The incidence of fatal pulmonary embolism after primary hip and knee replacement in a consecutive series of 4253 patients

Implementing NICE guidelines on risk assessment for venous thromboembolism: failure, success and controversy

PURPOSE

Venous thromboembolism (VTE) prophylaxis guidelines were originally published by the National Institute of Clinical Excellence (NICE) in April 2007. Controversy eclipsed their release. Consequently, the VTE prophylaxis publication was reviewed and republished in January 2010. The NICE guidelines recommend that all patients are assessed for risk before pharmacological prophylaxis is offered and reassessed at 24 hours to check adverse reactions; and that prophylaxis is appropriate. This paper aims to look at their implementation.

DESIGN/METHODOLOGY/APPROACH

A prospective audit and re-audit in one orthopaedic department was completed to see how well the new guidelines were adhered to, find out first-hand what problems there were, and how they might be remedied.

FINDINGS

Audit and re-audit highlighted that attaching an assessment tool to drug charts is plausible.

RESEARCH LIMITATIONS/IMPLICATIONS

The study was limited to one centre and used a relatively weak research design.

PRACTICAL IMPLICATIONS

As a process, the clinical impact of risk assessment for VTE is questionable as many patients will be high risk. Removing reassessment at 24 hours from the NICE guidance is recommended.

ORIGINALITY/VALUE

The authors put the NICE guideline into clinical practice, demonstrating how effectively it can work with their method, but also highlighting its flaws.

Socioeconomic burden of total joint arthroplasty for symptomatic hip and knee osteoarthritis in the Italian population: a 5-year analysis based on hospitalization records

OBJECTIVE

To assess the burden of total joint arthroplasties (TJAs) performed for symptomatic hip and knee osteoarthritis (OA) in the Italian population.

METHODS

We analyzed national hospitalizations and diagnosis-related group databases to compute incidence, annual percent change (APC), direct costs, and working days lost between 2001 and 2005 following TJA due to OA.

RESULTS

In 2005, we recorded a total of 41,816 (APC +5.4; 95% confidence interval [95% CI] 5.1-5.8) and 44,051 (APC +13.4; 95% CI 13.1-13.8) hip and knee arthroplasties, respectively. Women represented the majority of patients undergoing TJA procedures (female:male ratio 1.7:1 for hip arthroplasties and 2.9:1 for knee arthroplasties). When analyzing the data by age groups, most of the patients were in the age groups 65-74 years and ≥75 years, although the highest increases were observed in those ages <65 years. Revisions accounted for 6,387 (APC +4.9; 95% CI 4.0-5.7) and 2,295 (APC +17.4; 95% CI 15.7-19.2) procedures for the hip and knee, respectively. Loss of working days in patients ages <65 years was estimated between 805,000 and 1 million days. Hospital costs increased from 741 million to 1 billion euros over the 5-year period (from 412 to 538 million euros for hip arthroplasties and from 329 to 517 million euros for knee arthroplasties). Rehabilitation costs increased from 228 to 322 million euros. Postoperative complications were estimated between 3.1 and 4.4 million euros. The average costs per patient were 16,835 and 15,358 euros for hip and knee arthroplasties, respectively.

CONCLUSION

The socioeconomic burden of TJAs performed for symptomatic OA in Italy is remarkable and calls for the adoption of proper preventive measures.

