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Lindsay SE, Working ZM, Friess D, Smith S, Yoo J. Enoxaparin and Early Postoperative Tibial Nailing: Increased Nonunion Revision Rates. J Orthop Trauma 2024; 38:527-533. [PMID: 39325050 DOI: 10.1097/bot.0000000000002873] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 07/10/2024] [Indexed: 09/27/2024]
Abstract
OBJECTIVES To determine the association between postoperative enoxaparin use and the risk of requiring surgery for nonunion in patients treated with intramedullary nailing for midshaft fractures of the tibia. METHODS DESIGN Retrospective cohort analysis. SETTING Data were sourced from the PearlDiver national database. PATIENT SELECTION CRITERIA Patients were identified through the PearlDiver database by using Current Procedural Terminology and International Classification of Diseases (ICD-10) codes. Included patients had undergone intramedullary nailing for midshaft fractures of the tibia between 2015 and 2020 and subsequently underwent revision surgery due to nonunion. OUTCOME MEASURES AND COMPARISONS The primary outcome measured in this study was the rate of nonunion following intramedullary nailing for the different types of tibial shaft fractures (closed, Type I/II open, Type III open). For each fracture subtype, the study compared nonunion rates between those who received enoxaparin in the postoperative period and those who did not receive enoxaparin at any time during the first 6 weeks postoperatively. Factors such as the timing and duration of enoxaparin therapy and demographic variables were also considered. RESULTS The study included 16,986 patients, average age was 49.2 years (SD 17.3); 43.1% were female. Five hundred four patients required revision surgery for nonunion (3.4%). Among patients who did not receive enoxaparin, the nonunion rates were 1.6%, 3.9%, and 6.9% for closed, Type I/II open, and Type III open fractures, respectively. For patients who received enoxaparin within the first 2 weeks, the nonunion rates were 2.6%, 4.7%, and 7.9% for closed (RR = 1.67, P < 0.0001), Type I/II open (RR = 1.21, P < 0.0001), and Type III open (RR = 1.17, P = 0.355) fractures, respectively. Logistic regression confirmed enoxaparin was independently associated with nonunion (odds ratios [OR] = 1.75, P = 0.0013 for closed fractures; OR = 1.51, P = 0.034 for Type I/II open fractures). Tobacco use was also a contributing factor (OR = 2.43, P < 0.0001 for closed fractures; OR = 2.00, P < 0.0001 for Type I/II open fractures; OR = 2.04, P = 0.0008 for Type III open fractures). CONCLUSIONS The postoperative use of enoxaparin was associated with an elevated risk of nonunion in patients treated with intramedullary nailing for fractures of the tibial shaft. LEVEL OF EVIDENCE Prognostic Level III. See Instructions for Authors for a complete description of levels of evidence.
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Bazarbashi S, El Zawahry HM, Owaidah T, AlBader MA, Warsi A, Marashi M, Dawoud E, Jaafar H, Sholkamy SM, Haddad F, Cohen AT. The Role of Direct Oral Anticoagulants in the Treatment of Cancer-Associated Venous Thromboembolism: Review by Middle East and North African Experts. J Blood Med 2024; 15:171-189. [PMID: 38686358 PMCID: PMC11057512 DOI: 10.2147/jbm.s411520] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2023] [Accepted: 03/01/2024] [Indexed: 05/02/2024] Open
Abstract
Venous thromboembolism is a leading cause of morbidity and mortality in patients with active cancer who require anticoagulation treatment. Choice of anticoagulant is based on careful balancing of the risks and benefits of available classes of treatment: vitamin K antagonists, low-molecular-weight heparin (LMWH), and direct oral anticoagulants (DOACs). Results from randomized controlled trials have shown the consistent efficacy of DOACs versus LMWH in the treatment of cancer-associated venous thromboembolism (VTE). However, increased major gastrointestinal bleeding was observed for edoxaban and rivaroxaban, but not apixaban, compared with LMWH dalteparin. Most guidelines recommend DOACs for the treatment of cancer-associated VTE in patients without gastrointestinal or genitourinary cancer, and with considerations for renal impairment and drug-drug interactions. These updates represent a major paradigm shift for clinicians in the Middle East and North Africa. The decision to prescribe a DOAC for a patient with cancer is not always straightforward, particularly in challenging subgroups of patients with an increased risk of bleeding. In patients with gastrointestinal malignancies who are at high risk of major gastrointestinal bleeds, apixaban may be the preferred DOAC; however, caution should be exercised if patients have upper or unresected lower gastrointestinal tumors. In patients with gastrointestinal malignancies and upper or unresected lower gastrointestinal tumors, LMWH may be preferred. Vitamin K antagonists should be used only when DOACs and LMWH are unavailable or unsuitable. In this review, we discuss the overall evidence for DOACs in the treatment of cancer-associated VTE and provide treatment suggestions for challenging subgroups of patients with cancer associated VTE.
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Affiliation(s)
- Shouki Bazarbashi
- Section of Medical Oncology, Oncology Center, King Faisal Specialist Hospital and Research Center, Alfaisal University, Riyadh, Saudi Arabia
| | - Heba Mohamed El Zawahry
- Department of Medical Oncology, The National Cancer Institute, Cairo University, Cairo, Egypt
| | - Tarek Owaidah
- Department of Pathology and Laboratory Medicine, King Faisal Specialist Hospital and Research Center, Alfaisal University, Riyadh, Saudi Arabia
| | | | - Ashraf Warsi
- Department of Adult Hematology, Princess Noorah Oncology Center, King Abdulaziz Medical City, Ministry of National Guard Health Affairs–Western Region, Jeddah, Saudi Arabia
- College of Medicine, King Saud Bin Abdulaziz University for Health Sciences, Ministry of National Guard Health Affairs–Western Region, Jeddah, Saudi Arabia
- King Abdullah International Medical Research Center, Ministry of National Guard Health Affairs-Western Region, Jeddah, Saudi Arabia
| | - Mahmoud Marashi
- Hematology Department, Dubai Hospital, Dubai, United Arab Emirates
- Department of Hematology, Mediclinic City Hospital, Dubai, United Arab Emirates
| | - Emad Dawoud
- Department of Oncology, Tawam Hospital, Al Ain, United Arab Emirates
| | - Hassan Jaafar
- Department of Oncology, Sheikh Khalifa Specialty Hospital, Ras Al-Khaimah, United Arab Emirates
| | | | - Fady Haddad
- Vascular and Endovascular Surgery, American University of Beirut Medical Center, Beirut, Lebanon
| | - Alexander T Cohen
- Department of Haematological Medicine, Guy’s and St Thomas’ Hospitals NHS Foundation Trust, King’s College London, London, UK
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Xie S, Bu C, LaCava J, Chi L. MsPHep: An online application for low molecular weight heparin rapid characterization based on liquid chromatography-tandem mass spectrometry. J Chromatogr A 2023; 1705:464179. [PMID: 37419018 DOI: 10.1016/j.chroma.2023.464179] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2023] [Revised: 06/16/2023] [Accepted: 06/24/2023] [Indexed: 07/09/2023]
Abstract
Low-molecular-weight heparins (LMWHs) are important anticoagulants widely used in clinic. Since they are comprised of complex and heterogenous glycan chains, liquid chromatography-tandem mass spectrometry (LC-MS) is commonly used for structural analysis and quality control of LMWHs to ensure their safety and efficacy. Yet, the structural complexity arising from the parent heparin macromolecules, as well as the different depolymerization methods used for preparing LMWHs, makes processing and assigning the LC-MS data of LWMHs very tedious and challenging. We therefore developed, and here report, an open-source and easy-to-use web application, MsPHep, to facilitate the LMWH analysis based on LC-MS data. MsPHep is compatible with various LMWHs and chromatographic separation methods. With the HepQual function, MsPHep is capable of annotating both the LMWH compound and its isotopic distribution from mass spectra. Moreover, the HepQuant function enables automatic quantification of LMWH compositions without prior knowledge or any database generation. To demonstrate the reliability and system stability of MsPHep, we tested various types of LMWHs that were analyzed with different chromatographic methods coupled to MS. The results show that MsPHep has its own advantages compared to another public tool GlycReSoft for LMWH analysis, and it is available online under an open-source license at https://ngrc-glycan.shinyapps.io/MsPHep.
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Affiliation(s)
- Shaoshuai Xie
- National Glycoengineering Research Center, Shandong University, Qingdao, Shandong 266237, China; European Research Institute for the Biology of Ageing, University Medical Centre Groningen, Groningen 9700AD, Netherlands
| | - Changkai Bu
- National Glycoengineering Research Center, Shandong University, Qingdao, Shandong 266237, China
| | - John LaCava
- European Research Institute for the Biology of Ageing, University Medical Centre Groningen, Groningen 9700AD, Netherlands; Laboratory of Cellular and Structural Biology, The Rockefeller University, New York, NY 10065, USA
| | - Lianli Chi
- National Glycoengineering Research Center, Shandong University, Qingdao, Shandong 266237, China.
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Zhao M, Bao Y, Jiang C, Chen L, Xu L, Liu X, Li J, Yang Y, Jiang G, Li J, She Y, Chen Q, Shen L, Chen C. Rivaroxaban versus nadroparin for thromboprophylaxis following thoracic surgery for lung cancer: A randomized, noninferiority trial. Am J Hematol 2023. [PMID: 37139837 DOI: 10.1002/ajh.26945] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2022] [Revised: 04/12/2023] [Accepted: 04/18/2023] [Indexed: 05/05/2023]
Abstract
The benefit of rivaroxaban in thromboprophylaxis after oncologic lung surgery remains unknown. To evaluate the efficacy and safety of rivaroxaban, patients who underwent thoracic surgery for lung cancer were enrolled, and randomly assigned to rivaroxaban or nadroparin groups in a 1:1 ratio; anticoagulants were initiated 12-24 h after surgery and continued until discharge. Four hundred participants were required according to a noninferiority margin of 2%, assuming venous thromboembolism (VTE) occurrence rates of 6.0% and 12.6% for patients in the rivaroxaban and nadroparin groups, respectively. The primary efficacy outcome was any VTE during the treatment and 30-day follow-up periods. The safety outcome was any on-treatment bleeding event. Finally, 403 patients were randomized (intention-to-treat [ITT] population), with 381 included in per-protocol (PP) population. The primary efficacy outcomes occurred in 12.5% (25/200) of the rivaroxaban group and 17.7% (36/203) of the nadroparin group (absolute risk reduction, -5.2%; 95% confidence interval [CI], [-12.2-1.7]), indicating the noninferiority of rivaroxaban in ITT population. Sensitivity analysis was performed in the PP population and yielded similar results, confirming the noninferiority of rivaroxaban. In the safety analysis population, the incidence of any on-treatment bleeding events did not differ significantly between the groups (12.2% for rivaroxaban vs. 7.0% for nadroparin; relative risk [RR], 1.9; 95% CI, [0.9-3.7]; p = .08), including major bleeding (9.7% vs. 6.5%; RR, 1.6 [95% CI, 0.9-3.7]; p = .24), and nonmajor bleeding (2.6% vs. 0.5%; RR, 5.2 [95% CI, 0.6-45.2]; p = .13). Rivaroxaban for thromboprophylaxis after oncologic lung surgery was shown to be noninferior to nadroparin.
