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. Cite this article: Bone Joint J 2024;106-B(6):589–595

Aims. The optimal management of an infrapopliteal deep venous thrombosis (IDVT) following total knee arthroplasty (TKA) remains unknown. The risk of DVT propagation and symptom progression must be balanced against potential haemorrhagic complications associated with administration of anticoagulation therapy. The current study reports on a cohort of patients diagnosed with IDVT following TKA who were treated with aspirin, followed closely for development of symptoms, and scanned with ultrasound to determine resolution of IDVT. Methods. Among a cohort of 5,078 patients undergoing TKA, 532 patients (695 TKAs, 12.6%) developed an IDVT between 1 January 2014 to 31 December 2019 at a single institution, as diagnosed using Doppler ultrasound at the first postoperative visit. Of the entire cohort of 532 patients with IDVT, 91.4% (486/532) were treated with aspirin (325 mg twice daily) and followed closely. Repeat lower limb ultrasound was performed four weeks later to evaluate the status of IDVT. Results. Follow-up Doppler ultrasound was performed on 459/486 (94.4%) patients and demonstrated resolution of IDVT in 445/459 cases (96.9%). Doppler diagnosed propagation of IDVT to the popliteal vein had occurred in 10/459 (2.2%) cases. One patient with an IDVT developed a pulmonary embolus six weeks postoperatively. Conclusion. The results of this study demonstrate a low rate of IDVT propagation in patients managed with aspirin. Additionally, no significant bleeding episodes, wound-related complications, or other adverse events were noted from aspirin therapy. Cite this article: Bone Joint J 2021;103-B(6 Supple A):18–22

Aims. There is uncertainty regarding the optimal means of thromboprophylaxis following total hip and knee arthroplasty (THA, TKA). This systematic review presents the evidence for acetylsalicylic acid (aspirin) as a thromboprophylactic agent in THA and TKA and compares it with other chemoprophylactic agents. Materials and Methods. A search of literature published between 2004 and 2014 was performed in accordance with Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. A total of 13 studies were eligible for inclusion. Results. Evidence from one good quality randomised controlled trial (RCT) showed no difference in rates of venous thrombo-embolism (VTE) in patients given aspirin or low molecular weight heparin (LMWH) following TKA. There was insufficient evidence from trials with moderate to severe risk of bias being present to suggest aspirin is more or less effective than LMWH, warfarin or dabigatran for the prevention of VTE in TKA or THA. Compared with aspirin, rates of asymptomatic deep vein thrombosis (DVT) in TKA may be reduced with rivaroxaban but insufficient evidence exists to demonstrate an effect on incidence of symptomatic DVT. Compared with aspirin there is evidence of more wound complications following THA and TKA with dabigatran and in TKA with rivaroxaban. Some studies highlighted concerns over bleeding complications and efficacy of aspirin. Conclusion. The results suggest aspirin may be considered a suitable alternative to other thromboprophylactic agents following THA and TKA. Further investigation is required to fully evaluate the safety and efficacy of aspirin. Cite this article: Bone Joint J 2016;98-B:1056–61

The number of arthroplasties being performed increases each year. Patients undergoing an arthroplasty are at risk of venous thromboembolism (VTE) and appropriate prophylaxis has been recommended. However, the optimal protocol and the best agent to minimise VTE under these circumstances are not known. Although many agents may be used, there is a difference in their efficacy and the risk of bleeding. Thus, the selection of a particular agent relies on the balance between the desire to minimise VTE and the attempt to reduce the risk of bleeding, with its undesirable, and occasionally fatal, consequences. Acetylsalicylic acid (aspirin) is an agent for VTE prophylaxis following arthroplasty. Many studies have shown its efficacy in minimising VTE under these circumstances. It is inexpensive and well-tolerated, and its use does not require routine blood tests. It is also a ‘milder’ agent and unlikely to result in haematoma formation, which may increase both the risk of infection and the need for further surgery. Aspirin is also unlikely to result in persistent wound drainage, which has been shown to be associated with the use of agents such as low-molecular-weight heparin (LMWH) and other more aggressive agents. The main objective of this review was to summarise the current evidence relating to the efficacy of aspirin as a VTE prophylaxis following arthroplasty, and to address some of the common questions about its use. . There is convincing evidence that, taking all factors into account, aspirin is an effective, inexpensive, and safe form of VTE following arthroplasty in patients without a major risk factor for VTE, such as previous VTE. Cite this article: Bone Joint J 2017;99-B:1420–30

We compared thromboembolic events, major haemorrhage and death after total hip replacement in patients receiving either aspirin or low-molecular-weight heparin (LMWH). We analysed data from the National Joint Registry for England and Wales linked to an administrative database of hospital admissions in the English National Health Service. A total of 108 584 patients operated on between April 2003 and September 2008 were included and followed up for 90 days. Multivariable risk modelling and propensity score matching were used to estimate odds ratios (OR) adjusted for baseline risk factors. An OR <  1 indicates that rates are lower with LMWH than with aspirin. In all, 21.1% of patients were prescribed aspirin and 78.9% LMWH. Without adjustment, we found no statistically significant differences. The rate of pulmonary embolism was 0.68% in both groups and 90-day mortality was 0.65% with aspirin and 0.61% with LMWH (OR 0.93; 95% CI 0.77 to 1.11). With risk adjustment, the difference in mortality increased (OR 0.84; 95% CI 0.69 to 1.01). With propensity score matching the mortality difference increased even further to 0.65% with aspirin and 0.51% with LMWH (OR 0.77; 95% CI 0.61 to 0.98). These results should be considered when the conflicting recommendations of existing guidelines for thromboprophylaxis after hip replacement are being addressed

We compared thromboembolic events, major haemorrhage and death after knee replacement in patients receiving either aspirin or low-molecular-weight heparin (LMWH). Data from the National Joint Registry for England and Wales were linked to an administrative database of hospital admissions in the English National Health Service. A total of 156 798 patients between April 2003 and September 2008 were included and followed for 90 days. Multivariable risk modelling was used to estimate odds ratios adjusted for baseline risk factors (AOR). An AOR < 1 indicates that risk rates are lower with LMWH than with aspirin. In all, 36 159 patients (23.1%) were prescribed aspirin and 120 639 patients (76.9%) were prescribed LMWH. We found no statistically significant differences between the aspirin and LMWH groups in the rate of pulmonary embolism (0.49% vs 0.45%, AOR 0.88 (95% confidence interval (CI) 0.74 to 1.05); p = 0.16), 90-day mortality (0.39% vs 0.45%, AOR 1.13 (95% CI 0.94 to 1.37); p = 0.19) or major haemorrhage (0.37% vs 0.39%, AOR 1.01 (95% CI 0.83 to 1.22); p = 0.94). There was a significantly greater likelihood of needing to return to theatre in the aspirin group (0.26% vs 0.19%, AOR 0.73 (95% CI 0.58 to 0.94); p = 0.01). Between patients receiving LMWH or aspirin there was only a small difference in the risk of pulmonary embolism, 90-day mortality and major haemorrhage. These results should be considered when the existing guidelines for thromboprophylaxis after knee replacement are reviewed

Aims. The aim of this study was to present data on 11 459 patients who underwent total hip (THA), total knee (TKA) or unicompartmental knee arthroplasty (UKA) between November 2002 and April 2014 with aspirin as the primary agent for pharmacological thromboprophylaxis. . Patients and Methods. We analysed the incidence of deep vein thrombosis (DVT) and pulmonary embolism (PE) then compared the 90-day all-cause mortality with the corresponding data in the National Joint Registry for England and Wales (NJR). . Results. The incidence of PE was 0.6% after THA, 1.47% after TKA and 1.2% after UKA. The 90-day mortality was 0.39% after THA and 0.44% after TKA. No deaths occurred after UKA. The main causes of death were ischaemic heart disease and respiratory failure. PE was responsible for only 18% of deaths. There was a decline in 90-day mortality, from 0.64% between 2002 and 2007, to 0.21% between 2008 and 2013 after THA, and from 0.47% to 0.39% after TKA for the corresponding period. The standardised mortality ratio (SMR) declined from 86.5 (confidence interval (CI) 63.0 to 137.7) to 39.7 (CI 31.2 to 54.3) p = 0.024. The incidence of proximal DVT was 0.3%. . Take home message: With individualised risk assessment and as part of a multimodal approach, Aspirin is safe to use as the main thromboprophylactic agent in primary arthroplasty. It is not associated with an increased incidence of symptomatic DVT, PE or death. . Cite this article: Bone Joint J 2016;98-B:341-8