Fast-track hip and knee arthroplasty: clinical and organizational aspects

Fast-track hip and knee arthroplasty aims at giving the patients the best available treatment at all times, being a dynamic entity. Fast-track combines evidence-based, clinical features with organizational optimization including a revision of traditions resulting in a streamlined pathway from admission till discharge – and beyond. The goal is to reduce morbidity, mortality and functional convalescence with an earlier achievement of functional milestones including functional discharge criteria with subsequent reduced length of stay and high patient satisfaction. Outcomes are traditionally measured as length of stay; safety aspects in the form of morbidity/mortality; patient satisfaction; and – as a secondary parameter – economic savings. Optimization of the clinical aspects include focusing on analgesia; DVT-prophylaxis; mobilization; care principles including functional discharge criteria; patient-characteristics to predict outcome; and traditions which may be barriers in optimizing outcomes. Patients should be informed and motivated to be active participants and their expectations should be modulated in order to improve satisfaction. Also, organizational aspects need to be analyzed and optimized. New logistical approaches should be implemented; the ward ideally (re)structured to only admit arthroplasties; the staff educated to have a uniform approach; extensive preoperative information given including discharge criteria and intended length of stay. This thesis includes 9 papers on clinical and organizational aspects of fast-track hip and knee arthroplasty (I–IX). A detailed description of the fast-track set-up and its components is provided. Major results include identification of patient characteristics to predict length of stay and satisfaction with different aspects of the hospital stay (I); how to optimize analgesia by using a compression bandage in total knee arthroplasty (II); the clinical and organizational set-up facilitating or acting as barriers for early discharge (III); safety aspects following fast-track in the form of few readmissions in general (IV) and few thromboembolic complications in particular (V); feasibility studies showing excellent outcomes following fast-track bilateral simultaneous total knee arthroplasty (VI) and non-septic revision knee arthroplasty (VII); how acute pain relief in total hip arthroplasty is not enhanced by the use of local infiltration analgesia when multi-modal opioid-sparing analgesia is given (VIII); and a detailed description of which clinical and organizational factors detain patients in hospital following fast-track hip and knee arthroplasty (IX). Economic savings following fast-track hip and knee arthroplasty is also documented in studies, reviews, metaanalyses and Cochrane reviews – including the present fast-track (ANORAK). In conclusion, the published results (I–IX) provide substantial, important new knowledge on clinical and organizational aspects of fast-track hip and knee arthroplasty – with concomitant documented high degrees of safety (morbidity/mortality) and patient satisfaction. Future research strategies are multiple and include both research strategies as efforts to implement the fast-track methodology on a wider basis. Research areas include improvements in pain treatment, blood saving strategies, fluid plans, reduction of complications, avoidance of tourniquet and concomitant blood loss, improved early functional recovery and muscle strengthening. Also, improvements in information and motivation of the patients, preoperative identification of patients needing special attention and detailed economic studies of fast- track are warranted.

Long-term patient-reported outcomes after total hip replacement: comparison to the general population

Hip replacement is one of the most common elective procedures performed in the NHS, with patients generally reporting good mid-term outcomes. However, patient-reported long-term outcomes have been less well studied. The aim of this study was to explore the extent of variation in long-term patient reported outcomes after total hip replacement (THR), and to compare outcomes to a control population without THR. All patients who had undergone primary THR at one centre 12-16 years ago and who had previously completed an Oxford hip score (OHS) 5-8 years post-operatively were invited to complete a postal OHS. Participants in the control group who had not undergone hip or knee replacement also completed an OHS. The Oxford hip score (OHS) was completed by 407 THR patients and 927 controls. The median score of 18 for the THR patients was significantly worse than the median score of 12 for the control group (p <0.001). Similar results were found when comparisons were stratified by age. There was considerable variation in change in OHS from 5-8 years to 12-16 years post-operatively, although a significant worsening in outcome was found only in patients over 80 years old. Patients continue to report good functional outcomes at 12-16 years after THR, although function is signficantly worse than the general population who have not undergone THR.