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Affiliation(s)
- Mengmeng Zhao
- Department of Thoracic Surgery, Shanghai Pulmonary Hospital, Tongji University School of Medicine, Shanghai, China
| | - Yi Bao
- Department of Thoracic Surgery, Shanghai Pulmonary Hospital, Tongji University School of Medicine, Shanghai, China
| | - Chao Jiang
- Department of Thoracic Surgery, Shanghai Pulmonary Hospital, Tongji University School of Medicine, Shanghai, China
| | - Linsong Chen
- Department of Thoracic Surgery, Shanghai Pulmonary Hospital, Tongji University School of Medicine, Shanghai, China
| | - Lisha Xu
- Department of Ultrasound, Shanghai Pulmonary Hospital, Tongji University School of Medicine, Shanghai, China
| | - Xiaogang Liu
- Department of Thoracic Surgery, Shanghai Pulmonary Hospital, Tongji University School of Medicine, Shanghai, China
| | - Jiaqi Li
- Department of Thoracic Surgery, Shanghai Pulmonary Hospital, Tongji University School of Medicine, Shanghai, China
| | - Yang Yang
- Department of Thoracic Surgery, Shanghai Pulmonary Hospital, Tongji University School of Medicine, Shanghai, China
| | - Gening Jiang
- Department of Thoracic Surgery, Shanghai Pulmonary Hospital, Tongji University School of Medicine, Shanghai, China
| | - Jian Li
- Clinical Research Center, Ruijin Hospital, Shanghai Jiaotong University School of Medicine, Shanghai, China
| | - Yunlang She
- Department of Thoracic Surgery, Shanghai Pulmonary Hospital, Tongji University School of Medicine, Shanghai, China
| | - Qiankun Chen
- Department of Thoracic Surgery, Shanghai Pulmonary Hospital, Tongji University School of Medicine, Shanghai, China
| | - Lei Shen
- Department of Thoracic Surgery, Shanghai Pulmonary Hospital, Tongji University School of Medicine, Shanghai, China
- Department of Infectious Diseases, Shanghai Key Laboratory of Infectious Diseases and Biosafety Emergency Response, National Medical Center for Infectious Diseases, Huashan Hospital, Fudan University, Shanghai, China
| | - Chang Chen
- Department of Thoracic Surgery, Shanghai Pulmonary Hospital, Tongji University School of Medicine, Shanghai, China
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Enoxaparin versus Unfractionated Heparin for the Perioperative Anticoagulant Therapy in Patients with Mechanical Prosthetic Heart Valve Undergoing Non-Cardiac Surgery. MEDICINA (KAUNAS, LITHUANIA) 2022; 58:medicina58081119. [PMID: 36013586 PMCID: PMC9413761 DOI: 10.3390/medicina58081119] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/01/2022] [Revised: 08/15/2022] [Accepted: 08/17/2022] [Indexed: 11/17/2022]
Abstract
Background and Objectives: Immediate postoperative anticoagulation regimens in patients with mechanical prosthetic valves undergoing non-cardiac surgery are clear only for unfractionated heparin (UH), whereas the few low-molecular-weight heparin (LMWH) trials available to date concern the use of Enoxaparin in general/orthopedic surgery. We performed a single-center real-world data study comparing the efficacy and safety of LMWH—Enoxaparin (E)— and UH during the perioperative period in non-cardiac surgical procedures in patients with mechanical prosthetic valve replacement in the mitral, aortic, or tricuspid positions. Materials and Methods: We enrolled 380 patients, who received E or UH together with oral anticoagulation with antivitamin K (acenocoumarol) until they achieved an optimal International Normalized Ratio (INR). Objective assessment of E efficacy included the following: normal value for all the parameters of ultrasound prosthetic functioning, no early thrombosis of the prosthesis, and rapid achievement of target INR with a decreased period of subcutaneous anticoagulation. Subjective assessment included the following: clinical improvement with decreased immobilization and in-hospital stay, fewer gluteal ulcerations, and fewer postoperative depression and anxiety episodes. Results: Comparing with UH, anticoagulation with E was more effective (p < 0.0001 and p = 0.02). The probability of death was smaller in the E group compared with the UH group. No major hemorrhagic event was reported. Mild bleeding episodes and thrombocytopenia were more common in the UH group. Patient’s compliance and quality of life were better with E due to shortened hospitalization, decreased need for testing of coagulation (every 6 h for UH), better dosing (SC every 12 h for E versus continuous infusion for UH), shortened immobilization during the immediate postoperative period with subsequent improvement in the psychological status, as well as due to lack of significant side effects. Conclusions: Taking into consideration the improved efficiency and safety, as well as all the supplementary advantages, such as no need for anticoagulation monitoring, the ease of administration, and reduced duration of hospitalization, E should be seen as an attractive alternative for anticoagulation which deserves further investigation.
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Tran A, Fernando SM, Carrier M, Siegal DM, Inaba K, Vogt K, Engels PT, English SW, Kanji S, Kyeremanteng K, Lampron J, Kim D, Rochwerg B. Efficacy and Safety of Low Molecular Weight Heparin Versus Unfractionated Heparin for Prevention of Venous Thromboembolism in Trauma Patients: A Systematic Review and Meta-analysis. Ann Surg 2022; 275:19-28. [PMID: 34387202 DOI: 10.1097/sla.0000000000005157] [Citation(s) in RCA: 19] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
PURPOSE Trauma patients are at high risk of VTE. We summarize the efficacy and safety of LMWH versus UFH for the prevention of VTE in trauma patients. METHODS We searched 6 databases from inception through March 12, 2021. We included randomized controlled trials (RCTs) or observational studies comparing LMWH versus UFH for thromboprophylaxis in adult trauma patients. We pooled effect estimates across RCTs and observational studies separately, using random-effects model and inverse variance weighting. We assessed risk of bias using the Cochrane tool for RCTs and the Risk of Bias in Non-Randomized Studies (ROBINS)-I tool for observational studies and assessed certainty of findings using Grading of Recommendations, Assessment, Development and Evaluations methodology. RESULTS We included 4 RCTs (879 patients) and 8 observational studies (306,747 patients). Based on pooled RCT data, compared to UFH, LMWH reduces deep vein thrombosis (RR 0.67, 95% CI 0.50 to 0.88, moderate certainty) and VTE (RR 0.68, 95% CI 0.51 to 0.90, moderate certainty). As compared to UFH, LMWH may reduce pulmonary embolism [adjusted odds ratio from pooled observational studies 0.56 (95% CI 0.50 to 0.62)] and mortality (adjusted odds ratio from pooled observational studies 0.54, 95% CI 0.45 to 0.65), though based on low certainty evidence. There was an uncertain effect on adverse events (RR from pooled RCTs 0.80, 95% CI 0.48 to 1.33, very low certainty) and heparin induced thrombocytopenia [RR from pooled RCTs 0.26 (95% CI 0.03 to 2.38, very low certainty)]. CONCLUSIONS Among adult trauma patients, LMWH is superior to UFH for deep vein thrombosis and VTE prevention and may additionally reduce pulmonary embolism and mortality. The impact on adverse events and heparin induced thrombocytopenia is uncertain.
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Affiliation(s)
- Alexandre Tran
- Division of General Surgery, Department of Surgery, University of Ottawa, Ottawa, Canada
- School of Epidemiology and Public Health, University of Ottawa, Ottawa, Canada
- Division of Critical Care, Department of Medicine, University of Ottawa, Ottawa, Canada
| | - Shannon M Fernando
- Division of Critical Care, Department of Medicine, University of Ottawa, Ottawa, Canada
- Department of Emergency Medicine, University of Ottawa, Ottawa, Canada
| | - Marc Carrier
- School of Epidemiology and Public Health, University of Ottawa, Ottawa, Canada
- Division of Hematology, Department of Medicine, University of Ottawa, Ottawa, Canada
- Clinical Epidemiology Program, Ottawa Hospital Research Institute, Ottawa, Canada
| | - Deborah M Siegal
- School of Epidemiology and Public Health, University of Ottawa, Ottawa, Canada
- Division of Hematology, Department of Medicine, University of Ottawa, Ottawa, Canada
- Clinical Epidemiology Program, Ottawa Hospital Research Institute, Ottawa, Canada
| | - Kenji Inaba
- Division of Acute Care Surgery, Department of Surgery, University of Southern California, Los Angeles
| | - Kelly Vogt
- Division of General Surgery, Department of Surgery, Western University, London, Canada
| | - Paul T Engels
- Division of General Surgery, Department of Surgery, McMaster University, Hamilton, Canada
- Department of Medicine, Division of Critical Care, McMaster University, Hamilton, Canada
| | - Shane W English
- Division of Critical Care, Department of Medicine, University of Ottawa, Ottawa, Canada
- Clinical Epidemiology Program, Ottawa Hospital Research Institute, Ottawa, Canada
| | - Salmaan Kanji
- Division of Critical Care, Department of Medicine, University of Ottawa, Ottawa, Canada
- Clinical Epidemiology Program, Ottawa Hospital Research Institute, Ottawa, Canada
| | - Kwadwo Kyeremanteng
- Division of Critical Care, Department of Medicine, University of Ottawa, Ottawa, Canada
- Clinical Epidemiology Program, Ottawa Hospital Research Institute, Ottawa, Canada
| | - Jacinthe Lampron
- Division of General Surgery, Department of Surgery, University of Ottawa, Ottawa, Canada
| | - Dennis Kim
- Department of Surgery, University of California Los Angeles, Los Angeles, California
| | - Bram Rochwerg
- Department of Medicine, Division of Critical Care, McMaster University, Hamilton, Canada
- Department of Health Research Methods, Evidence, and Impact, McMaster University, Hamilton, ON, Canada
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7
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Low Molecular Weight Heparins (LMWH) and Implications along Pregnancy: a Focus on the Placenta. Reprod Sci 2021; 29:1414-1423. [PMID: 34231172 DOI: 10.1007/s43032-021-00678-0] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/01/2021] [Accepted: 06/18/2021] [Indexed: 10/20/2022]
Abstract
Low molecular weight heparins (LMWH) have been largely studied for their use during pregnancy. The biology and the pharmacology of these molecules are well known and may be summarized in three main mechanisms of action: anti-coagulant, anti-inflammatory, and immunomodulant. The clinical implications of these drugs during pregnancy are mainly related to their action on the placenta, because of the presence of specific molecular and cellular targets, particularly at the trophoblast-endometrial interface. As well as for the prevention and treatment of thromboembolism, LMWH have been largely investigated for the improvement of embryo implantation and for the prevention of placenta-related complications such as preeclampsia, fetal growth restriction, and intrauterine fetal death. However, data on this topic are still unclear. The present review discusses the biological features, the mechanisms of action, and the possible contribution of LMWH to the success of placentation along pregnancy, pointing out the need for future basic science and clinical researches in this important field with the final aim to improve clinical practice in high-risk pregnancies.