The incidence of deep-vein thrombosis (DVT) and pulmonary embolism (PE) is thought to be low following foot and ankle surgery, but the routine use of chemoprophylaxis remains controversial. This retrospective study assessed the incidence of symptomatic venous thromboembolic (VTE) complications following a consecutive series of 2654 patients undergoing elective foot and ankle surgery. A total of 1078 patients received 75 mg aspirin as routine thromboprophylaxis between 2003 and 2006 and 1576 patients received no form of chemical thromboprophylaxis between 2007 and 2010. The overall incidence of VTE was 0.42% (DVT, 0.27%; PE, 0.15%) with 27 patients lost to follow-up. If these were included to create a worst case scenario, the overall VTE rate was 1.43%. There was no apparent protective effect against VTE by using aspirin. We conclude that the incidence of VTE following foot and ankle surgery is very low and routine use of chemoprophylaxis does not appear necessary for patients who are not in the high risk group for VTE

Venous thromboembolism (VTE) is a preventable cause of morbidity and mortality in patients undergoing elective hip arthroplasty surgery. The balance of post-operative VTE prophylaxis and risk of post-operative haemorrhage remains at the forefront of surgeon's mind. The National Institute for Clinical Excellence (NICE) has altered their prophylaxis guidance in the setting of total hip arthroplasty (THA). The aim of this study was to present the VTE incidence in 8,890 patients who underwent total hip arthroplasty between January 1997 and March 2018 with Aspirin as the primary agent for pharmacological thromboprophylaxis. Analysis of prospective data collection from consecutive patients undergoing THA was performed with the incidence of deep vein thrombosis (DVT) and pulmonary embolism (PE) occurring within 6 months of the index operation as the primary outcome measure. 90-day all-cause mortality of this cohort of patients was also analysed. 8890 patients were reviewed. This included 7235 primary, 224 complex primary and 1431 revision cases. The incidence of DVT was 0.64% after elective THA and the incidence of PE was 0.54%. There was no difference in the incidence between primary and revision cases. The 90-day all-cause mortality was 0.88%. Cardiovascular and respiratory disease were the main causes of death following surgery. Only 0.03% of deaths (n= 3) within 90 days of index surgery were due to VTE. Our results support the use of aspirin as an effective form of prophylaxis against VTE following THA. It is not associated with an increased incidence in symptomatic DVT, PE or death compared to other published studies. The fact that it is inexpensive, readily available, requires no monitoring and does not pose an increased risk of bleeding are other attractive advantages of using aspirin for VTE prophylaxis

Aims. We investigated the efficacy and safety profile of commonly used venous thromboembolism (VTE) prophylaxis agents following hip and knee arthroplasty. Methods. A systematic search of PubMed, Embase, Cochrane Library, Web of Science, and OrthoSearch was performed. Prophylaxis agents investigated were aspirin (< 325 mg and ≥ 325 mg daily), enoxaparin, dalteparin, fondaparinux, unfractionated heparin, warfarin, rivaroxaban, apixaban, and dabigatran. The primary efficacy outcome of interest was the risk of VTE, whereas the primary safety outcomes of interest were the risk of major bleeding events (MBE) and wound complications (WC). VTE was defined as the confirmed diagnosis of any deep vein thrombosis and/or pulmonary embolism. Network meta-analysis combining direct and indirect evidence was performed. Cluster rank analysis using the surface under cumulative ranking (SUCRA) was applied to compare each intervention group, weighing safety and efficacy outcomes. Results. Of 86 studies eligible studies, cluster rank analysis showed that aspirin < 325 mg daily (SUCRA-VTE 89.3%; SUCRA-MBE 75.3%; SUCRA-WC 71.1%), enoxaparin (SUCRA-VTE 55.7%; SUCRA-MBE 49.8%; SUCRA-WC 45.2%), and dabigatran (SUCRA-VTE 44.9%; SUCRA-MBE 52.0%; SUCRA-WC 41.9%) have an overall satisfactory efficacy and safety profile. Conclusion. We recommend the use of either aspirin < 325 mg daily, enoxaparin, or dabigatran for VTE prophylaxis following hip and knee arthroplasty. Cite this article: Bone Joint J 2024;106-B(9):924–934

Purpose: The objective of this study was to examine the relationship between aspirin and other non-steroidal anti-inflammatory drugs (NSAIDS) on postoperative blood loss following Total Knee Arthroplasty. Methods: We prospectively examined the pre-operative consumption of aspirin and NSAIDS and haematological parameters of 50 consecutive patients undergoing Total Knee Arthroplasty. 22 (44%) patients were on aspirin only, 17 (34%) patients on aspirin and another NSAID and 11 (22%) patients were taking neither aspirin nor a NSAID. (All patients received 150mg of aspirin the evening before surgery as DVT prophylaxis). Results: The average pre-operative haemoglobin of the group taking aspirin and a NSAID, aspirin only and neither aspirin nor NSAID group was 12.9g/dl, 13,8g/dl and 13.49g/dl respectively. The drop between their pre-operative level and Day 3 Haemoglobin level was 3.788g/dl, 4.45g/dl and 4.28g/dl respectively. The same trend was reflected in the PCV drops of 0.111, 0.133 and 0.1273 respectively. Transfusion rates for the three groups showed that those on aspirin and another NSAID had the highest rate with an average of 0.235 units per patient compared to 0.136 for those on aspirin only and 0.10 for those on neither aspirin nor NSAID. Discussion: These findings indicate that the ingestion of aspirin or a NSAID preoperatively does not increase the amount of blood loss following total knee arthroplasty (TKA). The higher transfusion rates in the aspirin and NSAID group is because of the lower preoperative haemoglobin as compared to the other groups studied. Conclusion: Observation of transfusion trends within our unit has shown a transfusion rate of 18% in patients with a preoperative Haemoglobin level of greater than 13.0g/dl as compared to 48% with a haemoglobin level of 13.0g/dl or less (review of 180 consecutive patients undergoing Total Knee Arthroplasty). The ingestion of aspirin and NSAID does not increase blood loss following TKA but significantly have a lower preoperative Hb level. We feel that pre-operative Haemoglobin levels are the best predictors of transfusion requirements following total knee arthroplasty

Background. Few studies have compared aspirin with DOACs (direct oral anticoagulants = direct thrombin inhibitors and factor Xa inhibitors) for venous thromboembolism (VTE) prophylaxis following total hip and knee replacement (THR and TKR). We assessed the efficacy and safety of aspirin compared with DOACs for VTE prophylaxis following THR and TKR using the world's largest joint replacement registry. Methods. We studied the National Joint Registry linked to English hospital inpatient episodes for 218,650 THR and TKR patients. Patients receiving aspirin were matched separately to (1) direct thrombin inhibitors, and (2) factor Xa inhibitors using propensity scores. Outcomes assessed at 90 days included VTE, length of stay, and adverse events. Results. Following THR, the risk of VTE was significantly lower in patients receiving direct thrombin inhibitors (0.44%; odds ratio (OR)=0.69, 95% confidence interval (CI)=0.55–0.87, p=0.002) and factor Xa inhibitors (0.37%; OR=0.63, CI=0.47–0.85, p=0.003) compared with aspirin (0.63%). Following THR, direct thrombin inhibitors (coefficient=−0.37, CI=−0.43 to −0.31, p<0.001) and factor Xa inhibitors (coefficient=−0.80, CI=−0.87 to −0.74, p<0.001) reduced length of stay compared with aspirin. Similar findings for both outcomes were observed following TKR. Compared with aspirin, DOACs did not increase the risk of short-term revision surgery; reoperation; major haemorrhage; wound disruption; surgical site infection; and mortality. Conclusions. Following THR and TKR, the risk of VTE was lower in patients receiving DOACs compared with aspirin. DOACs were associated with a reduced length of stay, and DOACs did not increase the risk of further surgery, wound problems, bleeding complications, or mortality compared with aspirin

The October 2023 Knee Roundup. 360. looks at: Cementless total knee arthroplasty is associated with more revisions within a year; Kinematically and mechanically aligned total knee arthroplasties: long-term follow-up; Aspirin thromboprophylaxis following primary total knee arthroplasty is associated with a lower rate of early periprosthetic joint infection compared with other agents; The impact of a revision arthroplasty network on patient outcomes; Re-revision knee arthroplasty in a tertiary centre: how does infection impact on outcomes?; Does the knee joint have its own microbiome?; Revision knee surgery provision in Scotland; Aspirin is a safe and effective thromboembolic prophylaxis after total knee arthroplasty: a systematic review and meta-analysis; Patellar resurfacing and kneeling ability after total knee arthroplasty: a systematic review

