracture patients.

RESULTS

Doppler scans were performed in 400 patients in the 180 days after a hip fracture, and identified 40 ipsilateral and 14 contralateral DVTs (p<0.001). The rate of DVT reduced significantly following the 2010 change in departmental policy from aspirin to LMWH in these patients (1.62% vs 0.83%, p<0.05).

CONCLUSIONS

The rate of clinical DVT halved following the change from aspirin to LMWH for pharmacological thromboprophylaxis, but the number needed to treat was 127. A figure of <1% for the incidence of clinical DVT in a unit that routinely uses LMWH monotherapy following hip fracture provides a context for discussions of alternative strategies, and for power calculations for future research. These figures are important to policy makers and to researchers as they will inform the design of the comparative studies on thromboprophylaxis agents for which NICE has called.

Comparison of the Efficacy and Safety of Aspirin and Low-Molecular-Weight Heparin in Patients With a Fracture: A Meta-Analysis

The aim of this study is to compare the efficacy and safety of aspirin and low-molecular-weight heparin (LMWH) in preventing thromboembolic events in patients with fractures. The present meta-analysis was reported according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. We searched EMBASE, PubMed, and EBSCO to find articles comparing aspirin and LMWH in patients with orthopedic trauma from inception to April 15, 2023. Limits were set to studies published in the English language only. Outcomes assessed in this meta-analysis included VTE and all-cause mortality. VTE can manifest as deep venous thrombosis (DVT) and pulmonary embolism. For safety analysis, rates of wound complication, infection, and bleeding complications were compared between the two study groups. A total of three studies were included in this meta-analysis enrolling 12884 patients. The study found no significant difference between the two groups in the risk of DVT and pulmonary embolism, and aspirin was non-inferior to LMWH for the prevention of all-cause mortality in patients. Additionally, no significant safety risk was associated with aspirin thromboprophylaxis. These findings suggest that inexpensive over-the-counter aspirin is as effective as LMWH in terms of safety and efficacy profile, making it a feasible option to consider in clinical practice.

Thirty day low-dose versus regular-dose aspirin for venous thromboembolism prophylaxis in primary total joint arthroplasty

BACKGROUND

The optimal dosing of aspirin (ASA) monotherapy for prophylaxis after total joint arthroplasty is debatable. The objective of this study was to compare two ASA regimens with regards to symptomatic deep venous thrombosis (DVT), pulmonary embolism (PE), bleeding, and infection 90 days after primary total hip arthroplasty (THA) and total knee arthroplasty (TKA).

METHODS

We retrospectively identified 625 primary THA and TKA surgeries in 483 patients who received ASA for 4 weeks post-op. 301 patients received 325 mg once daily (QD) and 324 patients received 81 mg twice daily (BID). Patients were excluded if they were minors, had a prior venous thromboembolism (VTE), had ASA allergy, or received other VTE prophylaxis drugs.

RESULTS

There was a significant difference in rate of bleeding and suture reactions between the two groups. Bleeding was 7.6% for 325 mg QD and 2.5% for 81 mg BID (p = .0029 Χ2, p = .004 on multivariate logistic regression analysis). Suture reactions were 3.3% for 325 mg QD and 1.2% for 81 mg BID (p = .010 Χ2, p = .027 on multivariate logistic regression analysis). Rates of VTE, symptomatic DVT, and PE were not significantly different. The incidence of VTE was 2.7% for 325 mg QD and 1.5% for 81 mg BID (p = .4056). Symptomatic DVT rates were 1.6% for 325 mg QD and 0.9% for 81 mg BID (p = .4139). Deep infection was 1.0% for 325 mg QD and 0.31% for 81 mg BID (p = .3564).

CONCLUSION

Low-dose ASA in patients with limited comorbidities undergoing primary THA and TKA is associated with significant lower rates of bleeding and suture reactions than high dose ASA. Low-dose ASA was not inferior to higher dose ASA for the prevention of VTE, wound complications, and infection 90 days postoperatively.

Statistical Fragility of Venous Thromboembolism Prophylaxis Following Total Joint Arthroplasty

Background

Statistical fragility is a quantitative measure of the robustness of the statistical conclusions drawn in a study. Although statistical fragility has been comprehensively evaluated in the arthroplasty literature, the statistical fragility of large-scale randomized trials evaluating venous thromboembolism (VTE) prophylaxis has not been evaluated. The purpose of this study was to determine the utility of applying the fragility index (FI) and the fragility quotient (FQ) analysis to randomized controlled trials (RCTs) evaluating VTE prophylaxis following total joint arthroplasty.

Methods

A systematic review was performed by searching multiple databases to identify RCTs that evaluated VTE prophylaxis following total joint arthroplasty from 2000 to 2020. The FI was determined by manipulating each reported dichotomous outcome event until a reversal of significance was appreciated with 2 × 2 contingency tables. The associated FQ was determined by dividing the FI by the sample size.

Results

Thirty-two RCTs were ultimately included for analysis. The overall FI incorporating all 32 RCTs was only 7 (interquartile range 3-9), suggesting that the reversal of only 7 events is required to change study significance. The associated FQ was determined to be 0.01. Of the RCTs that reported lost-to-follow-up data, the majority of studies had lost-to-follow-up numbers greater than 7.

Conclusions

Our findings suggest that RCTs evaluating VTE prophylaxis following total hip arthroplasty and total knee arthroplasty may lack statistical stability as few outcome events are required to reverse the significance of outcomes. Future randomized trials should consider reporting FI and FQ along with the P value analysis to provide better context to the integrity of statistical stability.

Trends of Venous Thromboembolism After Total Hip Arthroplasty in the United States: Analysis From 2011 to 2019

BACKGROUND

In 2011, the American Academy of Orthopaedic Surgeons released a Clinical Practice Guideline` that recommended routine venous thromboembolism (VTE) prophylaxis after total joint arthroplasty. The purpose of this study was to examine (1) the change in the incidence of 90-day VTE, deep vein thrombosis, and pulmonary embolism, (2) the change in the utilization of antithrombotic agents; and (3) the change in the economic burden associated with VTE after total hip arthroplasty (THA) from 2011 to 2019.

METHODS

National, administrative claims data from 2011 to 2019 were used to identify patients who underwent primary THA for osteoarthritis. Exclusions entailed liver pathology, coagulopathy, malignancy, or those on prior prescribed blood thinners before THA. Multivariable regression was used, controlling for age and Charlson Comorbidity Index for all years, with 2011 as the reference year.

RESULTS

From 2011 to 2019, there was a significant reduction in 90-day VTE rates after THA, with a significant reduction in deep vein thrombosis and pulmonary embolism during this time frame as well. Of the antithrombotic agents prescribed after THA, the utilization of prescribed aspirin significantly increased and that of nonaspirin anticoagulants significantly decreased. Among nonaspirin anticoagulants, the utilization of direct factor Xa inhibitors and direct thrombin inhibitors significantly increased. The added reimbursements associated with VTE after THA significantly decreased during this period.

CONCLUSION

Since 2011, the incidence and economic burden associated with VTE after THA have significantly declined. In addition, there has been an increase in prescription aspirin and direct oral anticoagulants.

LEVEL OF EVIDENCE

Therapeutic, III.