RISKS AND BENEFITS OF PROPHYLAXIS AGAINST VENOUS THROMBOEMBOLISM IN ORTHOPAEDIC SURGERY

Incidence of venous thromboembolism in Asian patients undergoing anterior cruciate ligament reconstruction without the use of mechanical or chemical prophylaxis

Background:

Venous thromboembolism (VTE) is a clinically relevant complication of major orthopedic surgeries. The prevalence of VTE and the indications for VTE thromboprophylaxis in Asian patients undergoing arthroscopic anterior cruciate ligament (ACL) reconstruction are not clear. This study aims to evaluate the prevalence of clinically significant venous thromboembolic events (VTE) in Asian patients undergoing arthroscopic ACL reconstruction without mechanical or chemical thromboprophylaxis.

Methods:

All patients who underwent ACL reconstruction by a single surgeon from 2006 to 2018 in a single tertiary institution were reviewed. The inclusion criteria for the study included Asian patients of common ethnic groups in Singapore (Chinese, Malay, Indian) and underwent primary or revision ACL reconstruction, or ACL reconstruction combined with meniscal surgery. The exclusion criteria were patients with incomplete medical records, pre-existing anticoagulant treatment within 1 year prior to the surgery and additional procedures that altered the standard rehabilitation protocol, less than 6 months of follow-up duration. All patients received general anesthesia. The single-bundle ACL technique with autologous hamstring tendon reconstruction was performed. No chemical DVT prophylaxis was given. The patients were screened for clinically for VTE. Symptomatic patients were referred for ultrasonography.

Results:

Of the 581 patients reviewed, 3 patients had a clinical suspicion of deep vein thrombosis, but subsequent ultrasonography showed no thrombosis. Hence, the prevalence of clinically significant VTE was 0%.

Conclusion:

Given the low prevalence of clinically significant VTE, there is no need for routine mechanical or chemical thromboprophylaxis or radiologic screening in Asian patients undergoing arthroscopic ACL reconstruction.

Post-discharge complications in postoperative patients with hip fracture

Hip fractures often occur in elderly people and are a major global health challenge causing many consequences, both in health and socioeconomic costs. This review aimed to identify complications that occur in patients with postoperative hip fracture between 30 days and 60 months after discharge. This review was conducted on articles published from 2005 to 2017 obtained from the EBSCO, PubMed, ProQuest and Google Scholar databases. The literature search followed PRISMA Guidelines. Key search words included the terms: hip fracture, complication, postoperative, community, and nursing. Articles were considered eligible if discussed the complications of hip fracture with surgical treatment, occurring post hospital discharge and the patient was in the community. In this review, 23 articles were included that met the inclusion criteria. There were 16 articles that cohort studies, 3 were retrospective studies, 3 were randomized control trials and 1 article was an observational study. The time of observation varied from 30 days to the longest of 5 years. Quality assessment of the levels of evidence used the Oxford CEBM recommendations. The review results found that postoperative hip fracture patients after discharge still experienced various complications after 30 days and up to 1-3 years post-operation.

Mechanical prophylaxis, early mobilisation and risk stratification: as effective as drugs for low risk patients undergoing primary joint replacement. Results in 13,384 patients

INTRODUCTION

Current NICE Guidelines state that all patients undergoing total hip and knee arthroplasty should be given both mechanical and chemical prophylaxis. At our institution, a targeted thromboprophylaxis policy has been in place since October 1999. The aim of this study was to calculate our venous thromboembolism rates and compare these to published rates in the literature.

METHODS

All patients are pre-operatively assessed for their VTE risk. Patients are stratified into high or low risk: all patients received mechanical thromboprophylaxis and the higher risk patients now receive chemical and mechanical thromboprophylaxis post op. Patients are reviewed at 2, 6 and 52 weeks and with annual postal questionnaires and clinical and radiological review at 5 and 10yrs.

RESULTS

13,384 primary THA and TKAs were entered into the database. The overall rate of clinically apparent DVT and overall PE rates of 0.48% and 0.42% respectively. 86.16% of our patients were low risk, of these 23.3% of patients were on Aspirin/Clopidogrel with mechanical thromboprophylaxis and 76.7% of patients had mechanical prophylaxis alone. There was no statistical difference between the DVT or PE rates in the low risk groups.