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Liu DS, Stevens S, Wong E, Fong J, Mori K, Fleming N, Beh PS, Crowe A, Howard T, Slevin M, Jain A, Gill AS, Lee S, Jamel W, Bennet S, Chung C, Ward S, Muralidharan V. Variations in practice of thromboprophylaxis across general surgical subspecialties: a multicentre (PROTECTinG) study of elective major surgeries. ANZ J Surg 2020; 90:2441-2448. [PMID: 33124123 DOI: 10.1111/ans.16374] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2020] [Revised: 09/20/2020] [Accepted: 09/21/2020] [Indexed: 11/29/2022]
Abstract
BACKGROUND Despite guidelines recommending perioperative thromboprophylaxis for patients undergoing general surgery, we have observed significant variations in its practice. This may compromise patient safety. Here, we quantify the heterogeneity of perioperative thromboprophylaxis across all major general surgical operations, and place them in relation to their risk of bleeding and venous thromboembolism. METHODS Retrospective review of all elective major general surgeries performed between 1 January 2018 and 30 June 2019 across seven Victorian hospitals was conducted. RESULTS A total of 5912 patients who underwent 6628 procedures were reviewed. Significant heterogeneity was found in the use of chemoprophylaxis, timing of its initiation, type of anticoagulant administered and application of extended chemoprophylaxis. These variations were observed within the same procedure, and between different surgeries and subspecialties. Contrastingly, there was minimal heterogeneity with the use of mechanical thromboprophylaxis. Oesophago-gastric, liver and colorectal cancer resections had the highest thromboembolic risk. Breast, oesophago-gastric, liver, pancreas and colon cancer resections had the highest bleeding risk. CONCLUSION Perioperative chemoprophylaxis across general surgery is highly variable. This study has highlighted key areas of variance. Our findings also enable surgeons to compare their practices, and provide baseline data to inform future efforts towards optimizing thromboprophylaxis for general surgical patients.
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Affiliation(s)
- David S Liu
- Department of Surgery, Austin Health, Melbourne, Victoria, Australia.,Department of Surgery, Northern Health, Melbourne, Victoria, Australia.,Department of Surgery and Perioperative Medicine, Flinders Medical Centre, Adelaide, South Australia, Australia
| | - Sean Stevens
- Department of Surgery, Austin Health, Melbourne, Victoria, Australia.,Austin Precinct, Department of Surgery, The University of Melbourne, Melbourne, Victoria, Australia
| | - Enoch Wong
- Department of Surgery, Box Hill Hospital, Melbourne, Victoria, Australia
| | - Jonathan Fong
- Department of Surgery, Austin Health, Melbourne, Victoria, Australia
| | - Krinal Mori
- Department of Surgery, Austin Health, Melbourne, Victoria, Australia.,Department of Surgery, Northern Health, Melbourne, Victoria, Australia.,Northern Precinct, Department of Surgery, The University of Melbourne, Melbourne, Victoria, Australia
| | - Nicola Fleming
- Department of Surgery, Austin Health, Melbourne, Victoria, Australia
| | - Pith Soh Beh
- Department of Surgery, Northern Health, Melbourne, Victoria, Australia
| | - Amy Crowe
- Department of Surgery, Box Hill Hospital, Melbourne, Victoria, Australia
| | - Tess Howard
- Department of Surgery, Austin Health, Melbourne, Victoria, Australia
| | - Maeve Slevin
- Department of Surgery, Northern Health, Melbourne, Victoria, Australia
| | - Anshini Jain
- Department of Surgery, Box Hill Hospital, Melbourne, Victoria, Australia
| | - Anna Sonia Gill
- Department of Surgery, Austin Health, Melbourne, Victoria, Australia
| | - Sharon Lee
- Department of Surgery, Northern Health, Melbourne, Victoria, Australia
| | - Wael Jamel
- Department of Surgery, Austin Health, Melbourne, Victoria, Australia
| | - Simon Bennet
- Department of Surgery, Austin Health, Melbourne, Victoria, Australia
| | - Chi Chung
- Department of Surgery, Box Hill Hospital, Melbourne, Victoria, Australia
| | - Salena Ward
- Department of Surgery, Box Hill Hospital, Melbourne, Victoria, Australia.,Monash University Eastern Health Clinical School, Melbourne, Victoria, Australia
| | - Vijayaragavan Muralidharan
- Department of Surgery, Austin Health, Melbourne, Victoria, Australia.,Austin Precinct, Department of Surgery, The University of Melbourne, Melbourne, Victoria, Australia
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- Department of Surgery, Austin Health, Melbourne, Victoria, Australia
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9
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Cappello B, Moja L, Figueras A, Magrini N. The "Square Box": Therapeutic Equivalence as a Foundation of the WHO Model List of Essential Medicines. Front Pharmacol 2020; 11:578000. [PMID: 33071791 PMCID: PMC7533616 DOI: 10.3389/fphar.2020.578000] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2020] [Accepted: 08/26/2020] [Indexed: 12/02/2022] Open
Abstract
Every two years, the World Health Organization (WHO) updates its Model List of Essential Medicines, intended as a guide for countries to adopt or adapt in accordance with local priorities and treatment guidelines, for the development of national essential medicines lists. When more than one therapeutic option is available for a given indication, the WHO Model List often includes a single medicine as representative of a group of equivalent and interchangeable medicines. The representative medicine of that group is listed with an accompanying ‘square box’ symbol. The intended purpose of the square box is to highlight pharmacological classes or groups of medicines for which countries, institutions and health professionals can assume homogeneous therapeutic efficacy and safety and select the most appropriate single medicine based on price, local availability, and acceptability. Though this concept of therapeutic equivalence within a therapeutic class has been endorsed by most authoritative textbooks of pharmacology since Goodman & Gilman’s The Pharmacological Basis of Therapeutics and evidence-based guidelines, marketing forces have often made claims on individual drugs to distinguish them beyond relevant differences shown by reliable evidence: this has generated the concept of “me-too drugs” with its double meaning—i.e., market latecomers differing minimally from products preceding them and whose marketing budgets have significant opportunity costs, or medicines which may be useful to substitute for equivalent products in the event of shortages. The square box concept is applied in the context of a comprehensive list: therapeutic equivalence or interchangeability cannot always be easily established. Different interpretations have been applied to different groups of medicines over the 40+ year history of the Model List. This paper presents the concept of the square box, provides key examples and guidance on how square box listings should be practically interpreted in the development and implementation of national essential medicine lists, considers the applicability of a square box listing concept to biologic medicines and proposes that an updated review of the square box concept and listings is warranted.
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Affiliation(s)
- Bernadette Cappello
- Department of Health Products Policy and Standards, World Health Organization, Geneva, Switzerland
| | - Lorenzo Moja
- Department of Health Products Policy and Standards, World Health Organization, Geneva, Switzerland
| | - Albert Figueras
- Department of Health Products Policy and Standards, World Health Organization, Geneva, Switzerland.,Department of Pharmacology, Therapeutics and Toxicology, Universitat Autònoma de Barcelona, Barcelona, Spain
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Fang G, Tang B. Advanced delivery strategies facilitating oral absorption of heparins. Asian J Pharm Sci 2020; 15:449-460. [PMID: 32952668 PMCID: PMC7486512 DOI: 10.1016/j.ajps.2019.11.006] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2019] [Revised: 09/23/2019] [Accepted: 11/21/2019] [Indexed: 12/20/2022] Open
Abstract
Heparins show great anticoagulant effect with few side effects, and are administered by subcutaneous or intravenous route in clinics. To improve patient compliance, oral administration is an alternative route. Nonetheless, oral administration of heparins still faces enormous challenges due to the multiple obstacles. This review briefly analyzes a series of barriers ranging from poorly physicochemical properties of heparins, to harsh biological barriers including gastrointestinal degradation and pre-systemic metabolism. Moreover, several approaches have been developed to overcome these obstacles, such as improving stability of heparins in the gastrointestinal tract, enhancing the intestinal epithelia permeability and facilitating lymphatic delivery of heparins. Overall, this review aims to provide insights concerning advanced delivery strategies facilitating oral absorption of heparins.
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Affiliation(s)
- Guihua Fang
- School of Pharmacy, Nantong University, 19 Qixiu Road, Nantong 226001, China
| | - Bo Tang
- School of Pharmacy, Nantong University, 19 Qixiu Road, Nantong 226001, China
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Ripsman D, Fergusson DA, Montroy J, Auer RC, Huang JW, Dobriyal A, Wesch N, Carrier M, Lalu MM. A systematic review on the efficacy and safety of low molecular weight heparin as an anticancer therapeutic in preclinical animal models. Thromb Res 2020; 195:103-113. [PMID: 32683148 DOI: 10.1016/j.thromres.2020.07.008] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2020] [Revised: 07/03/2020] [Accepted: 07/06/2020] [Indexed: 01/30/2023]
Abstract
OBJECTIVE The therapeutic effects of low molecular weight heparins (LMWH) may extend past thrombosis prevention, with preclinical evidence demonstrating anti-metastatic properties. Clinical evidence on the topic, however, remains controversial. A systematic review of preclinical evidence may help elucidate reasons for this contradictory evidence. The objective of our systematic review is to assess the anti-metastatic properties of LMWHs in solid tumour animal models. METHODS MEDLINE, Embase, Web of Science and PubMed were searched from inception to May 12th, 2020. All articles were screened independently and in duplicate. Studies that compared LMWH to a placebo or no treatment arm in solid tumour animal models were included. The primary outcome was the burden of metastasis. Secondary outcomes included primary tumour growth and mortality. The risk of bias was assessed in duplicate using a modified Cochrane Risk of Bias tool. RESULTS Forty-two studies were included in the review. Administration of a LMWH was associated with a significant decrease in the burden of metastasis (SMD -2.18; 95% CI -2.66 to -1.70). Additionally, the administration of a LMWH was also associated with a significant reduction in primary tumour growth (SMD -1.95; 95% CI -2.56 to -1.34) and risk of death (RR 0.39; 95% CI 0.16-0.97). All included studies were deemed to be at an unclear risk of bias for at least one methodological criterion. CONCLUSIONS Our results demonstrate that LMWH can effectively reduce metastatic burden and reduce tumour growth in preclinical animal models of solid tumour malignancies. Reasons for the contradiction with clinical evidence require further exploration.
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Affiliation(s)
- David Ripsman
- Clinical Epidemiology Program, Ottawa Hospital Research Institute, 501 Smyth Box 511, Ottawa, ON K1H 8L6, Canada; Faculty of Medicine, University of Ottawa, 451 Smyth Rd #2044, Ottawa, ON K1H 8M5, Canada.
| | - Dean A Fergusson
- Clinical Epidemiology Program, Ottawa Hospital Research Institute, 501 Smyth Box 511, Ottawa, ON K1H 8L6, Canada; Faculty of Medicine, University of Ottawa, 451 Smyth Rd #2044, Ottawa, ON K1H 8M5, Canada.
| | - Joshua Montroy
- Clinical Epidemiology Program, Ottawa Hospital Research Institute, 501 Smyth Box 511, Ottawa, ON K1H 8L6, Canada.
| | - Rebecca C Auer
- Department of Surgery, The Ottawa Hospital, 501 Smyth Road, Ottawa, ON K1H 8L6, Canada; Cancer Therapeutics Program, Ottawa Hospital Research Institute, 501 Smyth Box 511, Ottawa, ON K1H 8L6, Canada.
| | - Johnny W Huang
- Faculty of Medicine, University of Ottawa, 451 Smyth Rd #2044, Ottawa, ON K1H 8M5, Canada.
| | - Aditi Dobriyal
- Clinical Epidemiology Program, Ottawa Hospital Research Institute, 501 Smyth Box 511, Ottawa, ON K1H 8L6, Canada; Faculty of Medicine, University of Ottawa, 451 Smyth Rd #2044, Ottawa, ON K1H 8M5, Canada.
| | - Neil Wesch
- Clinical Epidemiology Program, Ottawa Hospital Research Institute, 501 Smyth Box 511, Ottawa, ON K1H 8L6, Canada
| | - Marc Carrier
- Clinical Epidemiology Program, Ottawa Hospital Research Institute, 501 Smyth Box 511, Ottawa, ON K1H 8L6, Canada; Faculty of Medicine, University of Ottawa, 451 Smyth Rd #2044, Ottawa, ON K1H 8M5, Canada.
| | - Manoj M Lalu
- Clinical Epidemiology Program, Ottawa Hospital Research Institute, 501 Smyth Box 511, Ottawa, ON K1H 8L6, Canada; Department of Anesthesiology and Pain Medicine, The Ottawa Hospital, Room B307, 1053 Carling Avenue, Mail Stop 249, Ottawa, ON K1Y 4E9, Canada; Regenerative Medicine Program, Ottawa Hospital Research Institute, 501 Smyth Box 511, Ottawa, ON K1H 8L6, Canada.
