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Abstract
Viscoelastic testing methods examine the real-time formation of a clot in a whole blood sample, and include thromboelastography (TEG), rotational thromboelastometry (ROTEM), and several other testing platforms. They allow for concurrent assessment of multiple aspects of clotting, including plasmatic coagulation factors, platelets, fibrinogen, and the fibrinolytic pathway. This testing is rapid and may be performed at the point-of-care, allowing for prompt identification of coagulopathies to guide focused and rational administration of blood products as well as the identification of anticoagulant effect. With recent industry progression towards user-friendly, cartridge-based, portable instruments, viscoelastic testing has emerged in the 21st century as a powerful tool to guide blood transfusions in the bleeding patient, and to identify and treat both bleeding and thrombotic conditions in many operative settings, including trauma surgery, liver transplant surgery, cardiac surgery, and obstetrics. In these settings, the use of transfusion algorithms guided by viscoelastic testing data has resulted in widespread improvements in patient blood management as well as modest improvements in select patient outcomes. To address the increasingly wide adoption of viscoelastic methods and the growing number of medical and laboratory personnel tasked with implementing, performing, and interpreting these methods, this chapter provides an overview of the history, physiology, and technology behind viscoelastic testing, as well as a practical review of its clinical utility and current evidence supporting its use. Also included is a review of testing limitations and the contextual role played by viscoelastic methods among all coagulation laboratory testing.
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Affiliation(s)
- Timothy Carll
- Department of Pathology, University of Chicago, Chicago, IL, United States.
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2
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Wool GD, Carll T. Viscoelastic testing: Critical appraisal of new methodologies and current literature. Int J Lab Hematol 2023; 45:643-658. [PMID: 37559473 DOI: 10.1111/ijlh.14144] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2023] [Accepted: 07/25/2023] [Indexed: 08/11/2023]
Abstract
United States Food and Drug Administration (FDA)-approved viscoelastic testing (VET) methodologies have significantly changed in the last 10 years, with the availability of cartridge-based VET. Some of these cartridge-based methodologies use harmonic resonance-based clot detection. While VET has always allowed for the evaluation of real-time clot formation, cartridge-based VET provides increased ease of use as well as greater portability and robustness of results in out-of-laboratory environments. Here we review the use of VET in a variety of clinical contexts, including cardiac surgery, trauma, liver transplant, obstetrics, and hypercoagulable states such as COVID-19. As of now, high quality randomized trial evidence for new generation VET (TEG 6s, HemoSonics Quantra, ROTEM sigma) is limited. Nevertheless, the use of VET-guided transfusion algorithms appears to result in reduced blood usage without worsening of patient outcomes. Future work comparing the new generation VET instruments and continuing to validate clinically important cut-offs will help move the field of point-of-care coagulation monitoring forward and increase the quality of transfusion management in bleeding patients.
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Affiliation(s)
- Geoffrey D Wool
- Department of Pathology, University of Chicago, Chicago, Illinois, USA
| | - Timothy Carll
- Department of Pathology, University of Chicago, Chicago, Illinois, USA
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Ramanujam V, DiMaria S, Varma V. Thromboelastography in the Perioperative Period: A Literature Review. Cureus 2023; 15:e39407. [PMID: 37362492 PMCID: PMC10287184 DOI: 10.7759/cureus.39407] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 05/23/2023] [Indexed: 06/28/2023] Open
Abstract
Assessing coagulation status is essential for prompt intervention to reduce morbidity and mortality related to bleeding and thrombotic complications during the perioperative period. Traditional coagulation tests such as platelet count, activated partial thromboplastin time (aPTT), prothrombin time (PT), international normalized ratio (INR), and activated clotting time (ACT) provide only static evaluation. These tests are not designed for assessment of dynamically changing coagulation conditions during the perioperative time. However, viscoelastic coagulation testing such as thromboelastography (TEG) produces a rapid numerical and graphical representation that helps to detect and direct targeted hemostatic therapy. Searching the literature through PubMed, Medline, Ovid, CINAHL, and ClinicalTrials.gov we retrieved 210 studies, which represent the use of TEG in the perioperative period. The included studies were categorized under various settings such as trauma, obstetrics, orthopedics, intensive care unit (ICU), cardiovascular, transplant, and miscellaneous scenarios. TEG showed promising results in trauma surgeries in predicting mortality, hypercoagulability, and bleeding even when it was compared to conventional methods. TEG was also useful in monitoring anticoagulant therapy in orthopedic and obstetric surgeries; however, its role in predicting thrombotic events, hypercoagulability, or complications was questionable. In ICU patients, it showed promising results, especially in the prediction or improvement of sepsis, coagulopathy, thrombotic events, ICU duration, hospital stay, and ventilator duration. TEG parameters effectively predicted hypercoagulation in transplant surgeries. Regarding cardiovascular surgeries, they were effective in the prediction of the need for blood products, coagulopathy, thrombotic events, and monitoring anticoagulation therapy. More randomized clinical trials comparing TEG parameters with standardized tools are needed to produce robust results to standardize its use in different perioperative settings.