CONCLUSION

Our results show that use of early mobilisation and mechanical prophylaxis within an Enhanced Recovery Programme results in comparable VTE rates to chemical prophylaxis for all, which is reflected in the literature. Our results question the need for chemical thromboprophylaxis or extended use of mechanical thromboprophylaxis in "lower risk" patients if a risk stratification policy is used in the context of modern surgical approaches.

The influence of tourniquet use and operative time on the incidence of deep vein thrombosis in total knee arthroplasty

OBJECTIVE

To evaluate the association between tourniquet and total operative time during total knee arthroplasty and the occurrence of deep vein thrombosis.

METHODS

Seventy-eight consecutive patients from our institution underwent cemented total knee arthroplasty for degenerative knee disorders. The pneumatic tourniquet time and total operative time were recorded in minutes. Four categories were established for total tourniquet time: <60, 61 to 90, 91 to 120, and >120 minutes. Three categories were defined for operative time: <120, 121 to 150, and >150 minutes. Between 7 and 12 days after surgery, the patients underwent ascending venography to evaluate the presence of distal or proximal deep vein thrombosis. We evaluated the association between the tourniquet time and total operative time and the occurrence of deep vein thrombosis after total knee arthroplasty.

RESULTS

In total, 33 cases (42.3%) were positive for deep vein thrombosis; 13 (16.7%) cases involved the proximal type. We found no statistically significant difference in tourniquet time or operative time between patients with or without deep vein thrombosis. We did observe a higher frequency of proximal deep vein thrombosis in patients who underwent surgery lasting longer than 120 minutes. The mean total operative time was also higher in patients with proximal deep vein thrombosis. The tourniquet time did not significantly differ in these patients.

CONCLUSION

We concluded that surgery lasting longer than 120 minutes increases the risk of proximal deep vein thrombosis.

Incidence of venous thromboembolism in elective foot and ankle surgery with and without aspirin prophylaxis

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.

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.

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.

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

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.

Low-molecular-weight heparin for prevention of thrombosis: inverted role

BACKGROUND

Heparin induced thrombosis (HIT) after low-molecular-weight (LMWH) administration for thrombosis prevention is a limb and life threatening condition.

METHODS

Two previously healthy individuals, with nonviable forearm amputation and knee osteoarthritis, suffered from multiple arterial thromboses (>2 sites each) after postoperative administration of LMWH.

RESULTS

Both patients suffered from thrombocytopenia on the first postoperative days (4-7) and had signs of arterial occlusions on the 9th and 10th postoperative days. The patient with the initially successful forearm replantation was finally amputated below the elbow, whereas the lower extremity of the patient with total knee arthroplasty and contralateral femoral artery occlusion was salvaged with foot fingers amputation only.

CONCLUSIONS

Early recognition of the syndrome by monitoring daily platelet counts during heparin therapy is essential. In case of postheparin (LMWH or unfractionated) platelet decrease, heparin administration should be ceased after emergency testing for heparin induced antibodies. When HIT syndrome is confirmed to have occurred, heparin/LMWH must be replaced with thrombin-specific inhibitors.

Venous thromboembolism associated with hip and knee replacement over a ten-year period

This population-based study investigated the incidence and trends in venous thromboembolic disease after total hip and knee arthroplasty over a ten-year period. Death or readmission for venous thromboembolic disease up to two years after surgery for all patients in Scotland was the primary outcome. The incidence of venous thromboembolic disease, including fatal pulmonary embolism, three months after surgery was 2.27% for primary hip arthroplasty and 1.79% for total knee arthroplasty. The incidence of fatal pulmonary embolism within three months was 0.22% for total hip arthroplasty and 0.15% for total knee arthroplasty. The majority of events occurred after hospital discharge, with no apparent trend over the period. The data support current advice that prophylaxis should be continued for at least six weeks following surgery. Despite the increased use of policies for prophylaxis and earlier mobilisation, there has been no change in the incidence of venous thromboembolic disease.

Total Joint Arthroplasties: Current Concepts of Patient Outcomes after Surgery

Total hip and knee arthroplasties are effective surgical interventions for relieving pain and improving physical function caused by arthritis. Although the majority of patients substantially improve, not all reports gains or are satisfied after receiving a total joint arthroplasty. This article reviews the literature on patient outcomes after total hip and knee arthroplasties for osteoarthritis and the evidence pertaining to factors that affect these patient-centered outcomes. Mounting evidence suggests that no one patient-related or peri-operative factor clearly predicts the amount of pain relief or functional improvement that will occur following total hip or knee arthroplasty.