Aims. Thromboprophylaxis following Total Hip Replacement (THR) surgery remains controversial, balancing VTE prevention against wound leakage and subsequent deep infection. We analysed the 90 day cause of death post THR in our institution after the implementation of new thromboprophylactic policy of low dose aspirin for low risk patients, as part of a multimodal regime. Those at high risk were anticoagulated. Patients and methods. The PAS database was used to identify patients undergoing primary THR between January 2012 and June 2017 at The Royal Derby Hospital, and all deaths within 90 days. Trauma cases were excluded. Case note review and Coroner's verdict were utilised to ascertain cause of death. Results were compared to a previous study at the same institution prior to the introduction of the new policy, where thromboprophylaxis was decided upon by surgeon preference for either LMWH, aspirin or warfarin. Results. During this period 4021 THRs were performed. The rate of mortality was 0.22% at 90 days. This compares to 0.58% in the previous study with the only other factor changing being the rapidity of post op mobilization. Of the 9 deaths, only one was due to fatal pulmonary embolism. None of the deaths were at high risk of VTE. This compared to 5 fatal pulmonary embolism deaths in1838 patients in the previous study in the LMWH group. The leading causes of death were heart failure and lower respiratory tract infection. Conclusion. Our institution reports a similar 90 day (0.22%) mortality using aspirin to that in the last 5 years on the NJR (0.3%) in which over 80% use LMWH. We confirm that fatal PE following elective THR with a multi-modal prophylaxis regime is rare. Changing to low dose aspirin in low risk patients is a safe option

Venous thromboembolism (VTE) is a serious complication after total hip and knee arthroplasty. There is still no consensus regarding the best mode of thromboprophylaxis after lower limb arthroplasty. The aim of this study was to ascertain the efficacy, safety profile and rate of adverse thromboembolic events of aspirin as extended out of hospital pharmacological anticoagulation for elective primary total hip and knee arthroplasty patients and whether these rates were comparable with published data for low molecular weight heparin (LMWH). Data was extracted from a prospective hospital acquired thromboembolism (HAT) database. The period of study was from 1st Jan 2013-31st Dec 2016 and a total of 6078 patients were treated with aspirin as extended thromboprophylaxis after primary total hip and knee arthroplasty. The primary outcome measure of deep vein thrombosis and pulmonary embolism within 90 days postoperatively was 1.11%. The secondary outcome rates of wound infection, bleeding complications, readmission rate and mortality were comparable to published results after LMWH use. The results of this study clearly show that Aspirin, as part of a multimodal thromboprophylactic regime, is an effective and safe regime in preventing VTE with respect to risk of DVT or PE when compared to LMWH. It is a cheaper alternative to LMWH and has associated potential cost savings

Introduction. Patients undergoing total knee arthroplasty (TKA) are at high risk of post operative venous thromboembolism (VTE). Edoxaban, the oral direct and selective factor Xa inhibitor, is available for preventing VTE after TKA. Recently, patients often take antiplatelet drugs including aspirin for their past illness. In our hospital, patients, in general, undergoing TKA receive edoxaban, but patients with aspirin for past illness receive only aspirin for preventing VTE. The aim of this study was to compare edoxaban and aspirin for preventing VTE in patients undergoing TKA. Materials and methods. From April 2012 to March 2014, 137 patients underwent primary TKA under general anesthesia with epidural anesthesia or femoral/ sciatic nerve block. Patients were excluded following; (1) renal dysfunction, (2) have taken anticoagulants such as warfarin for past illness. Finally, a total of 120 patients were enrolled. At the surgery, tourniquet was inflated and mid-vastus approach was used. After prosthesis implantation, tourniquet was deflated and drain tube was inserted. Intra and after operation, an intermittent pneumatic compression device was used. At postoperative day 2, edoxaban or aspirin started after removal of epidural anesthesia or drainage tube. Ninety-seven patients were assigned to receive edoxaban once daily (group E), and the rest of 23 received aspirin again same as before (group A). Edoxaban were scheduled to continue for 10 days. DVT diagnosis. At postoperative day 7, compression and colored Doppler imaging was taken for bilateral common femoral veins, superficial veins, popliteal veins and calf veins by skilled clinical technologist. Augmentation by calf squeezing and by dropped lower leg down were included. Diagnosing DVT criteria was loss of vein compressibility, presence of intraluminal echogenicity and absence of venous flow. D-dimer levels. At preoperative, postoperative days 7 and 14, plasma D-dimer levels were measured. Statistical analysis. Data were compared using independent t-test or the chi-square test. A significant difference was set at p<0.05. Results. Patients’ characteristics were shown in table 1. Age in the group A was significantly higher than in the group E. The total incidence of DVT was 40%. The incidence of DVT was significantly decreased in group E compared to group A at day 7 (group E: 34% versus group A: 65%, p<0.01) (table 2). The D-dimer level in group E was significantly decreased at postoperative day 7 (13.2 ± 6.8 (mean ± SD) vs 17.0 ± 9.1, p<0.05). At day 14, there were no significant differences (Figure 1). Discussion. In this study, edoxaban decreased the incidence of DVT after TKA compared to aspirin. The result of D-dimer supported the efficacy of edoxaban. Results showed that edoxaban is effective for preventing DVT following TKA. Recently, TKA patients often take antiplatelet drugs including aspirin for their past illness. It is still controversial to add an antithrombotic drug for preventing VTE. The incidence of DVT with aspirin was higher than that with edoxaban. Thus, patients received only aspirin might be needed not only to pay attention to VTE, but also to add anticoagulants as edoxaban for preventing VTE

The National Institute for Health and Clinical Excellence (NICE) has thus far relied on historical data and predominantly industry-sponsored trials to provide evidence for venous thromboembolic (VTE) prophylaxis in joint replacement patients. We argue that the NICE guidelines may be reliant on assumptions that are in need of revision. Following the publication of large scale, independent observational studies showing little difference between low-molecular-weight heparins and aspirin, and recent changes to the guidance provided by other international bodies, should NICE reconsider their recommendations?. Cite this article: Bone Joint Res 2014;3:146–9

Thromboembolic disease is associated with a high degree of morbidity and mortality. There is increasing pressure for elective orthopaedic patients, including those undergoing foot and ankle surgery, to be prescribed chemical thromboprophylaxis post-operatively in order to reduce the risk of a thromboembolic event. The risks of chemical thromboprophylaxis in terms of increased bleeding, wound problems and HIT are well documented. The aim of this study was to determine the incidence of clinically significant thromboembolic events in patients undergoing elective foot and ankle surgery with and without the use of aspirin. We audited a consecutive series of 1625 patients undergoing elective foot and ankle surgery between 2003 and 2010. Between 2003 and 2006 inclusive, aspirin was used post operatively as chemical thromboprohylaxsis. Between 2007 and 2010, no chemical thromboprohylaxsis was used. The follow-up period for all patients was at least three months post-operatively. Most patients were reviewed at 3 months by the senior surgeon. Those who were reviewed less than 3 months (patients undergoing minor procedures) were contacted via telephone to confirm whether a thromboembolic event had been diagnosed. There was no loss to follow up. Of the 1625 patients, 555 patients received aspirin and 1070 patients received no chemical thromboprohylaxsis. 5 of 1625 (0.31%) patients developed a clinically significant thromboembolic event. 3 patients developed a DVT at an average time of 5 weeks post operatively. 2 patients developed non-fatal PE at an average time of 7 weeks post operatively. 3 of the 5 thromboembolic events occurred in the aspirin group (all DVT's) whereas 2 of the 5 (all PE) developed in the non aspirin group. The incidence of clinically significant thromboembolic events is low in elective orthopaedic foot and ankle surgery. We suggest that the benefit of chemical thromboprophylaxis does not outweigh its potential risks in foot and ankle surgery

Introduction: The recent BOA blue book on blood conservation in elective orthopaedic surgery highlighted the need for blood saving strategies to be implemented. Perioperative management guidelines of oral anti-coagulation and anti-thrombosis medication have to date concentrated on warfarin use. Information and guidelines on aspirin usage in elective orthopaedics and its effects post operatively are limited. Methods: Data was collected prospectively from 1936 patients who underwent 2024 primary unilateral total hip replacement in a single institution. All patients were treated with the same postoperative transfusion regime and thromboembolic prophylaxis. Preoperative medication, haemoglobin levels and patient demographics were recorded by a standard assessment. Post op transfusion requirements and haemoglobin levels were noted throughout the postoperative period. Results: Multivariate analysis revealed that preoperative aspirin use was a significant independent predictor of postoperative transfusion requirement (p< 0.001). Discussion: Expanding indications for the use of aspirin for primary and secondary cardiovascular disease prevention have meant that large numbers of our patients undergoing total hip replacement are concurrently taking the drug. With increasing and emerging evidence of the risks involved in blood transfusion, including vCJD transmission and immune related reactions coupled with reduced supplies of donor blood further measures to reduce transfusion requirement are needed. We recommend that in the absence of absolute contraindications to stopping aspirin therapy, it should be omitted for 1 week prior to total hip replacement

The June 2023 Trauma Roundup. 360. looks at: Aspirin or low-molecular-weight heparin for thromboprophylaxis?; Lateral plating or retrograde nailing for distal femur fractures?; Sciatic nerve palsy after acetabular fixation: what about patient position?; How reliable is the new OTA/AO classification for trochanteric hip fractures?; Young hip fractures: is a medial buttress the answer?; When is the best time to ‘flap’ an open fracture?; The mortality burden of nonoperatively managed hip fractures