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Affiliation(s)
- Vendhan Ramanujam
- Department of Anesthesiology, Rhode Island Hospital/The Warren Alpert Medical School of Brown University, Providence, USA
| | - Stephen DiMaria
- Department of Anesthesiology, Rhode Island Hospital/The Warren Alpert Medical School of Brown University, Providence, USA
| | - Vivek Varma
- Department of Anesthesiology, Rhode Island Hospital/The Warren Alpert Medical School of Brown University, Providence, USA
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Twine CP, Kakkos SK, Aboyans V, Baumgartner I, Behrendt CA, Bellmunt-Montoya S, Jilma B, Nordanstig J, Saratzis A, Reekers JA, Zlatanovic P, Antoniou GA, de Borst GJ, Bastos Gonçalves F, Chakfé N, Coscas R, Dias NV, Hinchliffe RJ, Kolh P, Lindholt JS, Mees BME, Resch TA, Trimarchi S, Tulamo R, Vermassen FEG, Wanhainen A, Koncar I, Fitridge R, Matsagkas M, Valgimigli M. Editor's Choice - European Society for Vascular Surgery (ESVS) 2023 Clinical Practice Guidelines on Antithrombotic Therapy for Vascular Diseases. Eur J Vasc Endovasc Surg 2023; 65:627-689. [PMID: 37019274 DOI: 10.1016/j.ejvs.2023.03.042] [Citation(s) in RCA: 36] [Impact Index Per Article: 36.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2023] [Accepted: 03/03/2023] [Indexed: 04/05/2023]
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Kim Y, Patel SS, McElroy IE, DeCarlo C, Bellomo TR, Majumdar M, Lella SK, Mohebali J, Dua A. A Systematic Review of Thromboelastography Utilization in Vascular and Endovascular Surgery. J Vasc Surg 2021; 75:1107-1115. [PMID: 34788649 DOI: 10.1016/j.jvs.2021.11.037] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2021] [Accepted: 11/08/2021] [Indexed: 01/30/2023]
Abstract
OBJECTIVE Thromboelastography (TEG) is diagnostic modality that analyzes real-time blood coagulation parameters. Clinically, TEG primarily allows for directed blood component resuscitation among patients with acute blood loss and coagulopathy. The utilization of TEG has been widely adopted in among other surgical specialties; however, its use in vascular surgery is less prominent. We aimed to provide an up-to-date review of TEG utilization in vascular and endovascular surgery. METHODS Using PRISMA guidelines, a literature review with the Medical Subject Headings (MeSH) terms "TEG and arterial events", "TEG and vascular surgery", "TEG and vascular", "TEG and endovascular surgery", "TEG and endovascular", "TEG and peripheral artery disease", "TEG and prediction of arterial events", "TEG and prediction of complications ", "TEG and prediction of thrombosis", "TEG and prediction of amputation", and "TEG and amputation" was performed in Cochrane and PubMed databases to identify all peer-reviewed studies of TEG utilization in vascular surgery, written between 2000-2021 in the English language. The free text and MeSH subheadings search terms included diagnosis, complications, physiopathology, surgery, mortality, and therapy to further restrict the articles. Studies were excluded if they were not in humans or pertaining to vascular or endovascular surgery. Additionally, case reports and studies with limited information regarding TEG utilization were excluded. Each study was independently reviewed by two researchers to assess for eligibility. RESULTS Of the 262 studies identified through the MeSH strategy, 15 studies met inclusion criteria and were reviewed and summarized. Literature on TEG utilization in vascular surgery spanned cerebrovascular disease (n=3), peripheral arterial disease (n=3), arteriovenous malformations (n=1), venous thromboembolic events (n=7), and perioperative bleeding and transfusion (n=1). In cerebrovascular disease, TEG may predict the presence and stability of carotid plaques, analyze platelet function before carotid stenting, and compare efficacy of antiplatelet therapy after stent deployment. In peripheral arterial disease, TEG has been used to predict disease severity and analyze the impact of contrast on coagulation parameters. In venous disease, TEG may predict hypercoagulability and thromboembolic events among various patient populations. Finally, TEG can be utilized in the postoperative setting to predict hemorrhage and transfusion requirements. CONCLUSIONS This systematic review provides an up-to-date summarization of TEG utilization in multiple facets of vascular and endovascular surgery.
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Affiliation(s)
- Young Kim
- Division of Vascular and Endovascular Surgery Harvard Medical School, Massachusetts General Hospital Boston, MA
| | - Shiv S Patel
- Division of Vascular and Endovascular Surgery Harvard Medical School, Massachusetts General Hospital Boston, MA
| | - Imani E McElroy
- Division of Vascular and Endovascular Surgery Harvard Medical School, Massachusetts General Hospital Boston, MA
| | - Charles DeCarlo
- Division of Vascular and Endovascular Surgery Harvard Medical School, Massachusetts General Hospital Boston, MA
| | - Tiffany R Bellomo
- Division of Vascular and Endovascular Surgery Harvard Medical School, Massachusetts General Hospital Boston, MA
| | - Monica Majumdar
- Division of Vascular and Endovascular Surgery Harvard Medical School, Massachusetts General Hospital Boston, MA
| | - Srihari K Lella
- Division of Vascular and Endovascular Surgery Harvard Medical School, Massachusetts General Hospital Boston, MA
| | - Jahan Mohebali
- Division of Vascular and Endovascular Surgery Harvard Medical School, Massachusetts General Hospital Boston, MA
| | - Anahita Dua
- Division of Vascular and Endovascular Surgery Harvard Medical School, Massachusetts General Hospital Boston, MA.
