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Shadlyn T, Bauman M, Tandon P, Yap J, Kawada P. Accuracy and Precision of Point-of-Care International Normalized Ratio in Patients With Liver Disease. J Pediatr Gastroenterol Nutr 2023; 76:704-709. [PMID: 36800295 DOI: 10.1097/mpg.0000000000003744] [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] [Indexed: 02/18/2023]
Abstract
OBJECTIVE To determine if the CoaguChek XS Pro Point-of-Care (POC) device can accurately and precisely measure the international normalized ratio (INR) compared with the gold standard laboratory INR in pediatric and adult patients with liver disease. METHODS This prospective cohort study included 15 pediatric patients without liver disease, 13 pediatric patients with liver disease, and 17 adult patients with liver disease. The accuracy of the POC INR values was determined using the correlation and Bland-Altman limits of agreement. The accuracy of the coagulometer INR was assessed by calculating the proportion of POC INR measurements that were ≤15% of their corresponding laboratory INR. RESULTS A comparison of INR measurements showed an excellent correlation in pediatric patients without liver disease ( r = 0.82), pediatric patients with liver disease ( r = 0.89), and adult patients with liver disease ( r = 0.96). Fourteen (93%) POC INR values were ≤15% in pediatric patients without liver disease from its paired laboratory INR. All 13 paired measurements were ≤15% in pediatric patients with liver disease. In adult patients with liver disease, 12 (71%) POC INR values were ≤15% of their paired laboratory INR. CONCLUSIONS In patients with liver disease, the CoaguChek XS Pro provides an accurate measure of the INR compared to laboratory INR measurements.
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Affiliation(s)
- Tevyn Shadlyn
- From the Sackler Faculty of Medicine, Tel Aviv University, Tel Aviv, Israel
| | - Mary Bauman
- the Department of Pediatrics, University of Alberta, Edmonton, Alberta, Canada
| | - Puneeta Tandon
- the Division of Gastroenterology (Liver Unit), University of Alberta, Edmonton, Alberta, Canada
| | - Jason Yap
- the Department of Gastroenterology, Royal Children's Hospital, Melbourne, Victoria, Australia
| | - Patricia Kawada
- the Division of Pediatric Gastroenterology and Nutrition, Department of Pediatrics, Edmonton Clinic Health Academy (ECHA), Edmonton, Alberta, Canada
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Cortina-de-la-Rosa E, Izaguirre-Ávila R, Ramírez-Hernández A, Romero-Arroyo MO, Cortés-Cortés K. Reliability of International Normalized Ratio Results in the CoaguChek Pro II System in a Clinical Setting. Clin Appl Thromb Hemost 2023; 29:10760296231216451. [PMID: 38018118 PMCID: PMC10686019 DOI: 10.1177/10760296231216451] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/2023] [Revised: 10/27/2023] [Accepted: 11/07/2023] [Indexed: 11/30/2023] Open
Abstract
The National Institute of Cardiology has previously used the CoaguChek® XS Plus system (Roche Diagnostics International Ltd), comparing capillary blood prothrombin time/international normalized ratio (PT/INR) results with those obtained using BCS-XP/Thromborel (Siemens). We assessed the reliability of PT/INR results using the third-generation CoaguChek Pro II system, the CoaguChek XS Plus system, and cobas® t 411 for citrated plasma analysis. Venous and capillary PT/INR were measured (N = 204). Spearman's correlation, Bland-Altman, and concordance analysis between methods were conducted. Spearman's correlation coefficients between venous/capillary INR were high for CoaguChek Pro II versus CoaguChek XS Plus (r = 0.994), CoaguChek Pro II versus cobas t 411 (r = 0.967), and CoaguChek XS Plus versus cobas t 411 (r = 0.968). Good concordance was observed among capillary methods (concordance coefficient [κ] = 0.888) and remaining relationships (P < .001 for all): cobas t 411 versus CoaguChek XS Plus (κ = 0.696) and cobas t 411 versus CoaguChek Pro II (κ = 0.684). In conclusion, good agreement was observed between CoaguChek Pro II, CoaguChek XS Plus, and cobas t 411.
