The efficacy and cost-effectiveness of enoxaparin versus rivaroxaban in the prevention of venous thromboembolism following total hip or knee arthroplasty: A meta-analysis

Determination of Rivaroxaban in Rat Plasma by UHPLC-Q-Orbitrap HRMS and Its Application to A Pharmacokinetic Study

Therapeutic drug monitoring is critical to decrease the incidence rate of bleeding and thrombosis for personalized treatment of rivaroxaban, especially for drug interaction treatment, renal dysfunction patients, elderly patients, cardiovascular patients, and so on. And, an accuracy analytical method is necessary to therapeutic drug monitoring. This study developed a ultra high performance liquid chromatography-tandem orbitrap high-resolution mass spectrometry (UHPLC-Q-Orbitrap HRMS) method to accurately identify and quantify rivaroxaban in rat plasma. Isotope internal standard method was applied for accurate quantification. And rivaroxaban-d₄ was selected as isotope internal standard substance. The m/z 436.07263 ([M+H]⁺ ) was selected as precursor ions and the m/z 144.95085, 231.11259 were selected as main product ions for rivaroxaban. The LLOQ of rivaroxaban in plasma was 0.01 mg/L. The intra- and inter-day precisions were ≤3.65 % and ≤8.16 %. And the recoveries were ranged from 87.4% to 95.2%. This analysis method was simple, low cost, and easy to operation and applied successfully to a pharmacokinetic study of rivaroxaban in rat plasma. This analysis method could be helpful to promote further research on the mechanism of rivaroxaban and drug interaction, which can avoid the false positives due to its high precision identification.

Viscoelastic Hemostatic Assays for Orthopedic Trauma and Elective Procedures

The application of viscoelastic hemostatic assays (VHAs) (e.g., thromboelastography (TEG) and rotational thromboelastometry (ROTEM)) in orthopedics is in its relative infancy when compared with other surgical fields. Fortunately, several recent studies describe the emerging use of VHAs to quickly and reliably analyze the real-time coagulation and fibrinolytic status in both orthopedic trauma and elective orthopedic surgery. Trauma-induced coagulopathy—a spectrum of abnormal coagulation phenotypes including clotting factor depletion, inadequate thrombin generation, platelet dysfunction, and dysregulated fibrinolysis—remains a potentially fatal complication in severely injured and/or hemorrhaging patients whose timely diagnosis and management are aided by the use of VHAs. Furthermore, VHAs are an invaluable compliment to common coagulation tests by facilitating the detection of hypercoagulable states commonly associated with orthopedic injury and postoperative status. The use of VHAs to identify hypercoagulability allows for an accurate venous thromboembolism (VTE) risk assessment and monitoring of VTE prophylaxis. Until now, the data have been insufficient to permit an individualized approach with regard to dosing and duration for VTE thromboprophylaxis. By incorporating VHAs into routine practice, orthopedic surgeons will be better equipped to diagnose and treat the complete spectrum of coagulation abnormalities faced by orthopedic patients. This work serves as an educational primer and up-to-date review of the current literature on the use of VHAs in orthopedic surgery.