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He Q, Zhou Y, Liu C, Chen Z, Wen R, Wu Y, Xie Z, Cheng Y, Cheng S. Prediction of Hematoma Expansion in Patients With Intracerebral Hemorrhage Using Thromboelastography With Platelet Mapping: A Prospective Observational Study. Front Neurol 2021; 12:746024. [PMID: 34721271 PMCID: PMC8553958 DOI: 10.3389/fneur.2021.746024] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2021] [Accepted: 09/15/2021] [Indexed: 01/02/2023] Open
Abstract
Background and Purpose: The purpose of the study was to evaluate the usefulness of thromboelastography with platelet mapping (TEG-PM) for predicting hematoma expansion (HE) and poor functional outcome in patients with intracerebral hemorrhage (ICH). Methods: Patients with primary ICH who underwent baseline computed tomography (CT) and TEG-PM within 6 h after symptom onset were enrolled in the observational cohort study. We performed univariate and multivariate logistic regression models to assess the association of admission platelet function with HE and functional outcome. In addition, a receiver operating characteristic (ROC) curve analysis investigated the accuracy of platelet function in predicting HE. A mediation analysis was undertaken to determine causal associations among platelet function, HE, and outcome. Results: Of 142 patients, 37 (26.1%) suffered HE. Multivariate logistic regression identified arachidonic acid (AA) and adenosine diphosphate (ADP) inhibition as significant independent predictors of HE. The area under the ROC curves was 0.727 for AA inhibition and 0.721 for ADP inhibition. Optimal threshold for AA inhibition was 41.75% (75.7% sensitivity; 67.6% specificity) and ADP inhibition was 65.8% (73.0% sensitivity; 66.7% specificity). AA and ADP inhibition were also associated with worse 3-month outcomes after adjusting for age, admission Glasgow Coma Scale score, intraventricular hemorrhage, baseline hematoma volume, and hemoglobin. The mediation analysis showed that the effect of higher platelet inhibition with poor outcomes was mediated through HE. Conclusions: These findings suggest that the reduced platelet response to ADP and AA independently predict HE and poor outcome in patients with ICH. Platelet function may represent a modifiable target of ICH treatment.
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Affiliation(s)
- Qiuguang He
- Department of Neurosurgery, The Second Affiliated Hospital of Chongqing Medical University, Chongqing, China
| | - You Zhou
- Department of Critical Care Medicine, The Second Affiliated Hospital of Chongqing Medical University, Chongqing, China
| | - Chang Liu
- Department of Neurology, The Second Affiliated Hospital of Chongqing Medical University, Chongqing, China
| | - Zhongqiu Chen
- Department of Information Center, The Second Affiliated Hospital of Chongqing Medical University, Chongqing, China
| | - Rong Wen
- Department of Neurosurgery, The Second Affiliated Hospital of Chongqing Medical University, Chongqing, China
| | - Yue Wu
- Department of Neurosurgery, The First Affiliated Hospital of Chongqing Medical University, Chongqing, China
| | - Zongyi Xie
- Department of Neurosurgery, The Second Affiliated Hospital of Chongqing Medical University, Chongqing, China
| | - Yuan Cheng
- Department of Neurosurgery, The Second Affiliated Hospital of Chongqing Medical University, Chongqing, China
| | - Si Cheng
- Department of Orthopedics, The Second Affiliated Hospital of Chongqing Medical University, Chongqing, China
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Tantry US, Hartmann J, Neal MD, Schöechl H, Bliden KP, Agarwal S, Mason D, Dias JD, Mahla E, Gurbel PA. The role of viscoelastic testing in assessing peri-interventional platelet function and coagulation. Platelets 2021; 33:520-530. [PMID: 34369848 DOI: 10.1080/09537104.2021.1961709] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
We carried out a literature search in MEDLINE (PubMed) and EMBASE literature databases to provide a concise review of the role of viscoelastic testing in assessing peri-interventional platelet function and coagulation. The search identified 130 articles that were relevant for the review, covering the basic science of VHA and VHA in clinical settings including cardiac surgery, cardiology, neurology, trauma, non-cardiac surgery, obstetrics, liver disease, and COVID-19. Evidence from these articles is used to describe the important role of VHAs and platelet function testing in various peri-interventional setups. VHAs can help us to comprehensively assess the contribution of platelets and coagulation dynamics to clotting at the site-of-care much faster than standard laboratory measures. In addition to standard coagulation tests, VHAs are beneficial in reducing allogeneic transfusion requirements and bleeding, in predicting ischemic events, and improving outcomes in several peri-interventional care settings. Further focused studies are needed to confirm their utility in the peri-interventional case.
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Affiliation(s)
- Udaya S Tantry
- Sinai Center for Thrombosis Research and Drug Development, Sinai Hospital of Baltimore, Baltimore, MD, USA
| | - Jan Hartmann
- Medical Affairs and Clinical Development, Haemonetics Corporation, Boston, MA, USA
| | - Matthew D Neal
- Department of General Surgery, The University of Pittsburgh Medical Center, Pittsburgh, PA, USA
| | - Herbert Schöechl
- Department of Anesthesiology and Intensive Care Medicine, AUVA Trauma Centre Salzburg, Academic Teaching Hospital of the Paracelsus Medical University, Salzburg, Austria.,AUVA Trauma Research Centre, Ludwig Boltzmann Institute for Experimental and Clinical Traumatology, Vienna, Austria
| | - Kevin P Bliden
- Sinai Center for Thrombosis Research and Drug Development, Sinai Hospital of Baltimore, Baltimore, MD, USA
| | - Seema Agarwal