Mortality and morbidity following hip fractures related to hospital thromboprophylaxis policy

Chemical thromboprophylaxis has been shown to reduce the incidence of venous thromboembolism (VTE) for patients with fractures of the hip, but it is not known with certainty whether it use also reduces mortality. Using postal and telephone questionnaires we collected data from English National Health Service (NHS) hospitals about their thromboprophylaxis policy for hip fractures patients from April 2003 to April 2007. Using Hospital Episode Statistics (HES) we ascertained in-hospital mortality rates at 30 days and at one year following admission to hospital. Unplanned hospital readmission rates for all causes (including episodes of thromboembolism and bleeding) within 30 days (all years) and one year (2003 to 2005) were also established. A total of 150 hospitals were contacted and data gathered from 62 hospitals (response rate 41.3%) There were 255841 patients with neck of femur fractures during this five year period who were assessed for morbidity and mortality, and we correlat these with thromboprophylaxis policy. There was no significant difference in hospital readmission within 30 days, or diagnosis of thromboembolism or haemorrhage among hospitals with different thromboprophylaxis policies. The hospitals using low molecular weight heparin (LMWH) in half the dose recommended by the British National Formulary had significantly reduced mortality in-hospital (odds ratio (OR) 0.79, 95% CI 0.69-0.90, P=0.0006), at 30 days (OR 0.8 (0.70 - 0.92), P=0.001) and at one year (OR 0.89 (0.80 - 1.00), P=0.050), compared with those with no such policy. Our data suggest that the thromboprophylaxis regimen for patients with fracture neck of femur should be half dose LMWH for the duration of the hospital stay.

Direct thrombin inhibitor (DTI) vs. aspirin in primary total hip and knee replacement using wound ooze as the primary outcome measure. A prospective cohort study

The latest NICE guidance dictates that all patients undergoing lower-limb arthroplasty should be prescribed potent venous thromboembolic (VTE) prophylaxis. However, use of potent anti-thrombotics is likely to lead to increased post-operative wound ooze. Postoperative wound ooze is associated with increased risk of infection. This study used a prospective, consecutive, multi-surgeon sample of 110 patients undergoing primary total hip replacement (THR) and total knee replacement (TKR) prescribed either direct thrombin inhibitor (DTI) (n=51, 26 males: 25 females, age 69 ±18) or aspirin (n=59, 25 males: 34 females, age 69 ± 19). Hospital stay, body mass index (BMI), wound length and patient demographics were documented along with a daily assessment of wound ooze. The use of DTI's was associated with a significant increase in mean days to dryness in both THR (6.2 ± 0.98, 95% C.I. 5.2-7.1) and TKR (6.6 ± 1.89, 95% C.I. 4.7-8.5) compared to aspirin in THR (3.0 ± 1.03, 95% C.I 1.9-4.0) and TKR (3.4 ± 1.21, 95% C.I 2.2-4.6) with p-values of <0.0001 and 0.0024 for THR and TKR respectively. Age, gender and wound length were not found to be significant confounding variables. DTI's proven benefit in lowering venous thromboembolism when compared with aspirin needs to be balanced with their increased cost and increased duration of wound ooze.

Venous thromboembolism and its prophylaxis in elective total hip arthroplasty: an international perspective

INTRODUCTION

Patients undergoing total hip arthroplasty (THA) are at high risk of developing post-operative deep vein thrombosis (DVT) or a subsequent pulmonary embolus (PE). Despite best efforts, the best prophylaxis for thromboembolic disease remains controversial. This article aims to update the reader on the newest guidelines concerning venous thromboembolism (VTE) prophylaxis for elective THAs, considering their advantages and disadvantages and highlighting their inconsistencies.

METHODS

The Medline database and the Internet were searched for VTE prophylaxis guidelines in English. Nine guidelines were found and compared. The comparison looked at the recommendations made, the grade of recommendation, the level of evidence available for these recommendations and any inconsistencies between the guidelines.

RESULTS

All guidelines advocate the use of LMWH and almost all advocate the use of mechanical methods of prophylaxis. The recommended duration ranges from 7-35 days and in many cases, the duration is not specified. There is little consensus in terms of other recommended drugs, the doses, duration and their recommendation grades.

CONCLUSION

There is still uncertainty about the optimal methods of thromboprophylaxis in elective total hip arthroplasty. Although there are always going to be disagreements about the endpoints amongst guideline makers, guidelines should achieve uniformity in their criteria for levels of evidence and recommendation grades, facilitating the clinician's decision-making process.

