Rivaroxaban: Expanded Role in Cardiovascular Disease Management—A Literature Review

Direct oral anticoagulants (DOACs) are widely used for the prevention of stroke in nonvalvular atrial fibrillation, treatment of deep venous thrombosis and pulmonary embolism, and as prophylaxis after hip and knee surgery after approval by the Food and Drug Administration. In the last decade, DOACs were studied for various indications; this review is focused on rivaroxaban, a factor Xa inhibitor, which is used in an expanded evidence-based fashion for coronary artery disease, peripheral artery disease, heart failure, malignancy, and prophylaxis of deep venous thrombosis in acute medical illnesses.

Obturator nerve block

One of the forgotten techniques of regional anesthesia is blockade of the obturator nerve, which was performed using anatomical landmarks and neurostimulation. In recent years, ultrasonic navigation methods have gained wide popularity when using regional blockades. The purpose of the review is to present the current understanding of the use of obturator nerve block in clinical practice. The review presents the anatomical features of the obturator nerve passage, surgical and therapeutic indications for the use of its blockade. The technique for performing obturator blockade using ultrasound navigation is described in detail. Blockade of the obturator nerve using ultrasound navigation can reduce the likelihood of surgical complications during transurethral resection of a tumor located on the lateral wall of the bladder, improve analgesia after hip and knee surgery, and effectively relieve spastic conditions of the adductor muscles of the hip.

Trends and developments in hip and knee arthroplasty technology

The developments in hip and knee arthroplasty over recent years have aimed to improve outcomes, reduce complications and improve implant survival. This review describes some of the most interesting trends and developments in this important and fast-moving field. Notable developments have included ceramic hip resurfacing, mini hip stems, cementless knee replacement and the wider adoption of the dual mobility articulation for hip arthroplasty. Advances in additive manufacturing and the surface modification of joint replacements offer increasing options for more challenging arthroplasty cases. Robotic assisted surgery is one of the most interesting developments in hip and knee surgery. The recent growth in the use of this technology is providing data that will help determine whether this approach should become the standard of care for hip and knee arthroplasty in the future.

Reduction in Mortality following Elective Major Hip and Knee Surgery: A Systematic Review and Meta-Analysis

Background Systematic reviews reporting time trends in mortality following major orthopaedic surgery are few and have limitations. They reported on only a fraction (< 15%) of the available data and did not investigate potential causes of the reduction in mortality. Methods We searched PubMed for randomized trials and observational studies, published between 1950 and 2016, reporting on mortality within 3 months of elective total hip and knee replacement (THR/TKR). Mortality risks were estimated for each 5-year interval using a Poisson regression model and presented by study design and mode of prophylaxis. To estimate the mortality reduction unrelated to anti-thrombotic use, we performed a pooled analysis of four thromboprophylaxis strategies for which data spanned five decades. Results We identified 255 eligible studies, which documented 31,604 deaths among 6,293,954 patients, and found a consistent decline in mortality irrespective of study design and mode of prophylaxis. Mortality declined from 1.15% pre-1980 to 0.24% post-2000, a 78.7% relative risk reduction (95% confidence interval [CI]: 74.7–82.1%) in randomized and cohort studies. Furthermore, our data showed a 74.4% (95% CI: 68.7–79.0%) relative reduction in mortality independent of the methods of prophylaxis, thereby indicating that improvements in peri-operative care unrelated to anti-thrombotic prophylaxis played a major role in such reduction. Conclusion Mortality following elective THR/TKR has markedly declined over the past 50 years and is now low irrespective of which prophylactic agent is being used. Although anti-thrombotic prophylaxis may have contributed, other improvements in peri-operative care played a major role in the mortality reduction.

Risk of Venous Thrombosis in Patients with Sickle Cell Trait after Orthopedic Surgery

Introduction Sickle cell trait (SCT) is considered to confer a hypercoagulable state. Historically, venous thromboembolism (VTE, deep vein thrombosis and PE) rates for untreated patients after major orthopedic surgery (hip or knee replacement or hip fracture surgery) have been close to 4.3%, however with the introduction of post-op anticoagulation, the rates have been as low as 1.15%. Although guidelines exist regarding anticoagulation for up to 35 days after major orthopedic surgery, there are no specific recommendations for patients with SCT. The purpose of this retrospective study is to examine the rates of VTE after major orthopedic surgery in a cohort of patients with SCT. We hypothesize that rates of VTE would be higher in patients with SCT and the risk of VTE would persist beyond 35 days. Methods A commercial database (Explorys Inc, Cleveland, OH, USA), an aggregate of electronic health record data from 26 major integrated US healthcare systems representing a sixth of the US population, was queried for data, using Systematized Nomenclature of Medicine (SNOMED) clinical terms or codes. Cases were defined as patients with SCT who underwent major knee or hip surgery. Since a majority of the US population with SCT are African American (AA) patients, controls were defined as AA patients without SCT undergoing major orthopedic surgery. For the primary end point of VTE, only adult patients (≥18 years) were selected. Those with previous history of VTE, thrombophilia, malignant disease, antiphospholipid antibody syndrome and other hemoglobinopathies such as sickle cell disease were excluded. 30 and 90-day rates of VTE were recorded for both groups. Logistic regression models were used to adjust of confounding variables (defined a priori as age > 65 or< 65, smoking, gender and presence or absence of body mass index > 30). Of note, SCT is likely under-estimated due to incomplete diagnosis. Rates or proportions were compared using Chi-squared testusing Medcalc software (2018). Logistic regression analysis was done using Statistical Package for Social Sciences (SPSS, version 21, IBM Corp, Armonk, NY). P< 0.05 was considered statistically significant. Results A total of 1360 major orthopedic surgeries in patients with SCT and 74040 surgeries in non-SCT patients were identified. 30 and 90-day VTE for SCT patients undergoing major orthopedic surgery was 9.7% each. 30 and 90 day VTE for non-SCT patients undergoing major hip and knee surgery were 5.9 % and 6.4 % respectively. The difference in 30-day and 90-day VTE rates between the SCT and non-SCT group was statistically significant (30 day VTE difference 3.1%, 95% CI 1.6650-4.7569, p < 0.001; 90 day VTE difference=3.6%; 95% CI 2.1658-5.2562, p= <0.001). The rates of anticoagulant dispensation (oral Xa inhibitors, enoxaparin or warfarin) after surgery were 56% and 46% in SCT and non-SCT group respectively (difference = 10%, 95% CI 7.32-12.64, p <0.001). Despite the higher proportion of patients prescribed for anticoagulants in the SCT population, there was still a higher 30 and 90-day VTE rate in that group. Compliance to anticoagulation and mortality from VTE could not be assessed in this study. Logistic regression of risk factors associated with risk of VTE revealed age over 65 years of age, female gender, active smoking status, obesity (BMI >30), and presence of sickle cell trait were all significantly associated with increased risk of both 30 and 90 day VTE post major orthopedic surgery. Please see Table 1 and 2 for further details. Conclusion Our study represents real life data outside of a clinical trial. We found that patients with SCT who underwent major hip and knee surgery had an increased 30 and 90-day VTE rates compared to non-SCT patients undergoing the same procedures. Overall, this cohort of AA patients had VTE rates higher than that were described in literature. Of note, AA patients overall are at a higher risk of VTE than are their Caucasian counterparts. The results from the study seem to suggest a role for extended prophylaxis in people with SCT who are undergoing orthopedic procedures, and warrants further study. Disclosures Little: Doris Duke Charitable Foundations: Research Funding; NHLBI: Research Funding; PCORI: Research Funding; Hemex: Patents & Royalties: Patent, no honoraria.