- Department of Anaesthesia, Manchester University Foundation Trust, Manchester, UK
| | - Dan Mason
- Medical Affairs and Clinical Development, Haemonetics Corporation, Boston, MA, USA
| | - Joao D Dias
- Medical Affairs and Clinical Development, Haemonetics Corporation, Boston, MA, USA
| | - Elisabeth Mahla
- Department of Anaesthesiology and Intensive Care Medicine, Medical University of Graz, Graz, Austria
| | - Paul A Gurbel
- Sinai Center for Thrombosis Research and Drug Development, Sinai Hospital of Baltimore, Baltimore, MD, USA
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Dias JD, Pottgiesser T, Hartmann J, Duerschmied D, Bode C, Achneck HE. Comparison of three common whole blood platelet function tests for in vitro P2Y12 induced platelet inhibition. J Thromb Thrombolysis 2021; 50:135-143. [PMID: 31620937 PMCID: PMC7293977 DOI: 10.1007/s11239-019-01971-1] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
In the context of interventional cardiology, platelet function testing may identify patients treated with P2Y12-inhibitors at an increased risk of mortality, thrombosis and bleeding. Several whole blood point-of-care platelet function analyzers are available; however, inter-device differences have not been examined systematically. To compare three platelet function tests under standardized in vitro conditions. Healthy volunteer (n = 10) blood samples were spiked with increasing concentrations of ticagrelor (0–7500 ng/mL) and/or ASA (0–3280 ng/mL), measured on three platelet function analyzers (TEG®6s, Multiplate®, and VerifyNow®) and respective Effective Concentration (EC) levels EC10, EC50 and EC90 were calculated. Repeatability was assessed in a separate group of pooled blood samples (n = 10) spiked with ticagrelor at EC10, EC50 and EC90. ASA had no impact on ADP-activated channels for all three devices. TEG®6s was able to distinguish (p ≤ 0.05) between all ticagrelor EC zones; VerifyNow® and Multiplate® were able to distinguish between three and two zones, respectively. Multiplate® showed the largest window between EC10 and EC90 (19–9153 ng/mL), followed by TEG®6s (144–2589 ng/mL), and VerifyNow® (191–1100 ng/mL). Drug effect models distribution of disagreements were identified for TEG®6s (5.0%), VerifyNow® (8.3%), and Multiplate® (13.3%). TEG®6s showed the smallest average coefficient of variation between EC conditions (5.1%), followed by Multiplate® (14.1%), and VerifyNow® (17.7%). Linear models could be generated between TEG®6s and Multiplate®, but not VerifyNow®. Significant differences were found between whole blood point-of-care platelet function analyzers and the clinical impact of these differences needs to be further investigated.
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Affiliation(s)
| | - Torben Pottgiesser
- Department of Cardiology and Angiology I, Faculty of Medicine, Heart Center Freiburg University, University of Freiburg, Freiburg, Germany
| | | | - Daniel Duerschmied
- Department of Cardiology and Angiology I, Faculty of Medicine, Heart Center Freiburg University, University of Freiburg, Freiburg, Germany
| | - Christoph Bode
- Department of Cardiology and Angiology I, Faculty of Medicine, Heart Center Freiburg University, University of Freiburg, Freiburg, Germany
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Viscoelastic Hemostatic Assays and Platelet Function Testing in Patients with Atherosclerotic Vascular Diseases. Diagnostics (Basel) 2021; 11:diagnostics11010143. [PMID: 33478051 PMCID: PMC7835760 DOI: 10.3390/diagnostics11010143] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2020] [Revised: 01/14/2021] [Accepted: 01/18/2021] [Indexed: 11/16/2022] Open
Abstract
Platelets play crucial role in acute vascular atherosclerotic diseases, including myocardial infarction and stroke. Additionally, platelet aggregation is a key target of antiplatelet agents, forming the keystone of pharmacotherapy of various atherosclerotic cardiovascular diseases. Thromboelastography and thromboelastometry, representing currently available viscoelastic hemostatic assays (VHA), are designed as whole blood, real-time analyzers of clot formation and clot resolution. These assays could, in theory, overcome some limitations of currently available platelet function testing assays. This article reviews the current experience with the use of VHA for platelet function testing and for monitoring of the response to antiplatelet therapy.
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Agarwal S, Abdelmotieleb M. Viscoelastic testing in cardiac surgery. Transfusion 2020; 60 Suppl 6:S52-S60. [PMID: 32955756 DOI: 10.1111/trf.16075] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2020] [Revised: 06/30/2020] [Accepted: 06/30/2020] [Indexed: 11/30/2022]
Abstract
Bleeding complications are common in cardiac surgery and lead to an increase in morbidity and mortality. This is multifactorial in aetiology including the effects of cardiopulmonary bypass, the drugs given to manipulate the coagulation system and the vascular nature of the surgery itself. Viscoelastic tests provide a point of care, rapid assessment of coagulation which offer the advantage of faster turnaround times and a nuanced view of the elements of the coagulation system allowing targeted therapy to be delivered quickly. Both thomboelastography (TEG)and thromboelastometry (ROTEM) have been recommended for use in cardiac surgery, both have shown a reduction in transfusion and bleeding when used as part of a testing algorithm. They are particularly useful in assessing residual heparinisation and fibrinogen levels. Additionally, TEG allows the evaluation of the effects of anti-platelet agents on platelet function. This review discusses the mechanisms by which bleeding occurs in cardiac surgery and explores three uses of viscoelastic testing in cardiac surgery: to predict bleeding, to assess platelet function and peri-operative testing to reduce transfusion.