Introduction: Venous thromboembolism is a major cause of morbidity and mortality in hospitalised patients and patients undergoing major orthopaedic surgery are at high risk from venous thromboembolism. Thromboprophylaxis, both mechanical and chemical, is commonly administrated to reduce fatality from thromboembolism after surgery. However, there is no convincing evidence in the literature demonstrating that routine chemothromboprophylaxis reduces death rates from pulmonary embolus. Furthermore, it is unclear from the literature which thromboprophylactic agent, if any, should be used. Recent NICE guidelines have recommended that heparin should be routinely administered to patients under-going THR to prevent thromboembolism, although it is unclear from the existing evidence if heparin is the most effective. However, research has suggested that aspirin, which is a low cost prophylactic agent, is effective in preventing DVT and PE after orthopaedic surgery. The aim of this study was to determine the 90-day mortality rate after THR using aspirin as a prophylactic agent. Patients and Methods: Between 2003–2006, 2,286 patients underwent primary THR and 372 patients underwent revision hip replacement (RHR). Routine chemothromboprophylaxis consisting of aspirin 75mg daily for 6 weeks. In addition all patients were treated with anti-thromboembolic stockings. 40mg of subcutaneous clexane, in lieu of aspirin, was given daily to all patients who had previously suffered from a pulmonary embolus or deep venous thrombosis. Patients who died within 90 days of surgery had their death certificates examined. Retrieval at 90 days with regard to death was 100%. Results:. Primary THR. One patient (0.04%) died within 30 days of surgery and a further 3 (0.13%) died between day 30 and day 90, giving a total mortality at 90 days of 0.17% (4/2,286). One patient (0.04%) died from PE and the other 3 patients (0.13%) died from non-vascular causes. Revision hip replacement. One patient (0.27%) died within 30 days of surgery and a further 1 patient (0.27%) died between day 30 and day 90, giving a total mortality at 90 days of 0.54% (2/367). Both patients died from non-vascular causes. Discussion: This study found that the 30-day mortality rate for primary THR and RHR was 0.08% and the 90-day mortality rate was 0.23%. In this study, there was only one death from PE and no deaths from arterial complications. Therefore, although NICE guidelines suggest the use of heparin, this study found that routine aspirin administration is beneficial in protecting against early death after THR because of both thromboembolism and adverse arterial events

The August 2024 Knee Roundup. 360. looks at: Calcification’s role in knee osteoarthritis: implications for surgical decision-making; Lower complication rates and shorter lengths of hospital stay with technology-assisted total knee arthroplasty; Revision surgery: the hidden burden on surgeons; Are preoperative weight loss interventions worthwhile?; Total knee arthroplasty with or without prior bariatric surgery: a systematic review and meta-analysis; Aspirin triumphs in knee arthroplasty: a decade of evidence; Efficacy of DAIR in unicompartmental knee arthroplasty: a glimpse from Oxford

Background: Percutaneous compression plating (PCCP) is used for the fixation of intertrochanteric hip fractures by a minimally invasive technique. While offering several advantages compared to classic open reduction and internal fixation, the technique does not allow direct hemostasis. We aimed to assess the effect of regular aspirin use on blood loss, transfusion requirements and wound complications in patients undergoing urgent fixation using this technique. Methods: The study involved 326 patients who presented to our hospital with an intertrochanteric fracture. Parameters recorded included time to surgery, blood loss (assessed by pre and post operative hemoglobin concentrations), and transfusion requirements. The status of wound healing was evaluated, with specific reference to hematoma formation. The influence of regular pre-operative aspirin use was analyzed with respect to these outcome measures. Results: 32% of patients were regular aspirin users, and were comparable to the non aspirin group. There was no significant difference between the aspirin and non aspirin groups in terms of preoperative hemoglobin concentrations, perioperative changes in hemoglobin levels, and transfusion requirements. The severity of wound hematoma and the number of drainage procedures was not significantly different between the two groups. In a multivariate logistic regression analysis (composite complications. *. versus no complications as the dependent variable. R. 2. =0.108, P< 0.001), only delay to surgery was associated with a higher complication rate. *. Composite complications defined as transfusion ≥3 units, abnormal wound hematoma and length of stay ≥ 10 days. Conclusion: Regular aspirin use pre-operatively is not associated with increased blood loss, transfusion requirements and wound complications in patients treated with this percutaneous fixation technique. Rather, it is the delay to surgery that is associated with a composite bad outcome. Our data suggest that patients on aspirin can safely undergo urgent non-delayed fracture fixation using the PCCP

The Pulmonary Embolism Prevention (PEP) Trial was designed to assess the effects of a 35 day course of aspirin (160 mg daily) on the risks of thromboembolic events, other cardiovascular outcomes and bleeding among individuals undergoing surgery for hip fracture or joint replacement. From 1992 to 1998, 148 hospitals in Australia, New Zealand, South Africa, Sweden and the United Kingdom randomised 13,356 hip fracture patients, and 22 hospitals in New Zealand randomised 4,088 elective arthroplasty patients. Among hip fracture patients, aspirin produced proportional reductions in PE of 43% (95% confidence interval [CI] 18% to 60%; 2P=0.002) and symptomatic DVT of 29% (95% CI 3% to 48%; 2P=0.03). PE or DVT was confirmed in 105 (1.6%) of 6679 patients allocated aspirin versus 165 (2.5%) of 6677 allocated placebo, representing an absolute reduction of 9±2 per 1000 and a proportional reduction of 36% (95% CI 19% to 50%; 2P=0.0003). Aspirin prevented 4±1 fatal pulmonary emboli per 1000 treated (18 aspirin vs 43 placebo deaths), representing a proportional reduction of 58% (95% CI 27% to 76%; 2P=0.002), with no apparent effect on deaths from other vascular (hazard ratio 1.04; 95% CI 0.86 to 1.26) or non-vascular cause (1.01; 95% CI 0.84 to 1.23). Deaths due to bleeding were rare (13 aspirin vs 15 placebo), but there was an excess of 6±3 post-operative transfused bleeds per 1000 allocated aspirin (2P=0.04). Among elective arthroplasty patients, venous thromboembolism rates were lower but the proportional effects of aspirin appeared similar to those among hip fracture patients

Background. The most appropriate form of chemical thromboprophylaxis following knee replacement is a contentious issue. Most national guidelines recommend the use of low molecular weight Heparin (LMWH) whilst opposing the use of aspirin. We compared thromboembolic events, major haemorrhage and death after knee replacement in patients receiving either aspirin or LMWH. Methods. Data from the National Joint Registry for England and Wales was linked to an administrative database of hospital admissions in the English National Health Service. A total of 156 798 patients undergoing knee replacement between April 2003 and September 2008 were included and followed up for 90 days. Multivariable risk modelling was used to estimate odds ratios adjusted for baseline risk factors (AOR). An AOR < 1 indicates that risk rates are lower with LMWH than with aspirin. Results. In all, 23.1% of patients were prescribed aspirin and 76.9% LMWH. We found no statistically significant differences in the rate of pulmonary embolism (aspirin 0.49%, LMWH 0.45%, AOR 0.88; 95% confidence intervals (CI) 0.74 to 1.05), 90-day mortality (0.39% versus 0.45%, AOR 1.13; 95% CI 0.94–1.37) and major haemorrhage (0.37% versus 0.39%, AOR 1.01; 95% CI 0.83–1.22). There was a significantly greater likelihood of requirement for return to theatre in the aspirin group (0.26% versus 0.19%, AOR 0.73; 95% CI 0.58–0.94). Discussion. Between patients receiving LMWH or aspirin, there was no difference in the risk of pulmonary embolus, 90-day mortality and major haemorrhage. These results should be considered when the existing guidelines for thromboprophylaxis after knee replacement are reviewed

