Rivaroxaban for Thromboprophylaxis in Patients Undergoing Major Orthopedic Surgery

The safety and efficacy of NOACs versus LMWH for thromboprophylaxis after THA or TKA: A systemic review and meta-analysis

The differences in the safety and efficacy of anticoagulation between different types of new oral anticoagulants(NOACs) and low molecular weight heparin(LMWH) are still controversial. The main purposes of this study were to analyze safety and efficacy of NOACs versus LMWH for thromboprophylaxis, and perform subgroup analyses stratified by individual NOACs and different populations after total hip arthroplasty (THA) or total knee arthroplasty (TKA). Literature search was performed in PubMed, EMBASE, Cochrane Library, CNKI and Wanfang databases until June 31, 2022. This systematic review and meta-analysis included 46 randomized controlled trials (RCT) with 39, 924 patients. We evaluated the safety and efficacy of thromboprophylaxis between LMWH and NOACs. NOACs were more effective in reducing deep vein thrombosis (DVT) (RR0.59; 95%CI 0.49-0.71) and adverse events (RR: 0.96; 95%CI: 0.93-0.99) than LMWH. The subgroup analyses for different anticoagulants revealed that rivaroxaban (RR:0.49; 95%CI:0.36-0.66), apixaban (RR: 0.54; 95%CI: 0.36-0.81) and edoxaban (RR:0.49; 95%CI: 0.32-0.75) have the lower risk of DVT than LMWH. Apixaban (RR:0.89; 95%CI: 0.80-1.00) had superior prevention of bleeding to LMWH. Edoxaban exhibited a lower risk of VTE (RR: 0.46; 95%CI: 0.33-0.65), advantage events (RR: 0.87; 95%CI: 0.82-0.93), and drug-related adverse events (DRAEs) (RR: 0.64; 95%CI: 0.53-0.76) than LMWH. East Asian population was superior to western population for preventing DVT, advantage events, and DRAE using NOACs. In conclusion, NOACs are more effective than LMWH at preventing DVT and adverse events after arthroplasty. Apixaban has lower bleeding than LMWH, and East Asian populations may benefit more than western population from NOACs.

Factor Xa Inhibitors and Direct Thrombin Inhibitors Versus Low-Molecular-Weight Heparin for Thromboprophylaxis After Total Hip or Total Knee Arthroplasty: A Systematic Review and Meta-Analysis

BACKGROUND

The purpose of this study is to perform a meta-analysis to compare outcomes of venous thromboembolism (VTE) prophylaxis with low-molecular-weight heparin (LMWH) vs other anticoagulants in patients who received total knee (TKA) or total hip arthroplasty (THA).

METHODS

MEDLINE, Cochrane, EMBASE, and Google Scholar databases were searched until June 30, 2017 for eligible randomized controlled studies.

RESULTS

Thirty-two randomized controlled studies were included. LMWH provided better protection against VTE than placebo. In both TKA and THA patients, the rates of VTE were lower with factor Xa inhibitors than LMWH. In THA patients, the rate of deep vein thrombosis (DVT) was lower with factor Xa inhibitors than LMWH. In TKA patients, the rates of VTE and DVT were similar between LMWH and direct thrombin inhibitors. In THA patients, the rate of VTE was lower with direct thrombin inhibitors than with LMWH, while the DVT rates were similar. The pulmonary embolism rates were similar between all 3 classes of drugs in TKA and THR patients, as were the major bleeding rates. Nonmajor and minor bleeding rates were also similar between the 3 drug classes.

CONCLUSION

LMWH is associated with a higher rate of VTE than factor Xa inhibitors in TKA and THA patients. Direct thrombin inhibitors are associated with a lower rate of VTE in THA patients, but their effectiveness with respect to DVT and pulmonary embolism prophylaxis is similar to that of LMWH in TKA and THA patients.

Low molecular weight heparin versus other anti-thrombotic agents for prevention of venous thromboembolic events after total hip or total knee replacement surgery: a systematic review and meta-analysis

Background

Venous thromboembolism (VTE) is an important complication following total hip replacement (THR) and total knee replacement (TKR) surgeries. Aim of this study was to comprehensively compare the clinical outcomes of low-molecular-weight heparin (LMWH) with other anticoagulants in patients who underwent TKR or THR surgery.