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Affiliation(s)
- Seema Agarwal
- Department of Cardiothoracic Anaesthesia and ICM, Manchester University Foundation Trust, Manchester, UK
| | - Mohamed Abdelmotieleb
- Department of Cardiothoracic Anaesthesia and ICM, Manchester University Foundation Trust, Manchester, UK
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Corliss BM, Freedman R, Brennan MM, Smith J, Nerva JD, Harris NS, Polifka AJ, Hoh BL, Fox WC. Laboratory assessments of therapeutic platelet inhibition in endovascular neurosurgery: complication prediction using the VerifyNow P2Y12 assay and thromboelastography with platelet mapping. J Neurosurg 2020; 134:884-892. [PMID: 32084635 DOI: 10.3171/2019.12.jns192396] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2019] [Accepted: 12/02/2019] [Indexed: 11/06/2022]
Abstract
OBJECTIVE Inhibition of platelet aggregation is universally used to prevent thromboembolic complications related to stent placement in endovascular neurosurgery, but excessive inhibition potentiates hemorrhagic complications. Previously, the authors demonstrated that two different commercially available measures of adenosine diphosphate (ADP)-dependent platelet inhibition-the VerifyNow P2Y12 clopidogrel assay (measured in platelet reactivity units [PRU]) and maximal amplitude (MA) attributable to ADP activity (MA-ADP) derived from thromboelastography (TEG) with platelet mapping (PM)-yielded wildly different results. This study sought to analyze observed complications to quantify the ideal therapeutic windows for both tests. METHODS Ninety-one patients with simultaneous or near-simultaneous PRU and TEG-PM results who underwent craniocervical endovascular stenting at the authors' institution between September 2015 and November 2017 were identified and retrospectively enrolled. From November 2017 until June 2019, 109 additional patients were prospectively enrolled. For this study, in-hospital thrombotic and hemorrhagic complications (both CNS and non-CNS) were tabulated, and receiver operating characteristic (ROC) curve analysis was used to identify threshold values of the PRU and MA-ADP for predicting each type of complication. RESULTS Of the 200 patients enrolled, 7 were excluded because of anemia or thrombocytopenia outside of the test manufacturer's specified ranges and 1 was excluded because they did not have a TEG-PM result. Including complications of all severities, there were a total of 15 CNS thrombotic complications, 1 access-site thrombotic complication, 3 CNS hemorrhages, 8 access-site hemorrhagic complications, and 3 hemorrhagic complications not affecting either the CNS or the access site. ROC curve analysis yielded therapeutic threshold values of 118-144 PRU. The results demonstrated PRU has a significant dose-dependent effect on the rates of thrombosis and hemorrhage. Logistic regression models did not demonstrate statistically significant relationships between the MA-ADP and either thrombosis or hemorrhage. ROC analysis based on these models is of little value and did not identify significant threshold values for MA-ADP. CONCLUSIONS There continues to be poor correlation between the results of TEG-PM and PRU. PRU accurately predicted complications, with a relatively narrow ideal value range of 118-144. The MA-ADP alone does not appear able to accurately predict either hemorrhagic or thrombotic complications in this group.
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Affiliation(s)
| | - Rachel Freedman
- 2University of Florida College of Medicine, Gainesville, Florida; and
| | | | | | - John D Nerva
- 4Department of Neurological Surgery, Tulane University, Metairie, Louisiana
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Zhang L, Li X, Wang D, Lv H, Si X, Li X, Sun Y, Wang D, Chen K, Kang X, Lou X, Zhang G, Ma N. Risk Factors of Recurrent Ischemic Events after Acute Noncardiogenic Ischemic Stroke. Curr Pharm Des 2020; 25:4827-4834. [PMID: 31663472 DOI: 10.2174/1381612825666191029103756] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2019] [Accepted: 10/21/2019] [Indexed: 11/22/2022]
Abstract
Background:
A considerable proportion of acute noncardiogenic ischemic stroke patients continue to
experience recurrent ischemic events after standard therapy.
Aim:
We aimed to identify risk factors for recurrent ischemic event prediction at an early stage.
Methods :
286 non-cardioembolic ischemic stroke patients with the onset of symptoms within 24 hours were
enrolled. Vascular risk factors, routine laboratory data on admission, thromboelastography test seven days after
clopidogrel therapy and any recurrent events within one year were assessed. Patients were divided into case group
(patients with clinical adverse events, including ischemic stokes, transient ischemic attack, myocardial infarction
and vascular related mortality) and control group (events-free patients). The risk of the recurrent ischemic events
was determined by the receiver operating characteristic curve and multivariable logistic regression analysis.
Results:
Clinical adverse events were observed in 43 patients (case group). The mean levels of Mean Platelet
Volume (MPV), Platelet/Lymphocyte Ratio (PLR), Lymphocyte Count (LY) and Fibrinogen (Fib) on admission
were significantly higher in the case group as compared to the control group (P<0.001). Seven days after clopidogrel
therapy, the ADP-induced platelet inhibition rate (ADP%) level was lower in the case group, while the
Maximum Amplitude (MA) level was higher in the case group as compared to the control group (P<0.01). The
Area Under the Curve (AUC) of receiver operating characteristic(ROC) curve of LY, PLR, , Fib, MA, ADP% and
MPV were 0.602, 0.614, 0.629, 0.770, 0.800 and 0.808, respectively. The logistic regression analysis showed that
MPV, ADP% and MA were indeed predictive factors.
Conclusion:
MPV, ADP% and MA were risk factors of recurrent ischemic events after acute noncardiogenic
ischemic stroke. Urgent assessment and individual drug therapy should be offered to these patients as soon as
possible.