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Affiliation(s)
| | - Raúl Izaguirre-Ávila
- Department of Hematology, National Institute of Cardiology Ignacio Chávez, México City, México
| | | | | | - Karen Cortés-Cortés
- Department of Hematology, National Institute of Cardiology Ignacio Chávez, México City, México
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van den Heuvel J, Kena N, van Hattum T, van Dolder D, van Wijnen M. Evaluation of the analytical and clinical performance of the Micropoint qLabs INR point-of-care system. Thromb Res 2019; 176:104-107. [DOI: 10.1016/j.thromres.2019.02.012] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2018] [Revised: 11/13/2018] [Accepted: 02/11/2019] [Indexed: 10/27/2022]
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Mbokota N, Schapkaitz E, Louw S. Verification of the qLabs international normalized ratio point-of-care device for monitoring of patients attending an anticoagulation clinic. Int J Lab Hematol 2018; 40:508-514. [PMID: 29761633 DOI: 10.1111/ijlh.12849] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2018] [Accepted: 03/29/2018] [Indexed: 01/09/2023]
Abstract
INTRODUCTION In the developing world, point-of-care (POC) testing for international normalized ratio (INR) plays an important role in the monitoring of patients on long-term warfarin therapy with limited access to healthcare ensuring safe and effective anticoagulation. A newly developed POC device for INR measurement by healthcare workers is the handheld qLabs POC device® (Micropoint Biotechnologies Incorporated, Guangdong, China). METHODS The qLabs POC device® was evaluated in 262 patients attending an anticoagulation clinic with regards to accuracy and precision of the INR results. The results were compared to the results obtained on the Stago STA R Max® coagulation analyzer (Stago Diagnostica, Paris, France) on a wide range of normal and abnormal results of clinical relevance. RESULTS The mean laboratory INR (2.50 ± 1.08) was significantly higher than the qLabs POC device® INR (2.38 ± 1.07) (P < .0001). The correlation coefficient (r) was .88, the slope coefficient was 1.0 (CI, 0.8-1.2), and the intercept was -0.10 (CI, -0.50 to 0.30). The mean of the differences was -0.13% (CI, -0.19 to -0.06). Dosage concordance was 85.46% and clinical agreement was 92.37%. However, clinical agreement was 42.42% in the subgroup above the target range (>3.5). The imprecision was within acceptable limits (<5%) and the error message rate was 4.38%. CONCLUSION In conclusion, the qLabs POC device® is accurate and precise with high levels of dosage concordance and clinical agreement for INR values within and below the target range.
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Affiliation(s)
- N Mbokota
- Department of Molecular Medicine and Haematology, University of Witwatersrand Medical School, Johannesburg, South Africa
| | - E Schapkaitz
- Department of Molecular Medicine and Haematology, University of Witwatersrand Medical School, Johannesburg, South Africa
| | - S Louw
- Department of Molecular Medicine and Haematology, University of Witwatersrand Medical School, Johannesburg, South Africa
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Louw S, Mayne ES, Wan YO. Validation of the Mission® PTCoagulation Monitoring point-of-care device for the outpatient management of patients on long-term warfarin therapy. Int J Lab Hematol 2018; 40:e71-e73. [DOI: 10.1111/ijlh.12839] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2018] [Accepted: 03/27/2018] [Indexed: 11/30/2022]
Affiliation(s)
- S. Louw
- Department of Molecular Medicine and Haematology; National Health Laboratory Service (NHLS); Johannesburg South Africa
| | - E. S. Mayne
- Department of Molecular Medicine and Haematology; University of the Witwatersrand; Johannesburg South Africa
| | - Y. O. Wan
- Department of Molecular Medicine and Haematology; National Health Laboratory Service (NHLS); Johannesburg South Africa
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Shermock KM, Connor JT, Smith NT, Fink JM, Bragg L. Validity of Criteria Used to Evaluate Fingerstick Devices That Assess International Normalized Ratio. Med Decis Making 2016; 26:239-46. [PMID: 16751322 DOI: 10.1177/0272989x06288681] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Background . Investigators commonly rely on unvalidated, mainly arithmetic criteria to predict if point-of-care fingerstick devices that assess International Normalized Ratio (INR) lead to the same warfarin dosing decisions as a standard measure. Methods . Criteria that predict warfarin dosing agreement between 2 INR measurements were evaluated using clinicians’ actual dosing decisions as the standard. Bayesian hierarchical modeling was used to rank the criteria by the proportion of correct dosing predictions and the magnitude of difference between actual and predicted dosing agreement. Results . The prediction criteria misclassified dosing agreement for between 19% and 38% of paired INR values (x̄x: 27%). The magnitude of misclassification varied inconsistently throughout the INR scale. Conclusion . The unvalidated criteria used to predict warfarin dosing agreement between 2 INR measurements are associated with large error. Warfarin dosing decisions should be measured directly in such assessments.