Aims. The aims of this study were to compare the efficacy of two agents, aspirin and warfarin, for the prevention of venous thromboembolism (VTE) after simultaneous bilateral total knee arthroplasty (SBTKA), and to elucidate the risk of VTE conferred by this procedure compared with unilateral TKA (UTKA). Patients and Methods. A retrospective, multi-institutional study was conducted on 18 951 patients, 3685 who underwent SBTKA and 15 266 who underwent UTKA, using aspirin or warfarin as VTE prophylaxis. Each patient was assigned an individualised baseline VTE risk score based on a system using the Nationwide Inpatient Sample. Symptomatic VTE, including pulmonary embolism (PE) and deep vein thrombosis (DVT), were identified in the first 90 days post-operatively. Statistical analyses were performed with logistic regression accounting for baseline VTE risk. Results. The adjusted incidence of PE following SBTKA was 1.0% (95% confidence interval (CI) 0.86 to 1.2) with aspirin and 2.2% (95% CI 2.0 to 2.4) with warfarin. Similarly, the adjusted incidence of VTE following SBTKA was 1.6% (95% CI 1.1 to 2.3) with aspirin and 2.5% (95% CI 1.9 to 3.3) with warfarin. The risk of PE and VTE were reduced by 66% (odds ratio (OR) 0.44, 95% CI 0.25 to 0.78) and 38% (OR 0.62, 95% CI 0.38 to 1.0), respectively, using aspirin. In addition, the risk of PE was 204% higher for patients undergoing SBTKA relative to those undergoing UTKA. For each ten-point increase in baseline VTE risk, the risk of PE increased by 25.5% for patients undergoing SBTKA compared with 10.5% for those undergoing UTKA. Patients with a history of myocardial infarction or peripheral vascular disease had the greatest increase in risk from undergoing SBTKA instead of UTKA. Conclusion. Aspirin is more effective than warfarin for the prevention of VTE following SBTKA, and serves as the more appropriate agent for VTE prophylaxis for patients in all risk categories. Furthermore, patients undergoing SBTKA are at a substantially increased risk of VTE, even more so for those with significant underlying risk factors. Patients should be informed about the risks associated with undergoing SBTKA. Cite this article: Bone Joint J 2018;100-B(1 Supple A):68–75

In a randomised trial we compared the effects of two different antithrombotic regimens on the incidence of venographically established deep venous thrombosis (DVT) in 83 patients undergoing surgery for fracture of the femoral neck. Group A received dextran 40 peroperatively plus 0.5 g aspirin a day beginning before operation and continuing for 10 days after. Group B received heparin calcium 5000 iu subcutaneously plus dihydroergotamine (DHE) 0.5 mg intramuscularly, given 8-hourly, beginning before operation and continuing for 10 days after. Two patients in Group A and three in Group B developed proximal DVT, while the incidence of all DVT was 33% in Group A and 29% in Group B, a difference which was not significant. Haemorrhagic complications were much more common in the dextran/aspirin group: the volume of drainage fluid, the number of patients transfused and quantity of blood transfused, and the drop in haemoglobin level were all significantly greater in Group A. We conclude that the DHE/heparin regime is preferable to dextran/aspirin because it is safer and no less effective

Aims. The place of thromboprophylaxis in arthroplasty surgery remains controversial, with a challenging requirement to balance prevention of potentially fatal venous thrombo-embolism with minimising wound-related complications leading to deep infection. We compared the incidence of fatal pulmonary embolism in patients undergoing elective primary total hip arthroplasty (THA) between those receiving aspirin, warfarin and low molecular weight heparin (LMWH) for the chemical component of a multi-modal thromboprophylaxis regime. Patients and Methods. A prospective audit database was used to identify patients who had died within 42 and 90 days of surgery respectively between April 2000 and December 2012. A case note review was performed to ascertain the causes of death. Results. During this period 7983 THAs were performed. The rate of mortality was 0.43% and 0.58% at 42 and 90 days respectively. The groups comprised 1571 patients (19.7%) on warfarin, 1838 (23.0%) on LMWH and 4574 (57.3%) on aspirin. The 90-day mortality for these three groups was 0.38%, 1.09% and 0.43% respectively. The higher mortality rate for LMWH was significant (p < 0.05). There were six fatal pulmonary emboli (PEs) (0.08%). A total of three occurred within 42 days, all in the LMWH group. A total of three occurred between 42 and 90 days; one on warfarin, two on LMWH. The leading causes of death in all three groups were lower respiratory tract infections and myocardial infarction. Conclusion. We confirmed that fatal PE following elective THA with a multi-modal prophylaxis regime is rare. We further found that LMWH conferred no benefit over aspirin in this context, and is associated with a higher all-cause rate of mortality. Take home message: This study proposes that aspirin may be an appropriate thromboprophylaxis agent when used as part of a multi-modal regimen, suggesting current guidelines should be reviewed. Cite this article: Bone Joint J 2016;98-B:585–8

Current orthopedic practice requires consideration of apparently contradictory recommendations regarding VTE prevention among THR/TKR patients. American College of Chest Physicians (ACCP) 8th Clinical Practice Guidelines for the Prevention of Venous Thromboembolism recommend against aspirin for VTE prophylaxis in any patient. 1. The American Academy of Orthopedic Surgeons (AAOS) Guideline recommends pulmonary embolism risk stratification, then implementation of one of many possible courses including the use of aspirin. 2. . We conducted a prospective observational study among consecutive patients presenting for total hip or knee arthroplasty. Pre-operative PE risk stratification was performed at the discretion of the surgeon. Patients identified as usual risk for PE received aspirin. Patients considered being at elevated risk for PE received warfarin. This observational study protocol called for one year of data collection. At approximately 8 months 656 patients were enrolled, and the surgeon principally implementing PE risk stratification and administration of aspirin chose to stop enrolling patients due to a high incidence of pulmonary emboli. One hundred fifty five patients received thromboprophylaxis with aspirin 600 mg PR in the PACU, then 325 mg BID for one month (reduced to 81 mg daily if GI symptoms were present). The remaining 501 patients received an ACCP-based warfarin protocol managed by a pharmacist anticoagulation management service. Our hypothesis is the null hypothesis; that an AAOS-based approach to hromboembolism prevention is not inferior to an ACCP-based approach. The a priori primary endpoints of the AVP Study are clinically overt VTE, DVT, PE, major bleeding, and death. All patients will receive a 90 day follow-up questionnaire in person or by telephone. Additionally, the electronic medical record of Intermountain Healthcare will be interrogated for ICD-9 codes germane to the outcomes of interest. Ninety day follow-up has been completed for approximately 140 patients. The dataset will be locked upon completion of the 90 day follow-up among those patients who last received PE risk stratification and aspirin therapy (data lock early June, 2009). We anticipate preliminary data available for report by July, 2009

Following the outcomes of the RECORD trials the protocol of extended thromboprophylaxis in patients undergoing elective primary total hip or knee arthroplasty has been changed in our institution. Between June 2008 and May 2009 patients were offered extended thromboprophylaxis with 150mg of aspirin daily, commencing preoperatively on admission and continuing for a total of six weeks. From June 2009 onwards patients were treated with 10mg of rivaroxaban once daily for two weeks following total knee and five weeks following total hip arthroplasty commencing 4 to 6 hours postoperatively. Our cohorts were 700 patients before and after the introduction of the new regimen. The two groups were matched for age, sex and type of operation. All patients with no contraindication to treatment with aspirin or rivaroxaban respectively undergoing elective primary total hip or knee arthroplasty were included in the study. Patients receiving warfarin on admission were treated with warfarin postoperatively and were excluded. We have compared the two treatment protocols in terms of safety and efficacy. Results focus on 4 safety outcome measures including mortality, haemorrhagic complications, transfusion requirements and infection rates and 2 efficacy outcome measures including thromboembolic complications and length of inpatient stay. Rates of DVT were equal in the two cohorts (P< 0.005) as were the mortality rates. Transfusion requirements post-operatively were not affected by the introduction of the new regimen however there was a significant increase in both return to theatre rates and prolonged wound ooze (P< 0.005). Infection rates were slightly higher in the cohort treated with rivaroxaban but this was not statistically significant. We conclude that further trials need to be done to confirm the suitability of routine use of rivaroxiban

Upper gastrointestinal (GI) bleeding in patients who undergo hip and knee arthroplasty tends to be associated with NSAID use, steroid intake, pre-existing peptic ulcers and smoking. The use of Aspirin for thromboprophylaxis is an added risk for the occurrence of GI Bleed. The aim of this study was to determine if the use of peri-operative oral Ranitidine reduces the incidence of GI bleeding when Aspirin thromboprophylaxis is used for hip and knee arthroplasty. Data from 1491 consecutive patients who underwent Hip and knee replacements at the James cook university hospital (Group 1) and 886 patients who underwent Hip and Knee replacements at the Friarage hospital, Northallerton (Group 2) was analysed to determine the incidence of Gastro intestinal Bleeding. All patients received 150 mg of Aspirin per day for a period of six weeks from the day of surgery. Additionally patients operated at the Friarage Hospital received 300 mg of oral Ranitidine per day, for three postoperative days. Patients with clinically symptomatic GI bleeding were evaluated by the Upper GI team. We observed that patients in Group 1 had a higher incidence of overt upper GI haemorrhage (n=14), which was statistically significant (p < 0.014) compared with patients in group 2(n=1). From the pooled data of both groups, there were 18 reported patients with symptomatic pulmonary embolism (0.75%) 3 of which were fatal (0.12%), phlebitis of deep leg veins in 31 patients (1.3%), deep vein thrombosis in 34 patients (1.43%), 5 of whom had embolic episodes, post operative infection in 22 patients (1.13%), and postoperative haemorrhage in 5 patients (0.2%). Thromboembolic phenomenon and pulmonary embolism was confirmed by autopsy in the three cases. Based on this experience, we recommend the use of peri-operative gastric protection when aspirin is used for thromboprophylaxis in hip and knee arthroplasty