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Affiliation(s)
- Limin Zhang
- Laboratory Diagnosis Center, Beijing Tiantan Hospital, Capital Medical University, Beijing, 100070, China
| | - Xingang Li
- Department of Pharmacy, Beijing Friendship Hospital, Capital Medical University, Beijing, 100050, China
| | - Dongzhi Wang
- Laboratory Diagnosis Center, Beijing Tiantan Hospital, Capital Medical University, Beijing, 100070, China
| | - Hong Lv
- Laboratory Diagnosis Center, Beijing Tiantan Hospital, Capital Medical University, Beijing, 100070, China
| | - Xuezhong Si
- Laboratory Diagnosis Center, Beijing Tiantan Hospital, Capital Medical University, Beijing, 100070, China
| | - Xiao Li
- Laboratory Diagnosis Center, Beijing Tiantan Hospital, Capital Medical University, Beijing, 100070, China
| | - Yuehong Sun
- Laboratory Diagnosis Center, Beijing Tiantan Hospital, Capital Medical University, Beijing, 100070, China
| | - Dan Wang
- Laboratory Diagnosis Center, Beijing Tiantan Hospital, Capital Medical University, Beijing, 100070, China
| | - Kelin Chen
- Laboratory Diagnosis Center, Beijing Tiantan Hospital, Capital Medical University, Beijing, 100070, China
| | - Xixiong Kang
- Laboratory Diagnosis Center, Beijing Tiantan Hospital, Capital Medical University, Beijing, 100070, China
| | - Xin Lou
- Department of Radiology, Chinese PLA General Hospital, Beijing, 100853, China
| | - Guojun Zhang
- Laboratory Diagnosis Center, Beijing Tiantan Hospital, Capital Medical University, Beijing, 100070, China
| | - Ning Ma
- Department of Interventional Neuroradiology, Beijing Tiantan Hospital, Capital Medical University, China National Clinical Research Center for Neurological Diseases, Center of Stroke, Beijing Institute for Brain Disorders, Beijing, 100070, China
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Corliss BM, Polifka AJ, Harris NS, Hoh BL, Fox WC. Laboratory assessments of therapeutic platelet inhibition in endovascular neurosurgery: comparing results of the VerifyNow P2Y12 assay to thromboelastography with platelet mapping. J Neurosurg 2019; 129:1160-1165. [PMID: 29271717 DOI: 10.3171/2017.6.jns17535] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2017] [Accepted: 06/05/2017] [Indexed: 12/24/2022]
Abstract
OBJECTIVEInhibition of platelet aggregation is vital to preventing thromboembolic complications related to stent placement in endovascular neurosurgery, but excessive inhibition potentiates hemorrhagic complications. Recent evidence suggests an ideal inhibition range of 70-150 P2Y12 response units (PRU) as measured on the VerifyNow assay, which relies on photometric measurements of platelet aggregation. Thromboelastography (TEG) with platelet mapping (PM) is an alternative assay that directly measures clot formation and mechanical strength. This study compares the results of PRU to TEG-PM.METHODSPatients with simultaneous or near-simultaneous PRU and TEG-PM results who underwent cervical carotid artery stenting, intracranial stent-assisted aneurysm coiling, or flow diversion at the authors' institution between August 2015 and November 2016 were identified. PRU results were compared with the TEG maximal amplitude (MA) attributable to adenosine diphosphate (ADP) activity (MA-ADP) as measured by TEG-PM. Platelet inhibition was considered therapeutic for MA-ADP values < 50 mm or PRU < 194. The Pearson correlation coefficient was calculated, and the sensitivity and specificity of PRU were calculated assuming that the results of TEG-PM reflected the true degree of platelet inhibition.RESULTSTwenty-three patients were identified with a total of 37 matched sets of TEG-PM and PRU. Three of these pairs were excluded due to anemia outside of the PRU manufacturer's recommended range. The Pearson correlation coefficient for these values was 0.50 (p = 0.0026). The prevalence of clopidogrel nonresponders determined by TEG-PM (9%) matched reported rates (5%-12%); PRU demonstrated much higher prevalence (39%). For detecting a therapeutic level of platelet inhibition, PRU demonstrated a sensitivity of 0.59, specificity of 0.50, positive predictive value of 0.95, and negative predictive value of 0.07. Ideal inhibition was concordant in only 25% of observations in which at least one of the results was ideal.CONCLUSIONSAgreement between TEG-PM and PRU regarding the degree of platelet inhibition is poor. PRU likely overestimates clopidogrel resistance, as 93% of patients with PRU > 194 demonstrate a therapeutic level of platelet inhibition on TEG.
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Affiliation(s)
| | | | - Neil S Harris
- 2Pathology, University of Florida, Gainesville, Florida
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14
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Abstract
Agreement between estimated fibrinogen concentration via thromboelastography and traditional assays is not established in the parturient. We therefore recruited 56 parturients and performed Clauss and functional fibrinogen level (FLEV) tests. Mean difference of measurements was 36.8 mg/dL (95% CI, 21.8-51.9) with a standard deviation of 52.8 mg/dL. Calculated limits of agreement were 140.2 mg/dL (95% CI, 166.3-114.6) and -66.6 mg/dL (95% CI, -40.8 to -92.5), within the maximum allowable difference of 165 mg/dL. We therefore conclude that while most measurements fell within the limits of agreement, more work is needed to clearly define the role of this test in the obstetric population.