Wound problems following hip arthroplasty before and after the introduction of a direct thrombin inhibitor for thromboprophylaxis

In the United Kingdom, national guidelines have stated that patients undergoing elective hip surgery are at increased risk for venous thromboembolic events (VTE) following surgery and have recommended thromboprophylaxis for 28-35 days (1, 2). Studies of direct thrombin inhibitors have hitherto concentrated on major bleeding. We prospectively assessed wound discharge in patients who underwent hip arthroplasty and who received oral dabigatran postoperatively between March 2010 and April 2010 (n=56). We compared these results to a retrospective matched group of patients who underwent similar operations six months earlier, at which time all patients were given subcutaneous dalteparin routinely postoperatively until discharge, and then discharged home on 150 mg aspirin daily for 6 weeks (n=67). Wound discharge after 5 days was significantly higher in the patients taking dabigatran (32% dabigatran n=18, 10% dalteparin n=17, p=0.003) and our rate of delayed discharges due to wound discharge significantly increased from 7% in the dalteparin group (n=5) to 27% for dabigatran (n=15, p=0.004). Patients who received dabigatran were more than five times as likely to return to theatre with a wound complication compared with those who received dalteparin (7% dabigatran n=4, vs. 1% dalteparin n=1), but this was not statistically significant (p=0.18). We now administer dalteparin until the wound is dry and then start dabigatran. Our study demonstrates the need for further clinical studies regarding wound discharge and direct thrombin inhibitors.

Elective hip and knee arthroplasty and the effect of rivaroxaban and enoxaparin thromboprophylaxis on wound healing

INTRODUCTION

Rivaroxaban is the first licensed oral direct inhibitor of factor Xa. Recent studies from the RECORD trials suggest rivaroxaban has superior efficacy compared to enoxaparin in preventing venous thromboembolism (VTE) with no significant increase in the major bleeding risk. Concerns remain regarding the incidence of minor bleeding, consequent delayed wound healing and subsequent risk of infection. The aim of this observational study was to assess the incidence of post-operative complications in patients receiving either rivaroxaban or enoxaparin thromboprophylaxis following elective hip and knee arthroplasty.

METHODS

A total of 258 patients undergoing elective total hip or knee arthroplasty within one NHS Trust were included. A total of 202 subjects (mean age, 70.7 years ± 10.0, 43 % men) received a daily dose of 10 mg of oral rivaroxaban and 56 (mean age, 70.9 years ± 9.8, 39 % men) had a daily subcutaneous injection of 40 mg of enoxaparin as thromboprophylaxis. Endpoints included VTE (deep vein thrombosis and pulmonary embolism), haemorrhagic wound complications, hospital re-admission, requirement for blood transfusion, minor and major bleeding and death.

RESULTS

There were no significant differences in the incidence of VTE, requirement for blood transfusion and readmission rate between rivaroxaban and enoxaparin-treated patients. The incidence of minor bleeding (2.0 vs. 0 %) and haemorrhagic wound complications (5.0 vs. 1.8 %) were non-significantly higher in the rivaroxaban-treated group. There were no cases of pulmonary embolism, major bleeding or death in either group.

CONCLUSION

Our experience with rivaroxaban in elective hip and knee arthroplasty showed no significant difference in the incidence of VTE or major bleeding. There was, however, a tendency to greater risk of minor bleeding and wound complications that were largely haemorrhagic in nature, which may have reached significance in a larger study.