Introduction. Venous thromboembolism (VTE), defined as either pulmonary embolism (PE) or deep venous thrombosis (DVT), is a rare, but serious complication following total hip arthroplasty (THA). Current VTE guidelines recommend pharmacologic agents with or without intermittent pneumatic compression devices (IPCDs). At our institution, both 81mg aspirin (ASA) twice a day (BID) and portable IPCDs were prescribed to THA patients at standard risk for VTE. The aim of this study is to determine if discontinuing the use of portable outpatient IPCDs is safe and does not increase the rate of VTE in patients undergoing THA. Methods. A retrospective review of 1,825 consecutive THA cases was conducted identifying patients with a VTE 90-days postoperatively. Patients were divided into two separate consecutive cohorts. Cohort one consisted of THA patients who received outpatient IPCDs for a period of 14 days (control). Cohort two consisted of THA patients without outpatient IPCDs (experimental). Patients were non-randomized to 81mg ASA BID for 28 days for VTE chemoprophylaxis. An interim power analysis was performed to determine the proper sample size. Results. A total of 748 patients were discharged with outpatient IPCDs while 1,077 patients were discharged without IPCDs. There were no VTE events found in control group (0%). The total VTE rate of the experimental group was 0.2% (2 PE and 1 DVT). There was no statistical difference between these rates (p=0.24). A binary logistic regression did not detect any significant associations for any VTE outcomes even after accounting for demographic differences. Conclusion. Our findings suggest that discontinued use of outpatient portable IPCDs is safe and does not increase the rate of VTE in standard risk patients undergoing THA while using 81mg ASA BID as VTE prophylaxis

Aims

The aims of this study were to determine the indications and frequency of ordering a CT pulmonary angiography (CTPA) following primary arthroplasty of the hip and knee, and to determine the number of positive scans in these patients, the location of emboli and the outcome for patients undergoing CTPA.

Dabigatran etexilate (Pradaxa^®) is an oral direct thrombin inhibitor that was recently approved in Europe and Canada for the prevention of venous thromboembolism (VTE) in patients undergoing total knee arthroplasty (TKA) or total hip arthroplasty (THA) surgery. In the phase III studies, concomitant administration of selective nonsteroidal anti-inflammatory drugs (NSAIDs with t½≤12 hours) and acetylsalicylic acid (ASA; < 160 mg/day) was allowed during treatment with dabigatran etexilate or enoxaparin. Due to the potential additional anticoagulant activity of these concomitant therapies a separate post hoc analysis was conducted to investigate the bleeding risk in these patients. We analysed the pooled study population (8,135 patients) from the three phase III trials in THA and TKA surgery (RE-MOBILIZE, RE-MODEL and RE-NOVATE) for major bleeding events (MBE). All MBE, which included surgical site bleeds, were assessed by an independent, expert adjudication committee. We report the rates of MBE and odds ratios (with 95% confidence intervals [CI]) for comparison of the subgroup concomitantly treated with NSAID (or ASA) versus the subgroup of patients without concomitant antithrombotically active medication. The overall rate of MBE (with and without NSAIDs and ASA) was 1.4% [CI 1.0–1.9], 1.1% [0.7–1.5] and 1.4% [1.0–2.0] with dabigatran etexilate 220 mg, 150 mg, and enoxaparin, respectively. Of the total population, 57.4% of patients received concomitant antithrombotic treatment: 54.1% received NSAID and 4.7% received ASA. The MBE rate in patients receiving dabigatran etexilate or enoxaparin plus NSAIDs was similar to the rate in patients taking only dabigatran etexilate or enoxaparin; 1.5% vs. 1.4% [OR 1.05; 0.55–2.01] for dabigatran etexilate 220 mg, 1.1% vs. 1.0% [OR 1.19; 0.55–2.55] for dabigatran etexilate 150 mg, and 1.6% vs. 1.2% [OR 1.32; 0.67–2.57] for enoxaparin. A similar pattern was seen in patients concomitantly receiving ASA; in this small group only a few patients with MBE were observed: 2 (1.6%) in the dabigatran etexilate 220 mg group, 2 (1.6%) in the 150 mg group, and 4 (3.0%) in the enoxaparin group. No relevant differences in risk for MBE were detected between treatments by co-medication subgroup or within treatment groups when comparing patients receiving dabigatran etexilate or enoxaparin only versus those concomitantly receiving NSAIDs or ASA. In conclusion, patients concomitantly receiving dabigatran etexilate and NSAIDs (with t½ ≤12 hours) or ASA (< 160 mg/day) have a similar risk of MBE to patients taking only dabigatran etexilate. These data support the use of dabigatran etexilate for the prevention of VTE in patients after THA or TKA, when concomitant use of NSAIDs or ASA (< 160 mg/day) is required.

Aims. It is common practice for patients to have postoperative blood tests after total joint replacement (TJR). However, there have been significant improvements in perioperative care with arthroplasty surgery, and a drive to reduce the length of stay (LOS) and move towards day-case TJR. We should reconsider whether this intervention is necessary for all patients. Methods. This retrospective study included all patients who underwent a primary unilateral TJR at a single tertiary arthroplasty centre during a one-year period. Electronic medical records of 1,402 patients were reviewed for patient demographics, LOS, and American Society of Anesthesiologists (ASA) grade. Blood tests were examined to investigate the incidence of postoperative anaemia, electrolyte abnormalities, and incidence of acute kidney injury (AKI). Results. For total knee arthroplasties, preoperative (R = −0.22) and postoperative haemoglobin (R = 0.2) levels were both negatively correlated with LOS (p < 0.001). For all patients who had undergone a TJR, 19 patients (0.014%) required a blood transfusion postoperatively due to symptomatic anaemia. Risk factors identified were age, preoperative anaemia, and long-term aspirin use. Significant abnormal sodium levels were found in123 patients (8.7%). However, only 36 patients (2.6%) required intervening treatment. Risk factors identified were age, preoperative abnormal sodium level, and long-term use of non-steroidal anti-inflammatory drugs, angiotensin receptor blockers, and corticosteroids. Similarly, abnormal potassium levels were evident in 53 patients (3.8%), and only 18 patients (1.3%) required intervening treatment. Risk factors identified were preoperative abnormal potassium level, and long-term use of angiotensin-converting enzyme inhibitors and diuretics. The incidence of AKI was 4.4% (61 patients). Risk factors identified were age, increased ASA grade, preoperative abnormal sodium, and creatinine level. Conclusion. Routine blood tests after primary TJR is unnecessary for most patients. Blood tests should only be performed on those with identifiable risk factors such as preoperative anaemia and electrolyte abnormalities, haematological conditions, long-term aspirin use, and electrolyte-altering medications. Cite this article: Bone Jt Open 2023;4(5):357–362

Considerable debate exists regarding which agent(s) should be preferred for venous thromboembolism (VTE) chemical prophylaxis following joint replacement. We assessed the practice of surgeons regarding VTE chemical prophylaxis for primary THR and TKR, pre and post issuing of updated NICE guidance in 2018. A survey, circulated through the British Hip Society and regional trainee networks/collaboratives, was completed by 306 UK surgeons at 187 units. VTE chemical prophylaxis prescribing patterns for surgeons carrying out primary THR (n=258) and TKR (n=253) in low-risk patients were assessed post publication of 2018 NICE recommendations. Prescribing patterns before and after the NICE publication were subsequently explored. Questions were also asked about surgeon equipoise for participation in future RCTs. Following the new guidance, 34% (n=87) used low-molecular weight heparin (LMWH) alone, 33% (n=85) aspirin (commonly preceded by LMWH), and 31% (n=81) direct oral anticoagulants (DOACs: with/without preceding LMWH) for THR. For TKR, 42% (n=105) used aspirin (usually monotherapy), 31% (n=78) LMWH alone, and 27% (n=68) DOAC (with/without preceding LMWH). NICE guidance changed the practice of 34% of hip and 41% of knee surgeons, with significantly increased use of aspirin preceded by LMWH for THR (before=25% vs. after=73%;p<0.001), and aspirin for TKR (before=18% vs. after=84%;p<0.001). Significantly more regimens were NICE guidance compliant after the 2018 update for THR (before=85.7% vs. after=92.6%;p=0.011) and TKR (before=87.0% vs. after=98.8%;p<0.001). Support from surgeons for future RCTs was dependent on the clinical question, ranging from 48% participation in trials (effectiveness of aspirin vs. a DOAC) to 79% (effectiveness of 14 days LMWH vs. 28 days LMWH). Over one-third of surveyed surgeons changed their VTE chemical prophylaxis in response to 2018 NICE recommendations, with more THR and TKR surgeons now compliant with latest NICE guidance. The major change in practice was an increased use of aspirin for VTE chemical prophylaxis. Furthermore, there is an appetite amongst UK surgeons for participating in future RCTs, with a trial comparing standard versus extended duration LMWH likely feasible in current practice