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12
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Monitoring the hemostasis process through the electrical characteristics of a graphene-based field-effect transistor. Biosens Bioelectron 2020; 157:112167. [DOI: 10.1016/j.bios.2020.112167] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2019] [Revised: 02/05/2020] [Accepted: 03/20/2020] [Indexed: 11/18/2022]
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13
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Interventional Spine and Pain Procedures in Patients on Antiplatelet and Anticoagulant Medications (Second Edition). Reg Anesth Pain Med 2017; 43:225-262. [DOI: 10.1097/aap.0000000000000700] [Citation(s) in RCA: 56] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
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14
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Abstract
In patients with atrial fibrillation (AF), oral anticoagulation is used to prevent stroke and systemic embolism. In a common clinical scenario, AF patients frequently undergo invasive procedures requiring temporary interruption of oral anticoagulation, thereby potentially exposing such patients to increased risk of thromboembolism. Bridging anticoagulation has been used clinically to mitigate this perceived thromboembolic risk, though this practice may also increase risk of periprocedural bleeding. High-quality data has not previously existed to inform decision-making in this clinical situation of bridging anticoagulation. We discuss recent results from the BRIDGE trial and secondary analyses from recent phase 3 randomized clinical trials of direct-acting oral anticoagulant (DOAC) use in non-valvular AF, that inform periprocedural anticoagulation with bridging strategies in AF patients. Updated data from these current trials favor against a strategy of bridging anticoagulation for elective procedures in the majority of AF patients, low or moderate in thromboembolic risk. Bridging anticoagulation is associated with an increased risk of bleeding and no decreased risk of thromboembolism.
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van Rein N, Biedermann JS, van der Meer FJM, Cannegieter SC, Wiersma N, Vermaas HW, Reitsma PH, Kruip MJHA, Lijfering WM. Major bleeding risks of different low-molecular-weight heparin agents: a cohort study in 12 934 patients treated for acute venous thrombosis. J Thromb Haemost 2017; 15:1386-1391. [PMID: 28440008 DOI: 10.1111/jth.13715] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2016] [Indexed: 01/09/2023]
Abstract
Essentials Low-molecular-weight-heparins (LMWH) kinetics differ which may result in different bleeding risks. A cohort of 12 934 venous thrombosis patients on LMWH was followed until major bleeding. The absolute major bleeding risk was low among patients registered at the anticoagulation clinic. Once-daily dosing was associated with a lower bleeding risk as compared with twice-daily. SUMMARY Background Low-molecular-weight heparins (LMWHs) are considered members of a class of drugs with similar anticoagulant properties. However, pharmacodynamics and pharmacokinetics between LMWHs differ, which may result in different bleeding risks. As these agents are used by many patients, small differences may lead to a large effect on numbers of major bleeding events. Objectives To determine major bleeding risks for different LMWH agents and dosing schedules. Methods A cohort of acute venous thrombosis patients from four anticoagulation clinics who used an LMWH and a vitamin K antagonist were followed until they ceased LMWH treatment or until major bleeding. Exposures were classified according to different types of LMWHs and for b.i.d. and o.d. use. Cumulative incidences for major bleeding per 1000 patients and risk ratios were calculated and adjusted for study center. Results The study comprised 12 934 patients with a mean age of 59 years; 6218 (48%) were men. The cumulative incidence of major bleeding was 2.5 per 1000 patients (95% confidence interval [CI], 1.7-3.5). Enoxaparin b.i.d. or o.d. was associated with a relative bleeding risk of 1.7 (95% CI, 0.2-17.5) compared with nadroparin o.d. In addition, a nadroparin b.i.d. dosing schedule was associated with a 2.0-fold increased major bleeding risk (95% CI, 0.8-5.1) as compared with a nadroparin o.d. dosing schedule. Conclusions Absolute major bleeding rates were low for all LMWH agents and dosing schedules in a large unselected cohort. Nevertheless, twice-daily dosing with nadroparin appeared to be associated with an increased major bleeding risk as compared with once-daily dosing, as also suggested in a meta-analysis of controlled clinical trials.
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Affiliation(s)
- N van Rein
- Department of Thrombosis and Hemostasis, Leiden University Medical Center, Leiden, the Netherlands
- Einthoven Laboratory for Experimental Vascular Medicine, Leiden University Medical Center, Leiden, the Netherlands
| | - J S Biedermann
- Department of Hematology, Erasmus University Medical Center, Rotterdam, the Netherlands
- Star-Medical Diagnostic Center, Rotterdam, the Netherlands
| | - F J M van der Meer
- Department of Thrombosis and Hemostasis, Leiden University Medical Center, Leiden, the Netherlands
| | - S C Cannegieter
- Department of Clinical Epidemiology, Leiden University Medical Center, Leiden, the Netherlands
| | - N Wiersma
- Anticoagulation Clinic Utrecht, Utrecht, the Netherlands
| | - H W Vermaas
- Anticoagulation Clinic The Hague, The Hague, the Netherlands
| | - P H Reitsma
- Department of Thrombosis and Hemostasis, Leiden University Medical Center, Leiden, the Netherlands
- Einthoven Laboratory for Experimental Vascular Medicine, Leiden University Medical Center, Leiden, the Netherlands
| | - M J H A Kruip
- Department of Hematology, Erasmus University Medical Center, Rotterdam, the Netherlands
- Star-Medical Diagnostic Center, Rotterdam, the Netherlands
| | - W M Lijfering
- Department of Thrombosis and Hemostasis, Leiden University Medical Center, Leiden, the Netherlands
- Einthoven Laboratory for Experimental Vascular Medicine, Leiden University Medical Center, Leiden, the Netherlands
- Department of Clinical Epidemiology, Leiden University Medical Center, Leiden, the Netherlands
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Manfredi AA, Rovere-Querini P, D'Angelo A, Maugeri N. Low molecular weight heparins prevent the induction of autophagy of activated neutrophils and the formation of neutrophil extracellular traps. Pharmacol Res 2017; 123:146-156. [PMID: 28161237 DOI: 10.1016/j.phrs.2016.08.008] [Citation(s) in RCA: 70] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/28/2016] [Revised: 08/04/2016] [Accepted: 08/04/2016] [Indexed: 12/12/2022]
Abstract
The protection exerted by neutrophils against invading microbes is partially mediated via the generation of neutrophil extracellular traps (NETs). In sterile conditions NETs are damaging species, enriched in autoantigens and endowed with the ability to damage the vessel wall and bystander tissues, to promote thrombogenesis, and to impair wound healing. To identify and reposition agents that can be used to modulate the formation of NETs is a priority in the research agenda. Low molecular weight heparins (LMWH) are currently used, mostly on an empirical basis, in conditions in which NETs play a critical role, such as pregnancy complications associated to autoimmune disease. Here we report that LMWHs induce a profound change in the ability of human neutrophils to generate NETs and to mobilize the content of the primary granules in response to unrelated inflammatory stimuli, such as IL-8, PMA and HMGB1. Autophagy consistently accompanies NET generation in our system and autophagy inhibitors, 3-MA and wortmannin, prevent NET generation. Pretreatment with LMWH in vitro critically jeopardizes neutrophil ability to activate autophagy, a mechanism that might contribute to neutrophil unresponsiveness. Finally, we verified that treatment of healthy volunteers with a single prophylactic dose of parnaparin abrogated the ability of neutrophils to activate autophagy and to generate NETs. Together, these results support the contention that neutrophils, and NET generation in particular, might represent a preferential target of the anti-inflammatory action of LMWH.
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Affiliation(s)
- Angelo A Manfredi
- Division of Immunology, Transplantation and Infectious Diseases, San Raffaele Scientific Institute, Milano, Italy; Vita-Salute San Raffaele University, Milano, Italy
| | - Patrizia Rovere-Querini
- Division of Immunology, Transplantation and Infectious Diseases, San Raffaele Scientific Institute, Milano, Italy; Vita-Salute San Raffaele University, Milano, Italy
| | - Armando D'Angelo
- Coagulation Service and Thrombosis Research Unit, San Raffaele Scientific Institute, Milan, Italy
| | - Norma Maugeri
- Division of Immunology, Transplantation and Infectious Diseases, San Raffaele Scientific Institute, Milano, Italy.
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Thomas O, Larsson A, Tynngård N, Schött U. Thromboelastometry versus free-oscillation rheometry and enoxaparin versus tinzaparin: an in-vitro study comparing two viscoelastic haemostatic tests' dose-responses to two low molecular weight heparins at the time of withdrawing epidural catheters from ten patients after major surgery. BMC Anesthesiol 2015; 15:170. [PMID: 26603039 PMCID: PMC4659161 DOI: 10.1186/s12871-015-0145-2] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2015] [Accepted: 11/11/2015] [Indexed: 11/24/2022] Open
Abstract
Background Monitoring low molecular weight heparins (LMWH’s) in the perioperative period is prudent in patients at high risk of coagulative complications, especially when the patient has an epidural catheter requiring withdrawal, which is associated with the risk of spinal haematoma. The aim of this study was to evaluate the in vitro dose-responses of two different LMWH’s on two different viscoelastic haemostatic tests, using blood sampled from patients with normal routine coagulation parameters, on the day after major surgery when their epidural catheters were due to be withdrawn. Methods Enoxaparin or tinzaparin were added in vitro to blood from ten patients who had undergone oesophageal resection, to obtain plasma concentrations of approximately 0, 0.5, 1.0 and 1.5 IU/mL. Coagulation was monitored using thromboelastometry (ROTEM®) using the InTEM® activating reagent; and free oscillation rheometry (FOR: ReoRox®), activated using thromboplastin. Clot initiation was measured using ROTEM-CT, ReoRox-COT1 and ReoRox–COT2. Clot propagation was measured using ROTEM-CFT, ROTEM-Alpha Angle and ReoRox-Slope. Clot stability was measured using ROTEM-MCF and ReoRox-G’max, and clot lysis was measured using ROTEM-ML and ReoRox-ClotSR. Results Clot initiation time assessed by thromboelastometry and FOR was prolonged by increasing concentrations of both LMWH’s (P < 0.01). Equivalent doses of tinzaparin in international units (anti-FXa units) per millilitre prolonged clot initiation more than enoxaparin (P < 0.05). There was significant inter-individual variation – the ranges of CT and COT1 at LMWH-concentrations of 0 and 1.5 IU/mL overlapped. None of the tests reflecting clot formation rate or stability showed a dose–response to either LMWH but clot lysis showed a tentative negative dose–response to the LMWH’s. Conclusions Clot initiation time’s dose-dependent prolongation by LMWH’s in this study agrees with previous research, as does tinzaparin’s stronger anti-coagulative effect than enoxaparin at equivalent levels of anti-FXa activity. This casts doubt on the validity of using anti-FXa assays alone to guide dosage of LMWH’s. The significant inter-individual variation in dose–response suggests that the relationship between dose and effect in the postoperative period is complicated. While both ROTEM and FOR may have some role in postoperative monitoring, more research is needed before any conclusion can be made about their clinical usefulness. Electronic supplementary material The online version of this article (doi:10.1186/s12871-015-0145-2) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Owain Thomas
- Medical Faculty, University of Lund, Lund, Sweden. .,Department of Paediatric Anaesthesia and Intensive Care, SUS Lund University Hospital, Lund, Sweden.