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Affiliation(s)
- Kenneth M Shermock
- Center for Pharmaceutical Outcomes and Policy, The Johns Hopkins Hospital, Baltimore, MD 21287-6180, and Department of Statistics, H. John Heinz III School of Public Policy and Management, Carnegie Mellon University, Pittsburgh, PA, USA.
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Dillinger JG, Si Moussi T, Berge N, Bal Dit Sollier C, Henry P, Drouet L. Accuracy of point of care coagulometers compared to reference laboratory measurements in patients on oral anticoagulation therapy. Thromb Res 2016; 140:66-72. [DOI: 10.1016/j.thromres.2016.02.006] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2015] [Revised: 02/03/2016] [Accepted: 02/04/2016] [Indexed: 10/22/2022]
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Bruch TP, Mendes DC, Pedrozo JC, Figueiredo L, Nóvak EM, Zétola VF, Lange MC. Is point-of-care accurate for indicating thrombolysis in anticoagulated patients on oral anticoagulation treatments? ARQUIVOS DE NEURO-PSIQUIATRIA 2014; 72:487-9. [PMID: 25054978 DOI: 10.1590/0004-282x20140075] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/11/2013] [Accepted: 05/06/2014] [Indexed: 11/22/2022]
Abstract
UNLABELLED The use of oral anticoagulation treatment (OAT) in patients with an international normalized ratio (INR) higher than 1.7 is a contraindication to thrombolysis in acute ischemic stroke. The aim of the present study is to compare the use of point-of-care (POC) coagulometers to the standard coagulation analysis (SCA) procedure of the INR as a decision-making test for use with patients taking OAT. METHOD Eighty patients on chronic OAT underwent a POC and an SCA during a regular outpatient evaluation. RESULTS When comparing the abilities of the POC test and the SCA test to identify adequate levels for thrombolysis (≤1.7), the POC had a sensitivity of 96.6% (95%CI 88.4-99.1) and a specificity of 60.0% (95%CI 38.6-78). POC overestimated INR levels by 0.51 points compared to the SCA test. CONCLUSION POC has a high sensitivity compared to the SCA test for the identification of patients within the cut-off point for thrombolysis.
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Affiliation(s)
- Tatiana P Bruch
- Divisão de Neurologia, Hospital de Clínicas, Universidade Federal do Paraná, Curitiba, PR, Brazil
| | - Danielle C Mendes
- Divisão de Neurologia, Hospital de Clínicas, Universidade Federal do Paraná, Curitiba, PR, Brazil
| | - Jeff C Pedrozo
- Divisão de Neurologia, Hospital de Clínicas, Universidade Federal do Paraná, Curitiba, PR, Brazil
| | - Lívia Figueiredo
- Divisão de Neurologia, Hospital de Clínicas, Universidade Federal do Paraná, Curitiba, PR, Brazil
| | - Edison M Nóvak
- Divisão de Neurologia, Hospital de Clínicas, Universidade Federal do Paraná, Curitiba, PR, Brazil
| | - Viviane F Zétola
- Divisão de Neurologia, Hospital de Clínicas, Universidade Federal do Paraná, Curitiba, PR, Brazil
| | - Marcos C Lange
- Divisão de Neurologia, Hospital de Clínicas, Universidade Federal do Paraná, Curitiba, PR, Brazil
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Abstract
Background:In the emergency department, portable point-of-care testing (POCT) coagulation devices may facilitate stroke patient care by providing rapid International Normalized Ratio (INR) measurement. The objective of this study was to evaluate the reliability, validity, and impact on clinical decision-making of a POCT device for INR testing in the setting of acute ischemic stroke (AIS).Methods:A total of 150 patients (50 healthy volunteers, 51 anticoagulated patients, 49 AIS patients) were assessed in a tertiary care facility. The INR’s were measured using the Roche Coaguchek S and the standard laboratory technique.Results:The interclass correlation coefficient and 95% confidence interval between overall POCT device and standard laboratory value INRs was high (0.932 (0.69 - 0.78). In the AIS group alone, the correlation coefficient and 95% CI was also high 0.937 (0.59 - 0.74) and diagnostic accuracy of the POCT device was 94%.Conclusions:When used by a trained health professional in the emergency department to assess INR in acute ischemic stroke patients, the CoaguChek S is reliable and provides rapid results. However, as concordance with laboratory INR values decreases with higher INR values, it is recommended that with CoaguChek S INRs in the > 1.5 range, a standard laboratory measurement be used to confirm the results.