Aims. We studied the safety and efficacy of multimodal thromboprophylaxis in patients with a history of venous thromboembolism (VTE) who undergo total hip arthroplasty (THA) within the first 120 postoperative days, and the mortality during the first year. Multimodal prophylaxis includes discontinuation of procoagulant medications, VTE risk stratification, regional anaesthesia, an intravenous bolus of unfractionated heparin prior to femoral preparation, rapid mobilization, the use of pneumatic compression devices, and chemoprophylaxis tailored to the patient’s risk of VTE. Methods. Between 2004 to 2018, 257 patients with a proven history of VTE underwent 277 primary elective THA procedures by two surgeons at a single institution. The patients had a history of deep vein thrombosis (DVT) (186, 67%), pulmonary embolism (PE) (43, 15.5%), or both (48, 17.5%). Chemoprophylaxis included aspirin (38 patients), anticoagulation (215 patients), or a combination of aspirin and anticoagulation (24 patients). A total of 50 patients (18%) had a vena cava filter in situ at the time of surgery. Patients were followed for 120 days to record complications, and for one year to record mortality. Results. Postoperative VTE was diagnosed in seven patients (2.5%): DVT in five, and PE with and without DVT in one patient each. After hospitalization, three patients required readmiss-ion for evacuation of a haematoma, one for wound drainage, and one for monitoring of an elevated international normalized ratio (INR). Seven patients died (2.5%). One patient died five months postoperatively of a PE during open thrombectomy. She had discontinued anticoagulation. One patient died of a haemorrhagic stroke while receiving Coumadin. PE or bleeding was not suspected in the remaining five fatalities. Conclusion. Multimodal prophylaxis is safe and effective in patients with a history of VTE. Postoperative anticoagulation should be prudent as very few patients developed VTE (2.5%) or died of suspected or confirmed PE. Mortality during the first year was mostly unrelated to either VTE or bleeding. Cite this article: Bone Joint J 2020;102-B(7 Supple B):71–77

Thromboprophylaxis after elective orthopaedic surgery remains controversial. Recent guidelines from the National Institute for Clinical Excellence (NICE) have suggested that low molecular weight heparin should be given to all patients undergoing total hip replacement. The British Orthopaedic Association is currently debating this guideline with NICE, as it is not clear whether published evidence supports this view. We present the early mortality in our unit after total hip replacement using aspirin as chemical thromboprophylaxis. The 30-day and 90-day mortality after primary total hip arthroplasty was zero. We compare this with that reported previously from our unit without using chemical thromboprophylaxis. With the introduction of routine aspirin thromboprophylaxis, deaths from cardiovascular causes have dropped from 0.75% to zero. These results demonstrate that there is a strong argument for the routine administration of aspirin after elective total hip replacement

Patients who sustain hip fractures should be operated on within 24 hours of admission according to the Royal College Of Physician Guidelines. A delay to theatre of more than 4 days is associated with an increase in inpatient mortality. A high proportion of patients with hip fractures are elderly and take aspirin, clopidogrel or warfarin. A retrospective review of 100 patients admitted between December 2006 and July 2007 with a hip fracture was conducted. Our aims were to assess the proportion of patients taking antithrombotic medication, when the antithrombotic medication was stopped pre-operatively and see whether there was a delay to theatre. We also evaluated any association between patients taking antithrombotic medication and a return to theatre, post-operative morbidity and mortality and length of inpatient stay. 47 patients were taking aspirin, 1 was taking clopidogrel, 2 were on aspirin and clopidogrel and 3 patients were taking warfarin. The aspirin group had an increased delay to theatre compared to the no antithrombotic group, however, both groups had similar numbers operated on within 24 hours. 68% (32/47) patients had the aspirin stopped on the same day as the operation. 1 patient taking aspirin returned to theatre for evacuation of a haematoma. The main post-operative complication was pneumonia (n=9). 8 patients required a blood transfusion of which 5 were taking aspirin. The main causes of mortality were ischaemic heart disease (n=7) and pneumonia (n=5). The mean lengths of inpatient stay were 22.48 days in the aspirin group, 50 days in the aspirin and clopidogrel group, 66 days in the clopidogrel group, 24.33 in the warfarin group and 24.81 days in the no antithrombotic group. It is suggested from this small study that there is no advantage in stopping aspirin prior to hip fracture surgery. However, further studies need to be undertaken

We studied 4253 patients undergoing primary joint replacement between November 2002 and November 2007, of whom 4060 received aspirin only as chemical prophylaxis; 46 were mistakenly given low molecular weight heparin initially, which was stopped and changed to aspirin; 136 received no chemoprophylaxis and 11 patients received warfarin because of a previous history of pulmonary embolism. We identified the rate of clinical thromboembolism before and after discharge, and the mortality from pulmonary embolism at 90 days. The overall death rate was 0.31% (13 of 4253) and the rate of fatal pulmonary embolism was 0.07% (3 of 4253). Our data suggest that fatal pulmonary embolism is not common following elective primary joint replacement, and with modern surgical practice elective hip and knee replacement should no longer be considered high-risk procedures

Background: Aetiology of venous thromboembolism is multifactorial and thromboprophylaxis includes mechanical and chemical agents. There is no clear consensus on the choice of chemical agent in elective total hip arthroplasty (THA), although National Institute of Clinical Excellence (NICE) recommends low molecular weight heparin or fondaparinux to all patients. Aim: The aim of our study was to define the efficacy and safety of various chemical agents currently used for venous throboprophylaxis – namely aspirin, warfarin and low molecular weight heparin in primary THA. Methods: We retrospectively reviewed 905 consecutive patients with primary THA during an 18 month period. Medical notes were reviewed to record demographic data, inpatient and outpatient thromboprophylactic agents, total hospital stay, readmission, incidence of DVT, pulmonary embolism and death following surgery. Post-operative mobility, transfusion requirements and complications were noted. Suspected thromboembolic events were investigated with venous Doppler ultrasound scanning and CTPA. Results: 417 (46%) patients received aspirin, 253 received enoxaparin, 190 patients had low dose warfarin and 45 patients had none or multiple agents for inpatient thromboprophylaxis. 615 patients had cemented and 290 patients received uncemented total hip arthroplasty. Patients predominantly received aspirin (61%) as outpatient prophylactic agent. 41 patients were investigated for a suspected thromboembolic event. 2 patients had DVT and 2 patients had PE. There were 3 deaths within 6 weeks, one each due to PE, sepsis and unknown cause. All 4 patients with thromboembolism were on enoxaparin for prophylaxis. Conclusion: In our study aspirin was the preferred choice for thromboprophylaxis following total hip arthroplasty. We found that aspirin was most effective with no complications and enoxaparin was least effective. We advise the use of aspirin as the first choice drug for thromboprophylaxis as reiterated by some recent studies

Thromboprophylaxis is of particular interest to the NHS due to the number of deaths from preventable hospital-acquired venous thrombo-embolism, considerable treatment cost and related long-term morbidities. In compliance with current NICE guidelines, our departmental protocol for chemical thromboprophylaxis changed from aspirin to clexane. We present a review of the use of both these chemical agents in our hip fracture patients; assessing duration of wound ooze, incidence of symptomatic PE and DVT and thrombocytopaenia. Prospective study of surgically treated hip fractures patients on chemical thromboprophylaxis postoperatively over a 7 month period. Of 224 patients reviewed, 110 fitted our inclusion criteria; 78 on Clexane and 32 on aspirin. Mean patient age: 82.6 years(48–100). Mean hospital stay: 30d ays(6–80). Female predominance (3:1). Mean duration of wound ooze: 6.9 days (1–24) for aspirin and 5.6 days (0–15) for clexane. Symptomatic DVTs: 1(3%) for aspirin and 3(3.8%) for clexane. Symptomatic PE: 0 for aspirin and 1(1.3%) for clexane. Thrombocytopenia: 0 for both groups. Mean duration of wound ooze for both groups was approximately 1 week. Low but significant incidence of thrombo-embolism. Thromboembolism-deterrent-stockings were observed to be unreliable mainly due to skin problems and compliance