| | - Anna Larsson
- Medical Faculty, University of Lund, Lund, Sweden
| | - Nahreen Tynngård
- Department of Clinical Immunology and Transfusion Medicine, Department of Clinical and Experimental Medicine, Linköping University, Linköping, Sweden.,Department of Clinical Chemistry, Department of Clinical Experimental Medicine, Linköping University, Linköping, Sweden
| | - Ulf Schött
- Medical Faculty, University of Lund, Lund, Sweden.,Department of Anaesthesia and Intensive Care, SUS Lund University Hospital, Lund, Sweden
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Yuksel H, Kayatas S, Boza AT, Api M, Ertekin AA, Cam C. Low molecular weight heparin use in unexplained recurrent miscarriage. Pak J Med Sci 2015; 30:1232-7. [PMID: 25674114 PMCID: PMC4320706 DOI: 10.12669/pjms.306.5477] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2014] [Revised: 08/13/2014] [Accepted: 08/13/2014] [Indexed: 11/29/2022] Open
Abstract
Objective: The aim of the study was to investigate whether the use of low molecular weight heparin (LMWH) improve live birth rates when compared with control group in patients with unexplained recurrent miscarriages (URM). Methods: In this prospective observational study 150 women with a history of two or more previous unexplained first trimester pregnancy loss who received LMWH; either enoxaparin (n=50), tinzaparin (n=50) or nothing (n=50) were followed for the pregnancy outcome measures. Only the patients who have used standardized dosage of LMWH (4000 IU/day enoxaparin or 3500 IU/day tinzaparin ) were included to the study. The primary end point was the live birth rate and secondary end points were the side effects, late pregnancy complications and neonatal outcome in the study cohorts. Results: Live birth was achieved 85% of the LMWH group and 66% of the control group (p=0.007). According to the subgroup analysis; live birth rates did not differ significantly between the enoxaparin and tinzaparin group (84% and 86%, respectively). Maternal and neonatal side effects were not statistically significant among the study participants. Conclusion: Thromboprophylaxis with LMWH resulted in a improved live-birth rate in patient with 2 or more consecutive unexplained recurrent pregnancy loss. Nevertheless these findings need to be confirmed in larger randomized trials.
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Affiliation(s)
- Halide Yuksel
- Halide Yuksel, Zeynep Kamil Women and Children Diseases Training and Research Hospital, Department of Obstetrics and Gynecology, Istanbul, Turkey, 34668
| | - Semra Kayatas
- Semra Kayatas, Zeynep Kamil Women and Children Diseases Training and Research Hospital, Department of Obstetrics and Gynecology, Istanbul, Turkey, 34668
| | - Aysen Telce Boza
- Aysen Telce Boza, Zeynep Kamil Women and Children Diseases Training and Research Hospital, Department of Obstetrics and Gynecology, Istanbul, Turkey, 34668
| | - Murat Api
- Murat Api, Zeynep Kamil Women and Children Diseases Training and Research Hospital, Department of Obstetrics and Gynecology, Istanbul, Turkey, 34668
| | - A Aktug Ertekin
- A.Aktug Ertekin, Zeynep Kamil Women and Children Diseases Training and Research Hospital, Department of Obstetrics and Gynecology, Istanbul, Turkey, 34668
| | - Cetin Cam
- Cetin Cam, Zeynep Kamil Women and Children Diseases Training and Research Hospital, Department of Obstetrics and Gynecology, Istanbul, Turkey, 34668
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Monitoring low molecular weight heparins at therapeutic levels: dose-responses of, and correlations and differences between aPTT, anti-factor Xa and thrombin generation assays. PLoS One 2015; 10:e0116835. [PMID: 25625201 PMCID: PMC4308107 DOI: 10.1371/journal.pone.0116835] [Citation(s) in RCA: 50] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2014] [Accepted: 12/15/2014] [Indexed: 11/19/2022] Open
Abstract
Background Low molecular weight heparins (LMWH’s) are used to prevent and treat thrombosis. Tests for monitoring LMWH’s include anti-factor Xa (anti-FXa), activated partial thromboplastin time (aPTT) and thrombin generation. Anti-FXa is the current gold standard despite LMWH’s varying affinities for FXa and thrombin. Aim To examine the effects of two different LMWH’s on the results of 4 different aPTT-tests, anti-FXa activity and thrombin generation and to assess the tests’ concordance. Method Enoxaparin and tinzaparin were added ex-vivo in concentrations of 0.0, 0.5, 1.0 and 1.5 anti-FXa international units (IU)/mL, to blood from 10 volunteers. aPTT was measured using two whole blood methods (Free oscillation rheometry (FOR) and Hemochron Jr (HCJ)) and an optical plasma method using two different reagents (ActinFSL and PTT-Automat). Anti-FXa activity was quantified using a chromogenic assay. Thrombin generation (Endogenous Thrombin Potential, ETP) was measured on a Ceveron Alpha instrument using the TGA RB and more tissue-factor rich TGA RC reagents. Results Methods’ mean aPTT at 1.0 IU/mL LMWH varied between 54s (SD 11) and 69s (SD 14) for enoxaparin and between 101s (SD 21) and 140s (SD 28) for tinzaparin. ActinFSL gave significantly shorter aPTT results. aPTT and anti-FXa generally correlated well. ETP as measured with the TGA RC reagent but not the TGA RB reagent showed an inverse exponential relationship to the concentration of LMWH. The HCJ-aPTT results had the weakest correlation to anti-FXa and thrombin generation (Rs0.62–0.87), whereas the other aPTT methods had similar correlation coefficients (Rs0.80–0.92). Conclusions aPTT displays a linear dose-respone to LMWH. There is variation between aPTT assays. Tinzaparin increases aPTT and decreases thrombin generation more than enoxaparin at any given level of anti-FXa activity, casting doubt on anti-FXa’s present gold standard status. Thrombin generation with tissue factor-rich activator is a promising method for monitoring LMWH’s.
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Abstract
Venous thromboembolism (VTE) can occur after major general surgery. Pulmonary embolism is recognized as the most common identifiable cause of death in hospitalized patients in the United States. The risk of deep venous thrombosis (DVT) and pulmonary embolism (PE) is higher in colorectal surgical procedures compared with general surgical procedures. The incidence of venous thromboembolism in this population is estimated to be 0.2 to 0.3%. Prevention of VTE is considered a patient-safety measure in most mandated quality initiatives. The measures for prevention of VTE include mechanical methods (graduated compression stockings and intermittent pneumatic compression devices) and pharmacologic agents. A combination of mechanical and pharmacologic methods produces the best results. Patients undergoing surgery should be stratified according to their risk of VTE based on patient risk factors, disease-related risk factors, and procedure-related risk factors. The type of prophylaxis should be commensurate with the risk of VTE based on the composite risk profile.
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Affiliation(s)
- Jonathan Laryea
- Division of Colon and Rectal Surgery, Department of surgery, University of Arkansas for Medical Sciences, Little Rock, Arkansas
| | - Bradley Champagne
- Division of Colon and Rectal Surgery, Department of surgery, Case Western Reserve University, Cleveland, Ohio
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Dooley C, Kaur R, Sobieraj DM. Comparison of the efficacy and safety of low molecular weight heparins for venous thromboembolism prophylaxis in medically ill patients. Curr Med Res Opin 2014; 30:367-80. [PMID: 23971722 DOI: 10.1185/03007995.2013.837818] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
OBJECTIVE To conduct a systematic review and mixed-treatment comparison (MTC) meta-analysis to compare the efficacy and safety of low molecular weight heparins (LMWHs) for venous thromboembolism (VTE) prophylaxis in hospitalized medically ill patients. As a secondary objective we compared all therapies within the network to each other. METHODS We conducted a systematic literature search for randomized trials that evaluated pharmacologic VTE prophylaxis in hospitalized medically ill patients. We conducted a traditional meta-analysis for all pairwise comparisons using a random effects model, reporting relative risks (RRs) and 95% confidence intervals for each outcome. To determine the relative efficacy and safety of included therapies we conducted a MTC meta-analysis using a Bayesian framework, reporting odds ratios (OR) and 95% credible intervals. RESULTS Twenty trials met inclusion criteria. Enoxaparin, dalteparin, nadroparin and certoparin were the LMWHs evaluated although none in direct comparative trials. Upon MTC, the relative efficacy of all LMWHs was similar in preventing mortality and VTE as well as in the odds of major and minor bleeding. Dalteparin was not included in the network to evaluate deep vein thrombosis (DVT) and pulmonary embolism (PE) due to lack of reported data and the remaining LMWHs were found to be similar in relative efficacy in preventing these outcomes. LIMITATIONS Traditional meta-analysis was not possible for many drug comparisons made within the MTC. Heterogeneity was observed in several of the traditional meta-analyses although this may be an inherent limitation of the studied population. Overall rarity of events contributed to imprecise estimates demonstrated by the wide confidence intervals. CONCLUSIONS Enoxaparin, dalteparin, nadroparin and certoparin are similar in relative efficacy for the prevention of mortality and VTE and in the odds of major or minor bleeding while enoxaparin, nadroparin and certoparin are similar in relative efficacy for the prevention of PE and DVT in hospitalized medical patients.
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Abstract
Venous thromboembolism (VTE) can occur after major general surgery. Pulmonary embolism is recognized as the most common identifiable cause of death in hospitalized patients in the United States. The risk of deep venous thrombosis (DVT) and pulmonary embolism (PE) is higher in colorectal surgical procedures compared with general surgical procedures. The incidence of venous thromboembolism in this population is estimated to be 0.2 to 0.3%. Prevention of VTE is considered a patient-safety measure in most mandated quality initiatives. The measures for prevention of VTE include mechanical methods (graduated compression stockings and intermittent pneumatic compression devices) and pharmacologic agents. A combination of mechanical and pharmacologic methods produces the best results. Patients undergoing surgery should be stratified according to their risk of VTE based on patient risk factors, disease-related risk factors, and procedure-related risk factors. The type of prophylaxis should be commensurate with the risk of VTE based on the composite risk profile.