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Nagler M, Raddatz-Müller P, Schmid P, Bachmann LM, Wuillemin WA. Accuracy of the point-of-care coagulometer CoaguChek XS in the hands of patients. J Thromb Haemost 2013; 11:197-9. [PMID: 23121888 DOI: 10.1111/jth.12050] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- M Nagler
- Division of Hematology and Central Hematology Laboratory, Luzerner Kantonsspital, Lucerne, Switzerland
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11
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Diagnostic et prise en charge de la coagulopathie post-traumatique. Transfus Clin Biol 2012; 19:165-73. [DOI: 10.1016/j.tracli.2012.07.004] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2012] [Accepted: 07/21/2012] [Indexed: 11/21/2022]
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Utility of a point-of-care device for rapid determination of prothrombin time in trauma patients: a preliminary study. J Trauma Acute Care Surg 2012; 72:703-7. [PMID: 22491557 DOI: 10.1097/ta.0b013e31822c884d] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
BACKGROUND Rapid and accurate determination of prothrombin time in trauma patients may help to faster control of bleeding induced coagulopathy. The goal of this prospective observational study was to investigate the accuracy of bedside measurements of prothrombin time by the mean of a point-of-care device (INRatio) in trauma patients. METHODS Fifty blood samples were drawn at admission and during the acute care phase for standard coagulation assays (prothrombin time, International Normalized Ratio [INR], and fibrinogen) and INRatio testing (INR(A)) from 48 trauma patients. RESULTS Standard coagulation assays were available after a mean of 66 minutes. Median Injury Severity Score was 18, and 16 patients (33%) had a coagulopathy. Significant correlation was found between INR and INR(A) (r: 0.93, 95% confidence interval: 0.87-0.96). The mean difference (bias) for INR was 0.00, and standard deviation (precision) of the difference was 0.78. However, in cases where there was decreased hemoglobin (<10 gr · L(-1)) and fibrinogen (<1.5 gr · L(-1)), bias and precision were increased. To predict the need for fresh frozen plasma transfusion (INR > 1.5), INR(A) cutoff value of 1.3 resulted in a sensitivity of 92% and a specificity of 79%. The area under the receiver operating characteristic curve was 0.946 (95% confidence interval: 0,845-0,982). CONCLUSION INRatio may be a useful device in the management of trauma patients with ongoing or suspected coagulopathy that may help to save at least 60 minutes in the process of obtaining a prothrombin time result. It may allow earlier detection of coagulopathy and, together with vital sign and hemoglobin, may help to guide fresh frozen plasma transfusion.