Meta-analysis of cause of death following total joint replacement using different thromboprophylaxis regimens

We performed a meta-analysis of modern total joint replacement (TJR) to determine the post-operative mortality and the cause of death using different thromboprophylactic regimens as follows: 1) no routine chemothromboprophylaxis (NRC); 2) Potent anticoagulation (PA) (unfractionated or low-molecular-weight heparin, ximelagatran, fondaparinux or rivaroxaban); 3) Potent anticoagulation combined (PAC) with regional anaesthesia and/or pneumatic compression devices (PCDs); 4) Warfarin (W); 5) Warfarin combined (WAC) with regional anaesthesia and/or PCD; and 6) Multimodal (MM) prophylaxis, including regional anaesthesia, PCDs and aspirin in low-risk patients. Cause of death was classified as autopsy proven, clinically certain or unknown. Deaths were grouped into cardiopulmonary excluding pulmonary embolism (PE), PE, bleeding-related, gastrointestinal, central nervous system, and others (miscellaneous). Meta-analysis based on fixed effects or random effects models was used for pooling incidence data. In all, 70 studies were included (99 441 patients; 373 deaths). The mortality was lowest in the MM (0.2%) and WC (0.2%) groups. The most frequent cause of death was cardiopulmonary (47.9%), followed by PE (25.4%) and bleeding (8.9%). The proportion of deaths due to PE was not significantly affected by the thromboprophylaxis regimen (PA, 35.5%; PAC, 28%; MM, 23.2%; and NRC, 16.3%). Fatal bleeding was higher in groups relying on the use of anticoagulation (W, 33.8%; PA, 9.4%; PAC, 10.8%) but the differences were not statistically significant. Our study demonstrated that the routine use of PA does not reduce the overall mortality or the proportion of deaths due to PE.

Patient-reported history of leg ulceration 12-16 years after total primary knee or hip replacement

BACKGROUND AND PURPOSE

Deep vein thrombosis is common after total joint replacement. It is frequently asymptomatic, and it is unclear whether this leads to longer-term problems such as post-thrombotic syndrome and leg ulceration. We investigated whether the postoperative prevalence of ulceration in patients who had undergone primary total hip replacement (THR) or total knee replacement (TKR) was higher than that found in a control group who had not undergone total joint replacement.

METHODS

The study group consisted of patients who had undergone THR or TKR at one orthopedic center 12-16 years previously without routine chemothromboprophylaxis, and who had not undergone revision surgery. The control group was recruited via primary care. All participants were recruited by post and asked to complete a questionnaire. Age- and sex-adjusted prevalence of self-reported leg ulceration was calculated, and logistic regression was used to determine whether there were any associations between THR or TKR and leg ulceration.

RESULTS

Completed questionnaires were received from 441 THR patients (54% response rate), 196 TKR patients (48%) and 967 control participants (36%). No statistically significant differences in age- and sex-adjusted prevalence of ulceration were found between the groups, for either lifetime prevalence or prevalence over the previous 15 years.

INTERPRETATION

Patients who undergo THR and TKR without chemothromboprophylaxis are unlikely to be at a higher risk of long-term venous ulceration than the normal population.

Incidence of deep vein thrombosis following total hip arthroplasty: a Doppler ultrasonographic study

PURPOSE

To investigate the incidence of deep vein thrombosis (DVT) following total hip arthroplasty (THA) in Singaporean patients.

METHODS

197 patients (mean age, 60 years) underwent primary THA (n=155) or revision procedure (n=42) without receiving routine chemoprophylaxis. There were 149 Chinese, 25 Malays, 19 Indians, and 4 Eurasians. Duplex ultrasonography to detect DVT was performed on both lower limbs on postoperative day 5.

RESULTS

15 (8%) patients developed DVT, which was proximal in 6 and distal in 9. Only one patient had pulmonary embolism. The presence of DVT did not correlate to age, gender, race, presence of diabetes mellitus, history of malignancy, smoking habit, fixation type, primary versus revision type of surgery, or operating time.

CONCLUSION

The incidence of DVT following THA in Singaporean patients is low, and routine chemoprophylaxis may not be indicated.