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Affiliation(s)
- Daniel Katz
- From the Department of Anesthesiology, Pain, and Perioperative Medicine, Icahn School of Medicine at Mount Sinai, New York, New York
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15
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Hartmann J. External Quality Assurance of Platelet Function Assays: Results of the College of American Pathologists Proficiency Testing Program. Arch Pathol Lab Med 2019; 143:914-916. [PMID: 31339756 DOI: 10.5858/arpa.2019-0115-le] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Affiliation(s)
- Jan Hartmann
- Medical Affairs, Haemonetics Corp, Braintree, Massachusetts
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16
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Azarfarin R, Noohi F, Kiavar M, Totonchi Z, Heidarpour A, Hendiani A, Koleini ZS, Rahimi S. Relationship between maximum clot firmness in ROTEM ® and postoperative bleeding after coronary artery bypass graft surgery in patients using clopidogrel. Ann Card Anaesth 2018; 21:175-180. [PMID: 29652280 PMCID: PMC5914219 DOI: 10.4103/aca.aca_139_17] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023] Open
Abstract
Background: The aim of the present study was to investigate the relationship between maximum clot firmness (MCF) in rotational thromboelastometry (ROTEM®) and postoperative bleeding in patients on clopidogrel after emergency coronary artery bypass graft surgery (CABG). Methods: This observational study recruited 60 patients posted for emergency CABG following unsuccessful primary percutaneous coronary intervention (PCI) while on 600 mg of clopidogrel. The study population was divided into 2 groups on the basis of their MCF in the extrinsically activated thromboelastometric (EXTEM) component of the (preoperative) ROTEM® test: patients with MCF <50 mm (n = 16) and those with MCF ≥50 mm (n = 44). Postoperative chest tube drainage amount, need for blood product transfusion, postoperative complications, and duration of mechanical ventilation after CABG were recorded. Results: No significant differences were observed between the two groups regarding duration of surgery, cardiopulmonary bypass, and aortic cross-clamp time. Chest tube drainage at 6, 12, and 24 h after Intensive Care Unit admission were significantly higher in the patients with MCF below 50 mm. The need for blood product transfusion was higher in the group with MCF <50 mm. In patients who experienced postoperative bleeding of 1000 mL or more, the ROTEM® parameters of INTEM (Intrinsically activated thromboelastomery) α and MCF, EXTEM α and MCF, and HEPTEM (INTEM assay performed in the presence of heparinase) MCF (but not FIBTEM (Thromboelastometric assay for the fibrin part of the clot) values) were significantly lower than those with postoperative bleeding <1000 mL (P ≤ 0.05). Conclusions: When platelet aggregometry is not available, the ROTEM® test could be useful for the prediction of increased risk bleeding after emergency CABG in patients who have received a loading dose of clopidogrel.
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Affiliation(s)
- Rasoul Azarfarin
- Echocardiography Research Center, Rajaie Cardiovascular Medical and Research Center, University of Medical Sciences, Tehran, Iran
| | - Fereidoon Noohi
- Cardiac Intervention Research Center, Rajaie Cardiovascular Medical And Research Center, University of Medical Sciences, Tehran, Iran
| | - Majid Kiavar
- Cardiac Intervention Research Center, Rajaie Cardiovascular Medical And Research Center, University of Medical Sciences, Tehran, Iran
| | - Ziae Totonchi
- Rajaie Cardiovascular Medical and Research Center, University of Medical Sciences, Tehran, Iran
| | - Avaz Heidarpour
- Rajaie Cardiovascular Medical and Research Center, University of Medical Sciences, Tehran, Iran
| | - Amir Hendiani
- Faculty of Medicine, University of Medical Sciences, Tehran, Iran
| | | | - Saeid Rahimi
- Faculty of Medicine, University of Medical Sciences, Tehran, Iran
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17
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Mahla E, Tantry US, Prüller F, Gurbel PA. Is There a Role for Preoperative Platelet Function Testing in Patients Undergoing Cardiac Surgery During Antiplatelet Therapy? Circulation 2018; 138:2145-2159. [DOI: 10.1161/circulationaha.118.035160] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Affiliation(s)
- Elisabeth Mahla
- Department of Anesthesiology and Intensive Care Medicine (E.M.), Medical University of Graz, Austria
| | - Udaya S. Tantry
- Inova Center for Thrombosis Research and Drug Development, Inova Heart and Vascular Institute, Falls Church, VA (U.S.T., P.A.G.)
| | - Florian Prüller
- Clinical Institute of Medical and Chemical Laboratory Diagnostics (F.P.), Medical University of Graz, Austria
| | - Paul A. Gurbel
- Inova Center for Thrombosis Research and Drug Development, Inova Heart and Vascular Institute, Falls Church, VA (U.S.T., P.A.G.)
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18
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Dalal A. Organ transplantation and drug eluting stents: Perioperative challenges. World J Transplant 2016; 6:620-631. [PMID: 28058211 PMCID: PMC5175219 DOI: 10.5500/wjt.v6.i4.620] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/16/2016] [Revised: 07/18/2016] [Accepted: 09/18/2016] [Indexed: 02/05/2023] Open
Abstract
Patients listed for organ transplant frequently have severe coronary artery disease (CAD), which may be treated with drug eluting stents (DES). Everolimus and zotarolimus eluting stents are commonly used. Newer generation biolimus and novolimus eluting biodegradable stents are becoming increasingly popular. Patients undergoing transplant surgery soon after the placement of DES are at increased risk of stent thrombosis (ST) in the perioperative period. Dual antiplatelet therapy (DAPT) with aspirin and a P2Y12 inhibitor such as clopidogrel, prasugrel and ticagrelor is instated post stenting to decrease the incident of ST. Cangrelor has recently been approved by Food and Drug Administration and can be used as a bridging antiplatelet drug. The risk of ischemia vs bleeding must be considered when discontinuing or continuing DAPT for surgery. Though living donor transplant surgery is an elective procedure and can be optimally timed, cadaveric organ availability is unpredictable, therefore, discontinuation of antiplatelet medication cannot be optimally timed. The type of stent and timing of transplant surgery can be of utmost importance. Many platelet function point of care tests such as Light Transmittance Aggregrometry, Thromboelastography Platelet Mapping, VerifyNow, Multiple Electrode Aggregrometry are used to assess bleeding risk and guide perioperative platelet transfusion. Response to allogenic platelet transfusion to control severe intraoperative bleeding may differ with the antiplatelet drug. In stent thrombosis is an emergency where management with either a drug eluting balloon or a DES has shown superior outcomes. Post-transplant complications often involved stenosis of an important vessel that may need revascularization. DES are now used for endovascular interventions for transplant orthotropic heart CAD, hepatic artery stenosis post liver transplantation, transplant renal artery stenosis following kidney transplantation, etc. Several antiproliferative drugs used in the DES are inhibitors of mammalian target of rapamycin. Thus they are used for post-transplant immunosuppression to prevent acute rejection in recipients with heart, liver, lung and kidney transplantation. This article describes in detail the various perioperative challenges encountered in organ transplantation surgery and patients with drug eluting stents.