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Affiliation(s)
- Jonathan Laryea
- Division of Colon and Rectal Surgery, Department of surgery, University of Arkansas for Medical Sciences, Little Rock, Arkansas
| | - Bradley Champagne
- Division of Colon and Rectal Surgery, Department of surgery, Case Western Reserve University, Cleveland, Ohio
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Practical issues with vitamin K antagonists: elevated INRs, low time-in-therapeutic range, and warfarin failure. J Thromb Thrombolysis 2011; 31:249-58. [DOI: 10.1007/s11239-011-0555-z] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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Altman R, Scazziota AS, Pons S, Herrera L, Keller AG, Assefi AR, Di Girolamo G. Effects of enoxaparin preparations on thrombin generation and their correlation with their anti-FXa activity. Curr Med Res Opin 2011; 27:1-9. [PMID: 21083516 DOI: 10.1185/03007995.2010.535512] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
OBJECTIVE Anticoagulant effect of LMWHs is monitored by anti-factor Xa (anti-FXa) activity assay. Since this test has several limitations, the aim of this study was to explore the activity of two LMWHs by thrombin generation assay (TG, which presents an overall picture of hemostatic balance) and its correlation with their anti-FXa activity. METHODS In an open-label, randomized cross-over study, 40 mg of two enoxaparins, the original branded formulation (R) and another one, also marketed in Argentina (T), were daily injected subcutaneously, for 7 days, to 20 healthy volunteers, with a 7-day washout interval. Blood samples were collected before treatment and 180 minutes after the injection on days 3 and 7. TG in platelet-poor plasma activated with tissue factor was assessed by lag time (LT), time to peak (TTP), peak (PTG), and endogenous thrombin potential (ETP). Anti-FXa and anti-FIIa activities, free tissue factor pathway inhibitor (free TFPI), tissue plasminogen activator (t-PA), plasminogen activator inhibitor type 1 (PAI-1), and euglobulin lysis time (ELT) were also assayed. RESULTS The mean (SD) anti-FXa (UI/ml) for T and R increased on days 3 and 7. LT and TTP were significantly prolonged by both LMWHs, with no differences between them. The mean ETP (nmol/L) for T and R at 3 and 7 days after treatment were significantly reduced when compared with basal values (p = 0.001 for all). On day 3, a significant correlation was shown between the variables describing TG and anti-FXa for T and R, without differences between them, for LT (r: 0.516 and 0486), ETP (r: 0.532 and 0.574), PEAK (r: 0.482 and 0.501), and TTP (r: 0.577 and 0.503), respectively. This correlation was also significant on day 7. Anti-FIIa activity and free TFPI increased significantly at 3 and 7 days for both LMWHs, without differences between them. R and T decreased ELT and PAI-1, but had no effect on t-PA. There were no differences between both LMWHs in routine hemostatic tests. No adverse events were reported. CONCLUSIONS Correlation between TG and anti-FXa activity was good. Both enoxaparins induced similar change of coagulation parameters, with a significant increase in fibrinolytic activity.
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Affiliation(s)
- R Altman
- Centro de Trombosis de Buenos Aires, Buenos Aires, Argentina
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Green L, Lawrie AS, Patel S, Hossain F, Chitolie A, Mackie IJ, Haddad FS, Machin SJ. The impact of elective knee/hip replacement surgery and thromboprophylaxis with rivaroxaban or dalteparin on thrombin generation. Br J Haematol 2010; 151:469-76. [DOI: 10.1111/j.1365-2141.2010.08433.x] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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Abstract
The widespread use of central neuraxial block (CNB) and the prevalence of anticoagulation for different indications have led to an inevitable overlap between the two. The most serious complication of CNB in anticoagulated patients is the risk of spinal/epidural haematoma. Performing CNB in these patients is a complex decision that should take into account the twin risks of bleeding and venous/arterial thrombosis if anticoagulation therapies were to be stopped. Various guidelines have been issued to achieve normal haemostasis and thus allow safe administration of CNB. However, the evidence base for many such recommendations is weak, relying mainly on case reports, small studies and pharmacokinetics of the drugs. Given these limitations it is crucial to fully assess individual risk factors and understand anticoagulant pharmacokinetics in order to appropriately set time intervals for catheter insertion/removal. This paper will review traditional and newer anticoagulation/antiplatelet therapies with a view to improving the management of anticoagulated patients undergoing CNB.
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Affiliation(s)
- Laura Green
- Haemostasis Research Unit, Department of Haematology, University College London, London, UK.
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28
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Labarère J, Sevestre MA, Belmin J, Legagneux A, Barrellier MT, Thiel H, Le Roux P, Pernod G, Bosson JL. Low-molecular-weight heparin prophylaxis of deep vein thrombosis for older patients with restricted mobility: propensity analyses of data from two multicentre, cross-sectional studies. Drugs Aging 2009; 26:263-71. [PMID: 19358621 DOI: 10.2165/00002512-200926030-00007] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
Abstract
BACKGROUND Although older patients with restricted mobility are at increased risk for venous thromboembolism, they are under-represented in clinical trials evaluating prophylactic treatments against deep vein thrombosis (DVT). OBJECTIVE To determine whether prolonged prophylaxis with low-molecular-weight heparin (LMWH) is associated with a lower rate of DVT in older patients with restricted mobility. METHODS Two cross-sectional studies were conducted in 50 hospital-based, post-acute care facilities in France in 2001 and 2003. The studies included 1603 evaluable patients aged >or=65 years, including 866 LMWH users (median treatment duration 23 days; interquartile range 13-42) and 737 LMWH non-users. All patients underwent complete compression ultrasonography performed by board-certified vascular medicine physicians. The primary study outcome was proximal DVT. Propensity analyses were used to control for bias in LMWH treatment assignment. RESULTS The rate of proximal DVT was 4% (35/866) and 5.7% (42/737) for LMWH users and non-users, respectively (p = 0.16). Prophylaxis with LMWH was associated with decreased odds of proximal DVT after adjusting for baseline characteristics (odds ratio [OR] 0.56; 95% CI 0.33, 0.95; p = 0.03) or quintile of propensity score (OR 0.58; 95% CI 0.35, 0.99; p = 0.04). In propensity matched analysis, 342 LMWH users were at decreased odds of proximal DVT compared with 342 non-users (OR 0.50; 95% CI 0.24, 1.00; p = 0.04). The decrease in proximal DVT was paralleled by a similar decrease in distal DVT. Compared with non-users, only high-risk dose users had decreased odds of DVT. CONCLUSIONS In this observational study, prophylaxis with a high-risk dose of LMWH was associated with decreased odds of proximal DVT in older patients with restricted mobility. Further study is needed before recommending routine prophylaxis with LMWH in these patients.
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Affiliation(s)
- José Labarère
- Quality of Care Unit, Grenoble University Hospital, Grenoble, France.
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Patel RP, Narkowicz C, Jacobson GA. Investigation of freezing- and thawing-induced biological, chemical, and physical changes to enoxaparin solution. J Pharm Sci 2009; 98:1118-28. [PMID: 18661541 DOI: 10.1002/jps.21483] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
This study investigated the effect of freezing and thawing on the biological, physical, and chemical properties of enoxaparin solution. Solutions were frozen and thawed under different conditions, in the presence or absence of dimethyl sulfoxide (DMSO) or 1,2-propanediol (1,2-PD), and the antifactor Xa (AFXa) activity was determined. Enoxaparin solution lost more than 60% of its AFXa activity when thawed rapidly after freezing at -196 degrees C. The loss of AFXa activity was less with higher freezing temperatures and increased with the number of freeze/thaw cycles, but was independent of the duration of freezing. Slow freezing to -196 degrees C with rapid thawing, or rapid freezing with slow thawing, resulted in negligible loss of AFXa activity. The loss of AFXa activity did not involve the loss of N-sulfate groups, the breakdown of glycosidic bonds or the glassy state transition. Controlling the freezing or thawing conditions, dilution with water or addition of a small percentage of DMSO ameliorated the loss of enoxaparin AFXa activity. The loss in AFXa activity was found by size exclusion chromatography to be primarily due to aggregation and was reversed by sonication in the presence of DMSO. These results may provide insight into solutions for the long-term storage of concentrated or diluted enoxaparin.
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Affiliation(s)
- Rahul P Patel
- School of Pharmacy, University of Tasmania, Private Bag 26, Hobart, Tasmania 7001, Australia.
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Effective reversed-phase ion pair high-performance liquid chromatography method for the separation and characterization of intact low-molecular-weight heparins. Anal Biochem 2009; 387:113-21. [DOI: 10.1016/j.ab.2009.01.007] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2008] [Revised: 01/01/2009] [Accepted: 01/04/2009] [Indexed: 11/21/2022]
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31
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Llau JV, Sapena ML, López Forte C, Ferrandis R. [Anaesthesia and thromboembolic disease]. Med Clin (Barc) 2009; 131 Suppl 2:42-7. [PMID: 19087850 DOI: 10.1016/s0025-7753(08)76448-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
Abstract
Currently, pharmacological thromboprophylaxis is frequently required in patients undergoing surgery, due to the high risk of deep venous thrombosis in the perioperative period. The administration of these anticoagulant agents (in Spain, usually low molecular weight heparins or fondaparinux, and in future, probably also the new oral anticoagulants dabigatran and rivaroxaban) may conflict with regional anesthetic techniques, in which maintaining hemostatic integrity is essential. Therefore, safety protocols have been designed that allow thromboprophylaxis to be administered with optimal effectiveness and anesthetic techniques to be performed with maximal safety; these protocols are based on the drug used, as well as on the dose and time of administration. The present chapter reviews the details related to these issues.
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Affiliation(s)
- Juan V Llau
- Servicio de Anestesiología y Reanimación, Hospital Clínic Univesitari de València, Valencia, España.
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32
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McCullagh L, Tilson L, Walsh C, Barry M. A cost-effectiveness model comparing rivaroxaban and dabigatran etexilate with enoxaparin sodium as thromboprophylaxis after total hip and total knee replacement in the irish healthcare setting. PHARMACOECONOMICS 2009; 27:829-846. [PMID: 19803538 DOI: 10.2165/11313800-000000000-00000] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
BACKGROUND It has been estimated that major orthopaedic surgery has the highest risk of venous thromboembolism (deep vein thrombosis and pulmonary embolism) when compared with other surgery. Two new orally active anticoagulants have recently become licensed in Ireland for the primary prevention of venous thromboembolism in adult patients undergoing elective total hip replacement (THR) or total knee replacement (TKR). Rivaroxaban (Xarelto) is a direct factor Xa inhibitor and dabigatran etexilate (Pradaxa) is a prodrug of the active compound dabigatran, which inhibits thrombin. OBJECTIVE To evaluate the cost effectiveness of rivaroxaban and dabigatran etexilate compared with enoxaparin sodium for the prophylaxis of venous thromboembolism in patients undergoing elective THR and TKR in the Irish healthcare setting. METHODS The evaluation was conducted from the Irish health-payer perspective. A static decision-tree model was developed with a 180-day post-surgery time horizon. Separate models for the disease states THR and TKR were run to accommodate the different venous thromboembolism risks associated with each procedure. Outcome measures were QALYs and life-years gained (LYG). Costs were valued in euro, year 2008 values. One-way sensitivity analysis of all probabilities in the model was performed. A probabilistic sensitivity analysis using second-order Monte Carlo simulation was performed to determine the probability of cost effectiveness at euro 45,000 per QALY threshold. RESULTS In the THR base-case model, rivaroxaban dominated both dabigatran etexilate and enoxaparin sodium. The incremental cost-effectiveness ratios for dabigatran etexilate relative to enoxaparin were euro 23,934 per LYG and euro 17,835 per QALY. In the TKR base-case model, rivaroxaban dominated both dabigatran etexilate and enoxaparin sodium. Dabigatran etexilate also dominated enoxaparin sodium. In the one-way sensitivity analysis, the THR model was robust to all but four probability variations; the TKR model was robust to all variations. At a cost-effectiveness threshold of euro 45,000 per QALY, the probability that rivaroxaban was the most cost-effective strategy after THR was 39%, followed by dabigatran etexilate at 32% and enoxaparin sodium at 29%. The probability that rivaroxaban was the most cost-effective strategy after TKR was 46%, followed by dabigatran etexilate at 30% and enoxaparin sodium at 24%. CONCLUSION Base-case analysis indicates that when both rivaroxaban and dabigatran etexilate are compared with enoxaparin sodium, rivaroxaban is the less costly and more effective option after THR and TKR. Probabilistic sensitivity analysis indicates that rivaroxaban is the most cost-effective strategy at a cost-effectiveness threshold of euro 45,000 per QALY; however, there is uncertainty regarding this strategy being more cost effective than dabigatran etexilate when both are compared with enoxaparin sodium.