Prolonged enoxaparin therapy to prevent venous thromboembolism after primary hip or knee replacement. A cost-utility analysis

BACKGROUND

Among patients undergoing elective total hip or knee replacement, prolonged prophylaxis with low-molecular-weight heparin significantly reduces the risk of symptomatic venous thromboembolism. Whether implementing routine prolonged prophylaxis is cost-effective remains uncertain.

METHODS

We performed an economic modeling study to compare the costs and health outcomes of standard (12 days) with prolonged (42 days) enoxaparin prophylaxis against venous thromboembolism after elective total hip and knee replacement. The primary economic perspective was that of a societal healthcare payer, taking Belgium as a case country. We used cost-utility analysis, a form of cost effectiveness analysis in which costs are reported in monetary terms (euros) and health outcomes are converted into quality-adjusted life years (QALYs) gained, thereby incorporating a measure of quality of life (utility) into the health outcomes. Costs for diagnosis and treatment of proximal and distal deep vein thrombosis, pulmonary embolism, postphlebitic syndrome, and major bleeding were obtained from a Delphi panel (orthopaedic surgeons) and the official reimbursement rates (Federal Ministry of Health). QALYs for these health outcomes were based on utility scores as reported in the literature. The main outcome measure was the incremental cost-utility ratio, reported as the incremental cost per quality-adjusted life year gained (euros/QALY). The incremental cost-utility ratio refers to the amount of money needed to produce one additional QALY. We also performed sensitivity analyses on clinical and economic parameters to identify important model uncertainties.

RESULTS

In the base-case analysis, incremental costs of prolonged prophylaxis amounted to 58 euros and 114 euros per patient, with an additional gain in QALY of 0.0083 and 0.0018 after total hip and knee replacement, respectively. Thus, a strategy of prolonged enoxaparin prophylaxis was associated with a cost-utility ratio of 6,964 euros/QALY and 64,907 euros/QALY after total hip and knee replacement, respectively. This tenfold difference in incremental cost-utility ratios between hip and knee replacement might have important practical implications. According to recent European guidelines, an intervention costing less than 20,000 euros per QALY is said to exhibit strong evidence for adoption, whereas one costing 20,000-100,000 euros exhibits moderate evidence for adoption. By current European guidelines, the cost of 6,964 euros and 64,907 euros per QALY gained would give strong evidence for adoption of prolonged enoxaparin prophylaxis among total hip replacement patients, but moderate evidence for adoption among total knee replacement patients. Sensitivity analyses using 20% changes from the base-case analysis showed this outcome to be robust.

CONCLUSIONS

Our findings indicate that, among patients undergoing elective total hip or knee replacement, prolonged enoxaparin prophylaxis leads to increased health benefits at increased cost. Given the additional costs that healthcare decision makers in Europe are usually prepared to pay for a gain in utility, prolonged prophylaxis with enoxaparin is cost-effective after elective total hip replacement, and our data provide strong evidence for adoption of prolonged enoxaparin prophylaxis after elective total hip replacement.

Evidence‐based guidelines for fixing broken hips: an update

OBJECTIVE

To update evidence-based guidelines for the treatment of proximal femoral fractures published in the Journal in 1999.

DATA SOURCES

Systematic literature search of MEDLINE, CINAHL and EMBASE from January 1996 to September 2001 and the Cochrane Database of Systematic Reviews (most recent issue searched - Issue 2, 2002).

STUDY SELECTION

Randomised controlled trials and meta-analyses of all aspects of acute-care hospital treatment and rehabilitation of proximal femoral fractures among subjects aged 50 years and over with proximal femoral fractures not associated with metastatic disease or multiple trauma.

DATA EXTRACTION

All studies were read independently by two reviewers. Reviewers recorded individual study results, and an assessment of study quality and treatment conclusions according to Cochrane Collaboration protocols. If necessary, a third review was performed to reach consensus.

RESULTS

93 new studies were identified and 82 met our inclusion criteria. Recommendations for thromboprophylaxis, anaesthesia, surgical fixation of fractures and nutritional status have been altered to incorporate new evidence. Recommendations have been added regarding postoperative blood transfusion, the management of subtrochanteric fractures, and the type of surgical swabs which should be used.

CONCLUSIONS

Although there have been few significant changes to the previous recommendations, updating the guidelines has required substantial effort. The common clinical problem of hip fracture should be treated according to the most up-to-date evidence to achieve the best possible outcomes and optimal utilisation of limited resources. Guideline updates also require resourcing.