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19
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Keeling D, Tait RC, Watson H. Peri-operative management of anticoagulation and antiplatelet therapy. Br J Haematol 2016; 175:602-613. [DOI: 10.1111/bjh.14344] [Citation(s) in RCA: 127] [Impact Index Per Article: 15.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2016] [Revised: 07/26/2016] [Accepted: 07/31/2016] [Indexed: 12/14/2022]
Affiliation(s)
- David Keeling
- Oxford University Hospitals NHS Foundation Trust; Oxford UK
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20
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Agarwal S. Platelet function testing in cardiac surgery. Transfus Med 2016; 26:319-329. [PMID: 27535575 DOI: 10.1111/tme.12335] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2016] [Revised: 07/12/2016] [Accepted: 07/24/2016] [Indexed: 12/17/2022]
Abstract
Bleeding in cardiac surgery is known to cause increased morbidity and mortality. The rise in the use of anti-platelet medication has led to an increase in the number of patients presenting for cardiac surgery with platelet dysfunction, who are at a heightened risk of bleeding. However, the extent of platelet inhibition is well known to differ among individuals. In the past few years, a number of point-of-care platelet function testing devices, which may be able to assess platelet reactivity, have entered the market. This review will examine the devices most commonly studied and the evidence surrounding their use in cardiac surgery and their effect on blood loss.
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Affiliation(s)
- S Agarwal
- Department of Anaesthesia and Critical Care, Liverpool Heart and Chest Hospital, Liverpool, UK.
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21
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Raman VV, Kasivisvanathan R, Madhivathanan PR. A clinician's guide to viscoelastic testing in the perioperative period. Br J Hosp Med (Lond) 2016; 76:690-5. [PMID: 26646330 DOI: 10.12968/hmed.2015.76.12.690] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
Viscoelastic tests provide a global and dynamic assessment of the coagulation system and thus are becoming increasingly relied upon in the perioperative period. Many clinicians are unfamiliar with viscoelastic testing, so this article provides an overview of their use and interpretation in the management of perioperative bleeding.
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Affiliation(s)
- Vishal Venkat Raman
- Core Trainee in the Department of Anaesthesia, The Whittington Hospital NHS Trust, London N19 5NF
| | | | - Pradeep R Madhivathanan
- Consultant in Cardiothoracic Anaesthesia and Critical Care in the Department of Anaesthesia and Critical Care, King's College Hospital NHS Foundation Trust, London
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22
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Hans GA, Besser MW. The place of viscoelastic testing in clinical practice. Br J Haematol 2016; 173:37-48. [DOI: 10.1111/bjh.13930] [Citation(s) in RCA: 72] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Affiliation(s)
- Gregory A. Hans
- Department of Anaesthesia and Intensive Care Medicine; CHU of Liege; Liege Belgium
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23
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Clevenger B, Mallett SV, Klein AA, Richards T. Patient blood management to reduce surgical risk. Br J Surg 2015; 102:1325-37; discussion 1324. [PMID: 26313653 DOI: 10.1002/bjs.9898] [Citation(s) in RCA: 83] [Impact Index Per Article: 9.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2014] [Revised: 06/08/2015] [Accepted: 06/11/2015] [Indexed: 12/16/2022]
Abstract
BACKGROUND Preoperative anaemia and perioperative blood transfusion are both identifiable and preventable surgical risks. Patient blood management is a multimodal approach to address this issue. It focuses on three pillars of care: the detection and treatment of preoperative anaemia; the reduction of perioperative blood loss; and harnessing and optimizing the patient-specific physiological reserve of anaemia, including restrictive haemoglobin transfusion triggers. This article reviews why patient blood management is needed and strategies for its incorporation into surgical pathways. METHODS Studies investigating the three pillars of patient blood management were identified using PubMed, focusing on recent evidence-based guidance for perioperative management. RESULTS Anaemia is common in surgical practice. Both anaemia and blood transfusion are independently associated with adverse outcomes. Functional iron deficiency (iron restriction due to increased levels of hepcidin) is the most common cause of preoperative anaemia, and should be treated with intravenous iron. Intraoperative blood loss can be reduced with antifibrinolytic drugs such as tranexamic acid, and cell salvage should be used. A restrictive transfusion practice should be the standard of care after surgery. CONCLUSION The significance of preoperative anaemia appears underappreciated, and its detection should lead to routine investigation and treatment before elective surgery. The risks of unnecessary blood transfusion are increasingly being recognized. Strategic adoption of patient blood management in surgical practice is recommended, and will reduce costs and improve outcomes in surgery.
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Affiliation(s)
- B Clevenger
- Division of Surgery and Interventional Science, University College London, London, UK.,Royal Free Perioperative Research Group, Department of Anaesthesia, Royal Free Hospital, London, UK
| | - S V Mallett
- Division of Surgery and Interventional Science, University College London, London, UK.,Royal Free Perioperative Research Group, Department of Anaesthesia, Royal Free Hospital, London, UK
| | - A A Klein
- Department of Anaesthesia and Intensive Care, Papworth Hospital, Cambridge, UK
| | - T Richards
- Division of Surgery and Interventional Science, University College London, London, UK
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24
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Mallett SV, Armstrong M. Point-of-care monitoring of haemostasis. Anaesthesia 2014; 70 Suppl 1:73-7, e25-6. [DOI: 10.1111/anae.12909] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 08/01/2014] [Indexed: 12/18/2022]
Affiliation(s)
- S. V. Mallett
- Department of Anaesthesia; Royal Free London NHS Trust; London UK
| | - M. Armstrong
- Department of Anaesthesia; Royal Free London NHS Trust; London UK
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