Abstract Background Non–vitamin K oral anticoagulants (NOACs) do not require routine laboratory monitoring. However, laboratory measurement may be desirable in special situations and populations. ...Objectives This study’s objective was to systematically review and summarize current evidence regarding laboratory measurement of the anticoagulant activity of dabigatran, rivaroxaban, and apixaban. Methods We searched PubMed and Web of Science for studies that reported a relationship between drug levels of dabigatran, rivaroxaban, and apixaban and coagulation assay results. Study quality was evaluated using QUADAS-2 (Quality Assessment of Diagnostic Accuracy Studies 2). Results We identified 17 eligible studies for dabigatran, 15 for rivaroxaban, and 4 for apixaban. For dabigatran, a normal thrombin time excludes clinically relevant drug concentrations. The activated partial thromboplastin time (APTT) and prothrombin time (PT) are less sensitive and may be normal at trough drug levels. The dilute thrombin time (R2 = 0.92 to 0.99) and ecarin-based assays (R2 = 0.92 to 1.00) show excellent linearity across on-therapy drug concentrations and may be used for drug quantification. For rivaroxaban and apixaban, anti-Xa activity is linear (R2 = 0.89 to 1.00) over a wide range of drug levels and may be used for drug quantification. Undetectable anti-Xa activity likely excludes clinically relevant drug concentrations. The PT is less sensitive (especially for apixaban); a normal PT may not exclude clinically relevant levels. The APTT demonstrates insufficient sensitivity and linearity for quantification. Conclusions Dabigatran, rivaroxaban, and apixaban exhibit variable effects on coagulation assays. Understanding these effects facilitates interpretation of test results in NOAC-treated patients. More information on the relationship between drug levels and clinical outcomes is needed.
Abstract Anticoagulation for atrial fibrillation has become more complex due to the introduction of new anticoagulant agents, the number and kinds of patients requiring therapy, and the interactions ...of those patients in the matrix of care. The management of anticoagulation has become a “team sport” involving multiple specialties in multiple sites of care. The American College of Cardiology, through the College’s Anticoagulation Initiative, convened a roundtable of experts from multiple specialties to discuss topics important to the management of patients requiring anticoagulation and to make expert recommendations on issues such as the initiation and interruption of anticoagulation, quality of anticoagulation care, management of major and minor bleeding, and treatment of special populations. The attendees continued to work toward consensus on these topics, and present the key findings of this roundtable in a state-of- the-art review focusing on the practical aspects of anticoagulation care for the patient with atrial fibrillation.
Individuals with hemophilia undergoing hip or knee arthroplasty are at risk for complications such as bleeding and infection. However, data on hospital length of stay (LOS) and readmission rates ...compared with nonhemophilic controls are lacking. This study compared the complication rates, LOS, and unplanned 30-day readmission rates between patients with hemophilia and nonhemophilic controls.
This retrospective cohort study used the Pennsylvania Health Care Cost Containment Council (PHC4) database from 2007 to 2015 to compare outcomes in patients with hemophilia and nonhemophilic controls undergoing partial and total hip arthroplasty, knee arthroplasty, and revision knee arthroplasty.
A total of 118 patients with hemophilia and 3,811 controls were identified. Compared with controls, patients with hemophilia had a higher risk of bleeding complications after hip procedures (38.7% versus 16.1%, p = 0.003), a higher risk of surgical site infection after knee procedures (8.1% versus 1.1%, p < 0.001), longer median LOS after hip (6 versus 3 days, p < 0.001) and knee (5 versus 3 days, p < 0.001) procedures, and higher rates of unplanned 30-day readmission after hip (22.6% versus 4.1%, p < 0.001) and knee (10.3% versus 4.5%, p = 0.018) procedures. The most common reason for unplanned 30-day readmission in patients with hemophilia was bleeding or the patient's underlying coagulopathy (25.1%).
Patients with hemophilia undergoing hip or knee arthroplasty had a higher incidence of postoperative bleeding (hip procedures) and surgical site infections (knee procedures), longer LOS, and higher rates of unplanned 30-day readmission compared with nonhemophilic controls. Key limitations of our study include the potential for inaccurate coding, the relatively small number of patients in the hemophilia cohort, and the uneven distribution of procedure type in the hemophilia and control cohorts.
Prognostic Level III. See Instructions for Authors for a complete description of levels of evidence.
Of these, 6 (1.5%) had a positive SRA (95% confidence interval, 0.7-3.2%). Because the upper limit of the confidence interval (3.2%) exceeded the authors' prespecified boundary for success (3.0%), ...they concluded that a low probability 4Ts score may not be sufficient to rule out HIT in ICU patients. In at least some of these patients, the additional point(s) would have moved the 4Ts score from the low to intermediate probability category. Because the adjudicators lacked clinical information necessary to accurately calculate 1 of the 4 Ts (timing), the true performance of the 4Ts score in ICU patients cannot be definitively deduced from this study.