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Affiliation(s)
- Laura McCullagh
- National Centre for Pharmacoeconomics, St James's Hospital, Dublin, Ireland.
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33
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Netti GS, Margaglione M, Gesualdo L. How to handle low-molecular-weight heparins in patients with decreased renal function: an open issue. Intern Emerg Med 2008; 3:307-9. [PMID: 18807147 DOI: 10.1007/s11739-008-0195-2] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/31/2008] [Accepted: 09/01/2008] [Indexed: 10/21/2022]
Affiliation(s)
- Giuseppe Stefano Netti
- Department of Biomedical Sciences, Section of Nephrology, University of Foggia, Foggia, Italy
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34
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Cunningham MS, Preston RJS, O'Donnell JS. Does antithrombotic therapy improve survival in cancer patients? Blood Rev 2008; 23:129-35. [PMID: 19046797 DOI: 10.1016/j.blre.2008.10.002] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Venous thromboembolism (VTE) is a common complication of malignancy, and is associated with significant morbidity and mortality. Anticoagulant therapy, in the form of heparin and warfarin, plays an important role in the prevention of recurrent VTE. Recent studies have demonstrated that long-term therapy with low molecular weight heparin (LMWH) is more effective than warfarin in patients with cancer. In addition, accumulating clinical evidence suggests that LMWH significantly improves overall survival in cancer patients without VTE. Intriguingly, however, this improved survival cannot simply be explained by a reduction in fatal pulmonary embolism. Furthermore, the beneficial effects persist long after the LMWH has been discontinued, suggesting that LMWH can directly influence tumour cell biology. This hypothesis is entirely plausible, given the complex feedback mechanisms that exist between tumour cells, coagulation proteases, and vascular endothelial cells. Furthermore, an accumulating body of in vitro experimental evidence suggests that both heparin and warfarin have direct antineoplastic effects. Further large randomized controlled trials will be required in order to validate these exciting preliminary data, and to define whether anticoagulant therapy may constitute a useful adjunctive therapy in the management of cancer patients without VTE.
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Affiliation(s)
- Moya S Cunningham
- Academic Unit of Clinical and Molecular Oncology, Institute of Molecular Medicine, Trinity College Dublin, Ireland
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35
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Fareed J, Jeske W, Fareed D, Clark M, Wahi R, Adiguzel C, Hoppensteadt D. Are all low molecular weight heparins equivalent in the management of venous thromboembolism? Clin Appl Thromb Hemost 2008; 14:385-92. [PMID: 18815137 DOI: 10.1177/1076029608319881] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
Low molecular weight heparins are replacing unfractionated heparin in a number of clinical indications because of their improved subcutaneous bioavailability and more predictable antithrombotic response. Clinical trials have demonstrated that low molecular weight heparins are at least as safe and effective as unfractionated heparin for the initial treatment of venous thromboembolism, and unfractionated heparin and warfarin for primary and secondary thromboprophylaxis. The mechanism behind the antithrombotic action of low molecular weight heparins is not fully understood but is likely to involve inhibition of coagulation factors Xa and IIa (thrombin), release of tissue-factor-pathway inhibitor, and inhibition of thrombin activatable fibrinolytic inhibitor. Different low molecular weight heparins have been shown to have various effects on coagulation parameters. Seven low molecular weight heparins are currently marketed worldwide, each demonstrated distinct chemical entities with unique pharmacokinetic and pharmacodynamic profiles. Each low molecular weight heparin is approved for specific indications based on the available efficacy and safety data for that product. The relative efficacy and safety of the low molecular weight heparins are unclear because there have been very few direct comparisons in randomized clinical trials. While recommending low molecular weight heparins for the prevention and treatment of venous thromboembolism, clinical guidelines have not specified individual agents. National and international organizations recognize that low molecular weight heparins are distinct entities and that they should not be used interchangeably in clinical practice. Each low molecular weight heparin should be used at the recommended dose when efficacy and safety data exist for the condition being treated. When these data are not available, the dosing and administration of low molecular weight heparins must be adapted from existing data and recommendations.
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Affiliation(s)
- Jawed Fareed
- Loyola University Medical Center, 2160 S. First Avenue, Maywood, IL 60153, USA.
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36
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Efficacy and safety of once daily low molecular weight heparin (tinzaparin sodium) in high risk pregnancy. Blood Coagul Fibrinolysis 2008; 19:689-92. [DOI: 10.1097/mbc.0b013e32830b14ef] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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37
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Abstract
The use of low molecular weight heparins (LMWH) in obstetric care has grown considerably since their introduction into clinical practice in the early 1990s. However, because of the physiological changes of pregnancy, the predictable pharmacokinetic profile of LMWH is lost and some uncertainty exists around the optimal dosing regimen for LMWH in obstetric care. Two recent United Kingdom prospective surveys of the management of acute venous thromboembolism (VTE) suggest that despite recommendations from the Royal College of Obstetricians and Gynaecologists (RCOG) for a twice daily LMWH regimen, a once daily regimen is acceptable for the treatment of venous thromboembolism; and that accepted thromboprophylactic doses licensed for non-pregnant individuals may not be applicable during the second and third trimester for VTE thromboprophylaxis. Accepting that randomized clinical studies are difficult in obstetric care, future advances could be made through population-based multi-center studies, coupled with pharmacokinetic modeling studies, which have the potential to determine the optimal dosing regimen for the various obstetric indications.
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Affiliation(s)
- J P Patel
- Department of Pharmacy, School of Biomedical and Health Sciences, King's College London, London, UK
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38
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Cunningham MS, Gilmore R, O’Donnell D, O’Donnell JS. Management of refractory venous thrombosis associated with malignancy using a supra-therapeutic enoxaparin regimen. Ir J Med Sci 2008; 178:339-41. [DOI: 10.1007/s11845-008-0200-9] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2008] [Accepted: 07/14/2008] [Indexed: 11/29/2022]
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39
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Kuczka K, Harder S, Picard-Willems B, Warnke A, Donath F, Bianchini P, Parma B, Blume H. Biomarkers and coagulation tests for assessing the biosimilarity of a generic low-molecular-weight heparin: results of a study in healthy subjects with enoxaparin. J Clin Pharmacol 2008; 48:1189-96. [PMID: 18716314 DOI: 10.1177/0091270008322911] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Low-molecular-weight heparins (LMWHs) differ considerably in their influence on clotting tests and release of tissue factor pathway inhibitor (TFPI). Biosimilarity therefore becomes an issue when generic forms of LMWHs are developed. So far, no bioequivalence study with a generic LMWH has been reported. A generic enoxaparin (test) was compared with the originator (reference) in 20 volunteers after single-dose subcutaneous administration (40 mg enoxaparin sodium, 4000 IU/mL anti-factor Xa (anti-FXa; activity). Target variables were anti-FXa and anti-FIIa activity, activated partial thromboplastin time (aPTT), prothrombinase-induced clotting time (PiCT), and TFPI over 24 hours. The statistical evaluation of the anti-FXa activity profile demonstrated bioequivalence of test and reference with confidence intervals of area under the plasma concentration-time curve (AUC0-tlast) (93%-99%) and Amax (88%-95%). Confidence intervals of AUC(0-tlast) (89%-102%) and Amax (90%-103%) of anti-FIIa activity also fulfill bioequivalence criteria. The 90% confidence interval for the maximum concentration of TFPI ranged from 90% to 113%. The claim of similarity was also supported by aPTT and PiCT profiles. Bioequivalence with the originator enoxaparin could be demonstrated by ex vivo inhibition of FXa and FIIa activity, by coagulation tests (aPTT and PiCT), and by in vivo release of TFPI. Whether such data also prove biosimilarity of the generic enoxaparin needs to be determined.
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Affiliation(s)
- Karina Kuczka
- Pharmazentrum frankfurt/ZAFES, Institute for Clinical Pharmacology, University Hospital Frankfurt, Germany
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40
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41
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Voke J, Keidan J, Pavord S, Spencer NH, Hunt BJ. The management of antenatal venous thromboembolism in the UK and Ireland: a prospective multicentre observational survey. Br J Haematol 2007; 139:545-58. [DOI: 10.1111/j.1365-2141.2007.06826.x] [Citation(s) in RCA: 71] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
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42
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Wang ZM, Li L, Zheng BS, Normakhamatov N, Guo SY. Preparation and anticoagulation activity of sodium cellulose sulfate. Int J Biol Macromol 2007; 41:376-82. [PMID: 17602735 DOI: 10.1016/j.ijbiomac.2007.05.007] [Citation(s) in RCA: 59] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2007] [Revised: 05/11/2007] [Accepted: 05/14/2007] [Indexed: 10/23/2022]
Abstract
Semi-synthesis of cellulose sulfate sodium (Na-MCS) was carried out by sulfation of microcrystalline cellulose (MCC) with chlorosulfonic acid-dimethylformamide complex as sulfating agent. As shown by FT-IR, NMR spectroscopy, and elemental analysis, the sulfation occurred mainly at C6, partially at C2, and no substitution at C3. The substitution degree ranged from 1.10 to 1.70 and the average molecular weight is between 1.1 and 3.5 x 10(4)Da. The anticoagulant efficacy and its possible mechanism were investigated using in vitro, in vivo coagulation assays and amidolytic tests in comparison with heparin. Results indicated that Na-MCS exhibited higher anticoagulation activity based on activated partial thromboplastin time (APTT) assay and prolonged the thrombin time (TT) to a lesser extent than heparin. No effect was detected on the prothrombin time (PT). Subcutaneous administration of Na-MCS to mice increased the clotting time (CT) in a moderate dose-dependent manner with a longer duration. Na-MCS exhibited anticoagulation activity mainly by accelerating the inhibition of antithrombin III (AT-III) on coagulation factors FIIa and FXa in plasma.
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Affiliation(s)
- Zhao Mei Wang
- Research Institute of Light Industry and Chemical Engineering, South China University of Technology, Guangzhou 510640, PR China.
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43
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Einstein MH, Pritts EA, Hartenbach EM. Venous thromboembolism prevention in gynecologic cancer surgery: A systematic review. Gynecol Oncol 2007; 105:813-9. [PMID: 17449089 DOI: 10.1016/j.ygyno.2007.03.004] [Citation(s) in RCA: 80] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2006] [Revised: 02/27/2007] [Accepted: 03/08/2007] [Indexed: 11/21/2022]
Abstract
OBJECTIVES Advanced age, pelvic surgery, and the presence of malignancy place gynecologic oncology patients at high risk for venous thromboembolism (VTE). This study was designed to systematically analyze the world's literature on VTE in these patients and determine the optimal prophylaxis regimen. METHODS Computerized searches of Pubmed, Ovid, DARE, ACP Journal Club, Cochrane Database of Systematic Reviews, and Cochrane Controlled Trials Registry 1966-2005 were performed, as well as EMBASE 1980-2005. Major conferences and target references were hand-searched. Inclusion criteria were randomized controlled trials (RCTs) evaluating VTE prophylaxis with heparin, low-molecular-weight heparin (LMWH), and sequential compression devices (SCD). The search yielded 278 articles; 11 met inclusion criteria. Data were abstracted by one author and analyzed with the Mantel-Haenszel method. RESULTS The analysis of heparin-versus-control revealed a significant decrease in DVT in patients receiving heparin (RR=0.58, 95% CI 0.35-0.95). There were no significant differences in EBL or transfusions between the two groups. In the 320 patients in the heparin vs. LMWH studies, there was no significant difference in DVT (RR 0.91, 95% CI 0.38-2.17), although power analysis demonstrated insufficient numbers to show a difference. No patient in either group required re-exploration for bleeding. CONCLUSIONS All gynecologic cancer patients should receive VTE prophylaxis. Although heparin, LMWH, and SCD have been shown to be safe and effective, due to the paucity of data in the gynecologic oncology literature, no one prevention modality can be considered superior at this time. Adequately powered RCTs are urgently needed to determine the optimal regimen in these high-risk patients.