Methods

Medline, Cochrane, EMBASE, and Google Scholar databases were searched for eligible randomized controlled studies (RCTs) published before June 30, 2017. Meta-analyses of odds ratios were performed along with subgroup and sensitivity analyses.

Results

Twenty-one RCTs were included. In comparison with placebo, LMWH treatment was associated with a lower risk of VTE and deep vein thrombosis (DVT) (P values < 0.001) but similar risk of pulmonary embolism (PE) (P = 0.227) in THR subjects. Compared to factor Xa inhibitors, LMWH treatment was associated with higher risk of VTE in TKR subjects (P < 0.001), and higher DVT risk (P < 0.001) but similar risk of PE and major bleeding in both THR and TKR. The risk of either VTE, DVT, PE, or major bleeding was similar between LMWH and direct thrombin inhibitors in both THR and TKR, but major bleeding was lower with LMWH in patients who underwent THR (P = 0.048).

Conclusion

In comparison with factor Xa inhibitors, LMWH may have higher risk of VTE and DVT, whereas compared to direct thrombin inhibitors, LMWH may have lower risk of major bleeding after THR or TKR.

Electronic supplementary material

The online version of this article (10.1186/s12891-018-2215-3) contains supplementary material, which is available to authorized users.

Role of new drugs for management of atrial fibrillation

OBJECTIVE

To evaluate the role of newer agents in the management of atrial fibrillation (AF).

DATA SOURCES

EMBASE and MEDLINE were searched (up to June 2012) combining medication names with atrial fibrillation, humans, clinical trials, and pharmacoeconomic. References of the articles identified and www.clinicaltrials.gov were also reviewed.

STUDY SELECTION AND DATA EXTRACTION

Studies were limited to the English language with clinical or pharmacoeconomic end points followed by the consensus of 3 authors.

DATA SYNTHESIS

Formulated to reduce some of the adverse effects associated with amiodarone by removing the iodine component, dronedarone has improved clinical outcomes over placebo when used in paroxysmal or persistent AF; however, it is less efficacious than amiodarone. Worse outcomes with dronedarone have been seen in patients with heart failure or permanent AF. It has not been compared to antiarrhythmic agents other than amiodarone, and pharmacoeconomic evaluations are lacking. Dabigatran 150 mg is superior to warfarin in preventing stroke or systemic embolism and has been associated with lower rates of vascular-associated mortality. Although the rates of major bleeding were not significantly different between the 2 agents, gastrointestinal bleeding and myocardial infarction occurred more frequently with dabigatran. Dabigatran appears to have the most pharmacoeconomic benefit over warfarin in patients with a higher risk of stroke. Rivaroxaban is noninferior to warfarin for the prevention of stroke and systemic embolism, with no difference in the rates of major bleeding. Cost-effectiveness studies have not been performed with this agent at this time. In patients with AF who were not suitable candidates for warfarin, apixaban is superior to aspirin in preventing stroke or systemic embolism without increasing the risk for major bleeding. Additionally, apixaban is superior to warfarin in preventing stroke or systemic embolism, results in fewer bleeding events, and is associated with lower mortality. Apixaban is not cost-effective against aspirin when used for a short duration but gains superiority with prolonged use or in patients with higher risks of stroke. Additionally, apixaban appears to offer a pharmacoeconomic advantage over warfarin at no to minimal cost. Each new anticoagulant lacks a reversal agent and an assay to detect the presence of the anticoagulant, as well as long-term data when used in the clinical setting.

CONCLUSIONS

Use of dronedarone should be limited to patients with paroxysmal or persistent AF and should not be used in patients with heart failure or with permanent AF. Newer antithrombotic agents appear to be promising alternatives for the prevention of stroke in patients with AF; however, more data are needed to understand their role.

Anticoagulants: newer ones, mechanisms, and perioperative updates

With a growing number of new anticoagulant/antiplatelet agents being developed, it is likely that an increasing number of patients taking these drugs will present for surgery and other procedures. A familiarity with mechanisms of action and drug interactions helps to maintain optimal patient safety in the perioperative period. Furthermore, it is crucial for anesthesiologists to remain current on recommendations regarding discontinuation or need to continue the newer anticoagulants/antiplatelet drugs in patients presenting for surgery and/or regional anesthesia. Further studies are needed for monitoring of many of these newer agents and to identify antidotes.