Return to theatre following total hip and knee replacement, before and after the introduction of rivaroxaban: a retrospective cohort study

Rivaroxaban has been recommended for routine use as a thromboprophylactic agent in patients undergoing lower-limb arthroplasty. However, trials supporting its use have not fully evaluated the risks of wound complications. This study of 1048 total hip/knee replacements records the rates of return to theatre and infection before and after the change from a low molecular weight heparin (tinzaparin) to rivaroxaban as the agent of chemical thromboprophylaxis in patients undergoing lower-limb arthroplasty. During a period of 13 months, 489 consecutive patients undergoing lower-limb arthroplasty received tinzaparin and the next 559 consecutive patients received rivaroxaban as thromboprophylaxis. Nine patients in the control (tinzaparin) group (1.8%, 95% confidence interval 0.9 to 3.5) returned to theatre with wound complications within 30 days, compared with 22 patients in the rivaroxaban group (3.94%, 95% confidence interval 2.6 to 5.9). This increase was statistically significant (p = 0.046). The proportion of patients who returned to theatre and became infected remained similar (p = 0.10). Our study demonstrates the need for further randomised controlled clinical trials to be conducted to assess the safety and efficacy of rivaroxaban in clinical practice, focusing on the surgical complications as well as the potential prevention of venous thromboembolism.

Thromboprophylaxis in orthopaedic surgery: a clinical review

Venous thromboembolism (VTE), including deep vein thrombosis (DVT) and pulmonary embolism (PE), is a common cause of cardiovascular mortality and morbidity. Patients undergoing major orthopaedic surgery, including hip and knee arthroplasty, represent a group that is at particularly high risk for VTE, especially patients with risk factors (age > 60 years, cancer, prior VTE).

Low risk of thromboembolic complications after fast-track hip and knee arthroplasty

BACKGROUND AND PURPOSE

Pharmacological prophylaxis can reduce the risk of deep venous thrombosis (DVT), pulmonary embolism (PE), and death, and it is recommended 10–35 days after total hip arthroplasty (THA) and at least 10 days after total knee arthroplasty (TKA). However, early mobilization might also reduce the risk of DVT and thereby the need for prolonged prophylaxis, but this has not been considered in the previous literature. Here we report our results with short-duration pharmacological prophylaxis combined with early mobilization and reduced hospitalization.

PATIENTS AND METHODS

1,977 consecutive, unselected patients were operated with primary THA, TKA, or bilateral simultaneous TKA (BSTKA) in a well-described standardized fast-track set-up from 2004–2008. Patients received DVT prophylaxis with low-molecular-weight heparin starting 6–8 h after surgery until discharge. All re-admissions and deaths within 30 and 90 days were analyzed using the national health register, concentrating especially on clinical DVT (confirmed by ultrasound and elevated D-dimer), PE, or sudden death. Numbers were correlated to days of prophylaxis (LOS).

RESULTS

The mean LOS decreased from 7.3 days in 2004 to 3.1 days in 2008. 3 deaths (0.15%) were associated with clotting episodes and overall, 11 clinical DVTs (0.56%) and 6 PEs (0.30%) were found. The vast majority of events took place within 30 days; only 1 death and 2 DVTs occurred between 30 and 90 days. During the last 2 years (854 patients), when patients were mobilized within 4 h postoperatively and the duration of DVT prophylaxis was shortest (1–4 days), the mortality was 0% (95% CI: 0–0.5). Incident cases of DVT in TKA was 0.60% (CI: 0.2–2.2), in THA it was 0.51% (CI: 0.1–1.8), and in BSTKA it was 0% (CI: 0–2.9). Incident cases of PE in TKA was 0.30% (CI: 0.1–1.7), in THA it was 0% (CI: 0–1.0), and in BSTKA it was 0% (CI: 0–2.9).

INTERPRETATION

The risk of clinical DVT, and of fatal and non-fatal PE after THA and TKA following a fast-track set-up with early mobilization, short hospitalization, and short duration of DVT prophylaxis compares favorably with published regimens with extended prophylaxis (up to 36 days) and hospitalization up to 11 days. This calls for a reconsideration of optimal duration of chemical thromboprophylaxis.