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Affiliation(s)
- M Heather Einstein
- Department of Obstetrics and Gynecology, University of Wisconsin Hospital and Clinics, Madison, WI 53792, USA.
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Berges A, Laporte S, Epinat M, Zufferey P, Alamartine E, Tranchand B, Decousus H, Mismetti P. Anti-factor Xa activity of enoxaparin administered at prophylactic dosage to patients over 75 years old. Br J Clin Pharmacol 2007; 64:428-38. [PMID: 17509040 PMCID: PMC2048556 DOI: 10.1111/j.1365-2125.2007.02920.x] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022] Open
Abstract
AIMS Major bleeding complications with low-molecular-weight heparin (LMWH) treatment have been reported both in clinical studies and during postmarketing surveillance. Monitoring of antifactor Xa (anti-Xa) activities is therefore recommended in special populations often predisposed to renal impairment. The PROPHRE.75 study was conducted to estimate the distribution parameters of anti-Xa activity in the elderly. METHODS PROPHRE.75 was a prospective study of a cohort of consecutive patients aged >75 years and treated with 4000 IU of enoxaparin once daily for venous thromboembolism prophylaxis. Dosing history and measurements of anti-Xa activity in sparse samples were recorded throughout treatment. The covariates included weight, gender, age, renal function, medical history and concomitant medication. Population parameters and interindividual variability were estimated using NONMEM V software. RESULTS Anti-Xa activity was studied in 189 patients (mean age 82 +/- 5 years, 22% weighing <50 kg, 50% presenting renal impairment according to the Cockcroft and Gault formula). A first-order input two-compartment model best fitted the data. Clearance was significantly related to body weight and creatinine clearance based on the simplified Modification of Diet in Renal Disease formula, central volume being related to body weight. According to individual Bayesian estimations, 4% of patients presented with a peak anti-Xa activity >1.0 IU ml(-1), but this group did not include the sole patient experiencing a major bleed (0.53%). CONCLUSIONS Systematic monitoring of anti-Xa activity in elderly patients treated with enoxaparin at prophylactic doses does not seem to be necessary to prevent the occurrence of major bleeding.
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Affiliation(s)
- A Berges
- Clinical Pharmacology Department, Thrombosis Research Group (EA3065), University Hospital of Saint-Etienne, Saint-Etienne, France
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Llau JV, De Andrés J, Gomar C, Gómez-Luque A, Hidalgo F, Torres LM. Anticlotting drugs and regional anaesthetic and analgesic techniques. Eur J Anaesthesiol 2007; 24:387-98. [PMID: 17207294 DOI: 10.1017/s0265021506001918] [Citation(s) in RCA: 49] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
The wide use of anticlotting drugs by patients scheduled for surgery is a challenge for the anaesthesiologist when considering a regional anaesthesia technique. This practice seems safe if there is an appropriate management based on safety intervals established according to the pharmacology of the drug and the regional technique. Some anaesthesiology societies have published recommendations for the safe practice of regional anaesthesia with the simultaneous use of anticoagulants (heparin, low molecular weight heparins, oral anticoagulants (OA), fondaparinux and others) and antiplatelet agents (aspirin, clopidogrel, ticlopidine, argatroban and others). One of the most recent guidelines has been published by the Spanish Society of Anaesthesia and Critical Care. This article reviews these recommendations and compares them with others published in the last years. The recommendations are similar, but some interesting differences can be observed and need to be considered. A European consensus in this setting would probably be necessary.
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Affiliation(s)
- J V Llau
- Hospital Clinico Universitario, Department of Anaesthesiology, Critical Care and Pain Therapy, Valencia, Spain.
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46
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Affiliation(s)
- A Tosetto
- Hematology Department, S. Bortolo Hospital, Vicenza, Italy.
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47
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Samama MM, Kleber FX. An update on prevention of venous thromboembolism in hospitalized acutely ill medical patients. Thromb J 2006; 4:8. [PMID: 16817957 PMCID: PMC1550384 DOI: 10.1186/1477-9560-4-8] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2005] [Accepted: 07/03/2006] [Indexed: 11/13/2022] Open
Abstract
Both the recently updated consensus guidelines published by the American College of Chest Physicians, and the International Union of Angiology recommend thromboprophylaxis with either low-molecular-weight heparin (LMWH) or unfractionated heparin (UFH) in medical patients at risk of VTE. However, no guidance is given regarding the appropriate dosing regimens that should be used for thromboprophylaxis in this patient group. LMWH (enoxaparin and dalteparin) and UFH have been shown to be effective for thromboprophylaxis in at-risk hospitalized medical patients. Although LMWH once daily (o.d.) has been shown to be as effective as UFH three times daily (t.i.d.) for thromboprophylaxis in at-risk medical patients, there are no data to show that UFH twice daily (b.i.d) is as effective as either LMWH o.d. or UFH t.i.d. On the basis of currently available evidence, the LMWHs enoxaparin and dalteparin are more attractive alternatives to UFH for the prevention of VTE in hospitalized medical patients because of their convenient once-daily administration and better safety profile, demonstrated in terms of reduced bleeding, HIT, and other adverse events.
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Affiliation(s)
| | - Franz-Xaver Kleber
- Charité Medical School, Unfallkrankenhaus Berlin Academic Teaching Hospital, Berlin, Germany
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Tran H, McRae S, Ginsberg J. Anticoagulant Treatment of Deep Vein Thrombosis and Pulmonary Embolism. Clin Geriatr Med 2006; 22:113-34, ix. [PMID: 16377470 DOI: 10.1016/j.cger.2005.09.004] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Venous thrombosis is a common disease. As the mean age of the population increases, so does the incidence of venous thromboembolism. Anticoagulant therapy is equally effective in young and older patients, and can reduce substantially the associated morbidity and mortality. When considering long-term oral anticoagulant therapy in older patients, however, careful ongoing evaluation is imperative to ensure that the risk of bleeding does not outweigh the antithrombotic benefits.
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Affiliation(s)
- Huyen Tran
- Department of Medicine, McMaster University Medical Centre, Hamilton, Ontario L8N 3Z5, Canada
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Al Dieri R, Alban S, Béguin S, Hemker HC. Fixed dosage of low-molecular-weight heparins causes large individual variation in coagulability, only partly correlated to body weight. J Thromb Haemost 2006; 4:83-9. [PMID: 16409456 DOI: 10.1111/j.1538-7836.2005.01672.x] [Citation(s) in RCA: 48] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
BACKGROUND Low-molecular-weight heparins (LMWHs) are routinely given without the control of their effect on coagulation. The endogenous thrombin potential (ETP) is a sensitive detector of the heparin effect. QUESTION What is the interindividual variation in TG after a fixed dose of LMWH in normal volunteers, is it explained by variation in weight? METHODS Subcutaneous (s.c.) injection, in 12 healthy volunteers, of 9000 aXa-units of unfractionated heparin (UFH) and of three heparins with narrow MW distribution around 10.5, 6.0 and 4.5 kD. Measurement of anti-thrombin (aIIa) and antifactor Xa (aXa)-activities and ETP at 11 time points over 24 h. RESULTS The coefficient of variation (CV) of the AUCs of aXa- and aIIa-activities is 50% for UFH and 22-37% for LMWHs. Because of the hyperbolic form of the dose-response curve, the CV of the inhibition of the ETP is lower: 32% for UFH and 13-21% for the LMWHs. Fixed dosage of LMWH caused under-dosage in 10-13% of the samples and over-dosage in 5-11%. High or low response is an individual property independent of the type of heparin injected and only partially explained by variation in body weight. CONCLUSION Optimized individual dosage of LMWH is possible through recognition of high and low responders, which requires one measurement of the heparin concentration or, preferably, the heparin effect on the ETP, 2-5 h after a first injection.
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Affiliation(s)
- R Al Dieri
- Synapse BV, Cardiovascular Research Institute, Maastricht, The Netherlands.
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Cheer SM, Dunn CJ, Foster R. Tinzaparin sodium: a review of its pharmacology and clinical use in the prophylaxis and treatment of thromboembolic disease. Drugs 2004; 64:1479-502. [PMID: 15212562 DOI: 10.2165/00003495-200464130-00006] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
Abstract
Tinzaparin sodium (tinzaparin; innohep) is a low molecular weight heparin (LMWH) formed by the enzymatic degradation of porcine unfractionated heparin (UFH). In clinical trials, once-daily subcutaneous (SC) tinzaparin was effective and generally well tolerated in the prophylaxis and treatment of thromboembolic disease. SC tinzaparin 75 anti-Xa IU/kg/day showed similar thromboprophylactic efficacy to adjusted-dosage oral warfarin in patients undergoing total hip arthroplasty; in patients undergoing knee replacement, the incidence of deep vein thrombosis (DVT) was significantly lower with tinzaparin. The drug had similar efficacy to equivalent-dosage SC enoxaparin sodium in orthopaedic surgery. In patients undergoing general surgery, SC tinzaparin 3500 anti-Xa IU/day was of equivalent thromboprophylactic efficacy to SC UFH 5000IU twice daily. Encouraging preliminary results have been obtained with tinzaparin in the prevention of DVT in patients with complete motor paralysis. In the initial treatment of acute proximal DVT and pulmonary embolism, SC tinzaparin 175 anti-Xa IU/kg/day was at least as effective as adjusted-dosage intravenous (IV) UFH. In the outpatient treatment of venous thromboembolism, tinzaparin has demonstrated similar efficacy to dalteparin sodium (dalteparin) and warfarin. Tinzaparin was effective in preventing clotting in haemodialysis circuits; the anticoagulant efficacy of tinzaparin in patients undergoing haemodialysis was similar to that of SC dalteparin and similar to or less than (although in this case the tinzaparin dose was too low for sufficient anticoagulant efficacy) that of IV UFH. Advantages of tinzaparin over UFH and warfarin include ease of administration and lack of need for laboratory monitoring. Tinzaparin is more cost effective than UFH in the treatment of established thromboembolic disease, and home-based treatment with tinzaparin may offer greater cost benefits than hospital-based therapy. Tinzaparin is well tolerated, including in elderly patients and those with renal impairment receiving long-term treatment. Incidences of major bleeding complications were low and reports of heparin-induced thrombocytopenia were infrequent in clinical studies. In conclusion, tinzaparin is a valuable LMWH in the prophylaxis and management of thromboembolic disease.
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Affiliation(s)
- Susan M Cheer
- Adis International Limited, 41 Centorian Drive, Private Bag 65901, Mairangi Bay, Auckland 1311, New Zealand.
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