Objective: To examine the impact of aspirin and non-steroidal anti-inflammatory drugs (NSAIDs) on preoperative haemoglobin levels and perioperative transfusion rates in patients undergoing total knee arthroplasty (TKA). Methods: We examined the pre-operative haemoglobin (Hb) and haematocrit (Hct) of a consecutive series of 81 patients, looking at the relationship between the pre-operative use of Aspirin/NSAIDs on preoperative Hb, postoperative Hb deficit and the perioperative transfusion rate. A single surgeon performed all procedures using an LCS TKR (Depuy, Leeds UK). A standardised transfusion protocol was used. Results: The patients were grouped according to their pre-operative use of aspirin or a NSAID, singly or in combination. The patient groups are as shown in the table below. All groups were comparable for age, BMI and ASA grade. Results show a significantly higher transfusion rate (p=0.048) in the group of patients who received a combination of aspirin and a NSAID compared to the other groups. The patients on aspirin or a NSAID alone also had an increased transfusion rate but the increase was not statistically significant (p=0.12 and p=0.07 respectively). Conclusion: The use of both aspirin and an NSAID in combination leads to a lower preoperative Hb and an increased post-operative transfusion requirement following total knee arthroplasty

Immobilisation is known to be a risk factor for thromboembolic events and the management of ankle fractures often involves immobilisation of the fracture in a below knee cast. Recent literature has found a 5% rate of subclinical deep vein thrombosis (DVT) and suggested thromboembolic prophylaxis is not required. This study involved all adult patients with isolated ankle fractures presenting to a district general hospital orthopaedic department over a 6 month period. This included patients undergoing internal fixation as well as non-operative management. A 3 to 7 month follow-up was performed to assess the incidence of clinical DVT or pulmonary embolism (PE) proven using Doppler imaging, venogram, and computed tomography pulmonary angiography. 119 patients met the entry criteria and, of these, 3 patients developed DVT and 2 patients presented with pulmonary embolus. 15 patients in the study were taking aspirin (75–300 mg daily) during their cast immobilisation and 1 patient was taking warfarin. None of these patients developed a thromboembolic complication. 4.8% of patients not taking aspirin or warfarin experienced a thromboembolic complication. This study demonstrates a relatively high incidence of symptomatic thromboembolism following ankle fractures in the absence of prophylaxis. Previous studies have found aspirin to be an effective method of prophylaxis following hip fractures and total hip arthroplasty. We recommend that thromboembolism prophylaxis is necessary following ankle fractures and suggest that aspirin may be an economical option. Larger studies are needed to evaluate the role of aspirin in this setting

Background. Hip fracture in the elderly has high morbidity and mortality. National guidelines have recommended low molecular weight (LMW) heparin or aspirin for thromboprophylaxis in hip fracture. Unlike other types of major surgery, there is a lack of trial evidence for graduated elasticated compression (GEC) stockings in hip fracture patients. Objective. To explore the effect of thromboprophylaxis on survival in hip fracture patients. Participants. 8470 Scottish Hip Fracture Audit (SHFA) participants aged 60 years and over, admitted 1998-2003. Methods. SHFA records were linked to routinely collected hospital discharge and death records occurring within one year of hip fracture admission. Cox proportional hazards regression was used to adjust for age, gender, previous hospital admissions, previous walking ability and residence, American Society of Anesthesiologists grade, fracture type, pressure sores prior to surgery, and delay to surgery. Results. 2531 (30%) patients died within one year of hip fracture admission. GEC stockings appeared to be protective against death (hazard ratio 0.88, 95% confidence interval 0.80-0.97) as did aspirin (HR 0.85, 95% CI 0.76-0.95). However heparin did not appear to protect against death (HR 0.97, 95% CI 0.87-1.08), even when only LMW heparin was included in the analysis. Overall, 3318 (39%) patients were given GEC stockings, 2735 (32%) aspirin, and 4527 (53%) heparin. Patients commonly received more than one type of thromboprophylaxis. Conclusions. This study provides evidence for a protective effect of GEC stockings and aspirin following hip fracture, but not heparin. The study design allowed sophisticated analysis, adjusting for a number of functional, social, surgical, anaesthetic and medical factors. The findings may however be explained by other confounding factors not included in the analysis. These findings suggest that a randomised controlled trial of GEC stockings, aspirin and heparin in hip fracture patients is warranted

Aim:. This prospective cohort study investigated whether the use of preoperative anticoagulants is an independent risk factor for the outcomes of surgical treatment of patients with a neck of femur fracture. Methods:. Data was obtained from a prospectively collected database. All patients admitted for a neck of femur fracture between Nov 2010 and Oct 2011 were included. This resulted in three hundred twenty-eight patients with 330 neck of femur fractures. Four groups were defined; patients preoperatively (i) on aspirin (n = 105); (ii) on clopidogrel (n = 28); (iii) on warfarin (n = 30); and (iv) without any anticoagulation history (n = 167, the control group). The non-warfarin group included the aspirin group, clopidogrel group and the control group. Primary outcome was the in-hospital mortality. Secondary outcomes were the postoperative complications, return to theatre and length of stay. Results:. Thirteen in-hospital deaths were identified, 4 deaths in the aspirin group, 1 death in the clopidogrel group, 2 deaths in the warfarin group and 6 deaths in the control group. No significant difference in the mortality rates was found between the different groups. Also in the secondary outcomes, no significant difference was found between the four groups. A trend to a higher wound complication rate for the warfarin group was detected. Conclusion:. The use of clopidrogel or aspirin pre operatively is not an influence on short term patient outcome for patients with a neck of femur fracture. Surgical procedures should not be delayed to reverse their influence

Aims. We studied the impact of direct anterior (DA) versus non-anterior (NA) surgical approaches on prosthetic joint infection (PJI), and examined the impact of new perioperative protocols on PJI rates following all surgical approaches at a single institution. Patients and Methods. A total of 6086 consecutive patients undergoing primary total hip arthroplasty (THA) at a single institution between 2013 and 2016 were retrospectively evaluated. Data obtained from electronic patient medical records included age, sex, body mass index (BMI), medical comorbidities, surgical approach, and presence of deep PJI. There were 3053 male patients (50.1%) and 3033 female patients (49.9%). The mean age and BMI of the entire cohort was 62.7 years (18 to 102, . sd. 12.3) and 28.8 kg/m. 2. (13.3 to 57.6, . sd. 6.1), respectively. Infection rates were calculated yearly for the DA and NA approach groups. Covariates were assessed and used in multivariate analysis to calculate adjusted odds ratios (ORs) for risk of development of PJI with DA compared with NA approaches. In order to determine the effect of adopting a set of infection prevention protocols on PJI, we calculated ORs for PJI comparing patients undergoing THA for two distinct time periods: 2013 to 2014 and 2015 to 2016. These periods corresponded to before and after we implemented a set of perioperative infection protocols. Results. There were 1985 patients in the DA group and 4101 patients in the NA group. The overall rate of PJI at our institution during the study period was 0.82% (50/6086) and decreased from 0.96% (12/1245) in 2013 to 0.53% (10/1870) in 2016. There were 24 deep PJIs in the DA group (1.22%) and 26 deep PJIs in the NA group (0.63%; p = 0.023). After multivariate analysis, the DA approach was 2.2 times more likely to result in PJI than the NA approach (OR 2.2 (95% confidence interval 1.1 to 3.9); p = 0.006) for the overall study period. Conclusion. We found a higher rate of PJI in DA versus NA approaches. Infection prevention protocols such as use of aspirin, dilute povidone-iodine lavage, vancomycin powder, and Gram-negative coverage may have been positively associated with diminished PJI rates observed for all approaches over time. Cite this article: Bone Joint J 2019;101-B(6 Supple B):2–8

We performed a meta-analysis of the English literature to assess the efficacy of four common regimes for thromboembolic prophylaxis after total knee arthroplasty: aspirin, warfarin, low-molecular-weight heparin (LMWH) and pneumatic compression. We reviewed 136 articles and abstracts published between January 1980 and December 1997. Papers not using routine venography and a lung scan or angiography to detect deep-venous thrombosis (DVT) and pulmonary emboli (PE) respectively, were excluded. Of the 136 studies, 23 with 6001 patients were selected. The incidence of DVT was 53% (1701/3214) in the aspirin group, 45% (541/1203) in the warfarin group, 29% (311/1075) in the LMWH group, and 17% (86/509) in the pneumatic compression device group. Intermittent pneumatic compression devices and LMWH were significantly better than warfarin (p < 0.0001) or aspirin (p < 0.0001) in preventing DVT. The incidence of asymptomatic PE was 11.7% in the aspirin group (222/1901), 8.2% (101/1229) in the warfarin group and 6.3% (24/378) in the pneumatic compression group. No studies with LMWH used routine lung scans. Warfarin and pneumatic compression were significantly better than aspirin in preventing asymptomatic PE (p < 0.05). The incidence of symptomatic PE was 1.3% (23/1800) in the aspirin group, 0.4% (2/559) in the warfarin group, 0.5% (2/416) in the LMWH group and 0% (0/177) in the pneumatic compression group. No statistically significant difference was noted between the above prophylatic regimes due to the very small incidence of symptomatic PE. Prophylaxis for thromboembolic disease in TKA may have to include a combination of some of the above regimes to incorporate their advantages