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Christensen TD, Larsen TB. Precision and accuracy of point-of-care testing coagulometers used for self-testing and self-management of oral anticoagulation therapy. J Thromb Haemost 2012; 10:251-60. [PMID: 22118602 DOI: 10.1111/j.1538-7836.2011.04568.x] [Citation(s) in RCA: 71] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 08/31/2023]
Abstract
BACKGROUND Oral anticoagulation therapy is monitored by the use of the International Normalized Ratio (INR). Patients who perform self-testing or self-management use a point-of-care testing (POCT) coagulometer (INR monitor) to estimate their INRs. A precondition for a correct dosage of coumarins is a correct INR estimation, and the method and apparatus used for providing the INR measurements are crucial in this context. Several studies have been published regarding the precision and accuracy of these POCT coagulometers, and have led to diverse conclusions. It is difficult and challenging to perform an overview of the literature, owing to the vast amount of papers, with differences in design, statistical analysis, etc. OBJECTIVES The aim of this systematic review was to analyze the current literature, especially regarding the precision and accuracy of the POCT coagulometers, to provide recommendations for clinical use and quality control, and to point out areas for future research. METHODS We included a total of 22 studies, of which four were characterized as high-quality studies. RESULTS The precision of the POCT coagulometers was generally adequate for clinical use. Their performance in terms of accuracy has to be viewed in the context of the inherent inaccuracies of INR measurements. CONCLUSIONS The accuracy of POCT coagulometers seems, in this respect, to be generally acceptable, and they can be used in a clinical setting.
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Affiliation(s)
- T D Christensen
- Department of Cardiothoracic and Vascular Surgery & Institute of Clinical Medicine, Aarhus University Hospital, Aarhus N., Denmark.
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Ageno W, Gallus AS, Wittkowsky A, Crowther M, Hylek EM, Palareti G. Oral anticoagulant therapy: Antithrombotic Therapy and Prevention of Thrombosis, 9th ed: American College of Chest Physicians Evidence-Based Clinical Practice Guidelines. Chest 2012; 141:e44S-e88S. [PMID: 22315269 PMCID: PMC3278051 DOI: 10.1378/chest.11-2292] [Citation(s) in RCA: 1042] [Impact Index Per Article: 86.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 08/31/2011] [Indexed: 12/11/2022] Open
Abstract
BACKGROUND The objective of this article is to summarize the published literature concerning the pharmacokinetics and pharmacodynamics of oral anticoagulant drugs that are currently available for clinical use and other aspects related to their management. METHODS We carried out a standard review of published articles focusing on the laboratory and clinical characteristics of the vitamin K antagonists; the direct thrombin inhibitor, dabigatran etexilate; and the direct factor Xa inhibitor, rivaroxaban RESULTS The antithrombotic effect of each oral anticoagulant drug, the interactions, and the monitoring of anticoagulation intensity are described in detail and discussed without providing specific recommendations. Moreover, we describe and discuss the clinical applications and optimal dosages of oral anticoagulant therapies, practical issues related to their initiation and monitoring, adverse events such as bleeding and other potential side effects, and available strategies for reversal. CONCLUSIONS There is a large amount of evidence on laboratory and clinical characteristics of vitamin K antagonists. A growing body of evidence is becoming available on the first new oral anticoagulant drugs available for clinical use, dabigatran and rivaroxaban.
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Affiliation(s)
| | | | | | - Mark Crowther
- McMaster University, St. Joseph's Hospital, Hamilton, ON, Canada
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Kanagasabapathy P, Chowdary P, Gatt A. Alternatives to warfarin--the next generation of anticoagulants. Cardiovasc Ther 2010; 29:e80-8. [PMID: 20626755 DOI: 10.1111/j.1755-5922.2010.00197.x] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/21/2023] Open
Abstract
Anticoagulation therapy plays an important role in the management of cardiovascular disease. Currently, oral anticoagulation therapy is reliant on vitamin K antagonists (VKA). In clinical practice, VKA present several limitations including a narrow therapeutic window and frequent drug and food interactions. Despite the clear clinical need for alternative anticoagulants it is only within the last decade that significant progress has been made. These new anticoagulants target specific factors in the hemostatic network and appear to overcome some of the difficulties seen with VKA. Many have now progressed to phase III clinical trials including patients with cardiovascular disease. This review aims to highlight the exciting progress that has been made in the development of these new anticoagulants. It will focus on the key agents that have demonstrated the most promise in clinical trials to date. This will include data on cardiovascular indications for anticoagulant therapy. Finally, the review aims to analyze the future prospects for these new agents. Several issues remain to be addressed for these agents to finally replace vitamin K antagonists as the mainstay of anticoagulant therapy.