Readmissions after fast-track hip and knee arthroplasty

INTRODUCTION

With the implementation of fast-track surgery with optimization of both logistical and clinical features, the postoperative convalescence has been reduced as functional milestones have been achieved earlier and consequently length of stay (LOS) in hospital has been reduced. However, it has been speculated that a decrease in LOS may be associated with an increase in readmissions in general, including risk of dislocation after total hip arthroplasty (THA) or manipulation after total knee arthroplasty (TKA).

MATERIALS AND METHODS

1,731 consecutive, unselected patients were operated with primary THA or TKA in a well-described standardized fast-track setup from 2004 to 2008. All readmissions and deaths within 90 days were analyzed using the national health register.

RESULTS

Mean LOS decreased from 6.3 to 3.1 days. Within 90 days, 15.6% of patients following TKA were readmitted as opposed to 10.9% after THA (p = 0.005). Three deaths (0.17%) were associated with clotting episodes. Suspicion of DVT (not found) and suspicion of infection made up half of the readmissions. Readmissions in general and for thromboembolic events, dislocations and manipulations in specific did not increase with decreasing LOS. There was no difference between readmission rates per year for either TKA or THA but there was a significantly reduced risk of dislocation found with decreasing LOS comparing each year from 2005 to 2007 with the index year of 2004 (with the longest LOS and the highest incidence of dislocation).

CONCLUSION

Fast-track TKA and THA do not increase the readmission rate. Readmissions are more frequent after TKA than THA, but dislocation after THA and manipulation after TKA do not increase as LOS is decreasing.

Unicompartmental knee arthroplasty: incidence of transfusion and symptomatic thromboembolic disease

Unicompartmental knee arthroplasty has been associated with faster recovery with less potential perioperative morbidity compared to total knee arthroplasty. This study investigates the rate of transfusion, symptomatic thromboembolic events, and length of hospital stay in 1000 consecutive, unicompartmental knee replacements performed by 2 surgeons. A rapid recovery protocol coupled with multimodal venous thromboembolism prophylaxis was used for all patients. Five patients (0.5%) received a blood transfusion for symptomatic postoperative anemia. One patient (0.1%) developed a symptomatic deep venous thrombosis within 90 days of follow-up. No patient experienced a symptomatic pulmonary embolism. Length of hospital stay averaged 1.4 days. Unicompartmental arthroplasty using less invasive surgical techniques, a rapid recovery protocol, and multimodal venous thromboembolism prevention is a safe and effective procedure associated with a low rate of morbidity.

Oral rivaroxaban for the prevention of symptomatic venous thromboembolism after elective hip and knee replacement

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The impact of national guidelines for the prophylaxis of venous thromboembolism on the complications of arthroplasty of the lower limb

The National Institute for Clinical Excellence (NICE) produces recommendations on appropriate treatment within the National Health Service (NHS) in England and Wales. The NICE guidelines on prophylaxis for venous thromboembolism in orthopaedic surgery recommend that all patients be offered a low molecular weight heparin (LMWH). The linked hospital episode statistics of 219 602 patients were examined to determine the rates of complications following lower limb arthroplasty for the 12-month periods prior to and following the publication of these guidelines. These were compared with data from the National Joint Registry (England and Wales) regarding the use of LMWH during the same periods. There was a significant increase in the reported use of LMWH (59.5% to 67.6%, p < 0.001) following the publication of the guidelines. However, the 90-day venous thromboembolism events actually increased slightly following total hip replacement (THR, 1.69% to 1.84%, p = 0.06) and remained unchanged following total knee replacement (TKR, 1.99% to 2.04%). Return to theatre in the first 30 days for infection did not show significant changes. There was an increase in the number of patients diagnosed with thrombocytopenia, which was significant following THR (0.11% to 0.16%, p = 0.04). The recommendations from NICE are based on predicted reductions in venous thromboembolism events, reducing morbidity, mortality and costs to the NHS. The early results in orthopaedic patients do not support these predictions, but do show an increase in complications.