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Yelland LN, Gialamas A, Laurence CO, Willson KJ, Ryan P, Beilby JJ. Assessing agreement between point of care and pathology laboratory results for INR: experiences from the Point of Care Testing in General Practice Trial. Pathology 2010; 42:155-9. [PMID: 20085517 DOI: 10.3109/00313020903494045] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
AIMS To assess the level of agreement between international normalised ratio (INR) results obtained from pathology laboratories and point of care testing (PoCT) devices used in a general practice setting. METHODS INR pathology results were collected from multiple pathology laboratories and CoaguChek S PoCT devices over a 6 month period. Agreement was assessed using both clinically relevant agreement and the Bland Altman method. RESULTS Analysis was based on 1664 dual measurements collected on 417 patients from 26 general practices across Australia. The percentage of dual measurements satisfying the expanded and narrow agreement criteria were 91% and 89%, respectively. The mean difference in results and the 95% limits of agreement depended on the average INR result: mean difference = -0.30 + 0.08 x average; 95% limits of agreement = -0.30 + 0.08 x average +/- 0.77. CONCLUSIONS The current study provides further evidence that PoCT is an acceptable alternative to pathology laboratory testing in a general practice setting. The Bland Altman method is a useful and flexible tool for assessing agreement. Limits of agreement should be reported in future method comparison studies to assist clinicians in patient management.
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Affiliation(s)
- Lisa N Yelland
- Disciplines of Public Health, The University of Adelaide, Adelaide, South Australia, Australia.
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Meurin P, Tabet JY, Monchi M, Weber H, Fabre C, Gibier B, Renaud N, Driss AB. Accuracy of a portable international normalized ratio monitor for patients receiving a low molecular weight heparin as a bridge pending full oral anticoagulant efficacy. Thromb Res 2009; 125:192-5. [PMID: 19942256 DOI: 10.1016/j.thromres.2009.09.004] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2009] [Revised: 07/22/2009] [Accepted: 09/06/2009] [Indexed: 10/20/2022]
Abstract
BACKGROUND Point of care (POC) devices measuring the international normalized ratio (INR) are accurate for patients with stable disease, but their efficiency has not been prospectively assessed during the "bridging period" when patients are receiving a low molecular weight heparin (LMWH) on top of a vitamin K antagonist (VKA) until the target INR is reached. METHODS 188 dual INR measurement using the POC (INR(POC)) and the laboratory (INR(lab)) at the same time were consecutively determined : 69 in patients receiving LMWH+VKA (bridging group) and 119 in patients receiving only a VKA (control group). INRpoc was compared to INR(lab). RESULTS Test strip failure rate was higher in the bridging group than in the control group (29% vs 4%; p<0,001). In successful tests, POC accuracy was not modified by LMWH administration: the correlation coefficients between POC and lab INR values for the bridging group and the control group were 0,81 and 0,87 respectively, and the relative measure of divergence (RMD=INR(lab) - INR(poc)/INR(lab)) was lower in the bridging group than in the control group (4+/-7% vs 10+/-14%; p=0,02). Finally, clinically relevant agreement between POC and laboratory was of 90% in the bridging group and 92.1% in the control group (p=0.6). CONCLUSION With the POC used (INRatio), in patients receiving LMWH when the POC gives a result, it is as accurate as in patients not receiving a LMWH.
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Affiliation(s)
- Ph Meurin
- Les Grands Prés - Centre de réadaptation Cardiaque de la Brie 27 rue Sainte Christine 77174 Villeneuve-Saint-Denis, France.
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Assessment of International Normalized Ratio Using CoaguChek XS and CoaguChek S as Compared With Central Laboratory Testing. POINT OF CARE 2009. [DOI: 10.1097/poc.0b013e3181b32c26] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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Abstract
Since its discovery during the first half of the 20th century by biochemists at the University of Wisconsin, warfarin (along with other vitamin K antagonists) has remained the only oral anticoagulant available to patients at risk for thromboembolism. After nearly 6 decades in clinical practice, we have learned much about warfarin. Although it is highly effective for most patients, warfarin has a number of undesirable attributes: significant inter- and intra-patient variability in dose-response, a narrow therapeutic index, a slow pharmacodynamic response, and numerous interactions with both diet as well as other medications. The negative characteristics associated with warfarin have inspired many clinicians, patients, and researchers to wonder if a better alternative can be discovered. To that end, at least three novel anticoagulant compounds are in the late stages of development and several others are progressing through earlier phases of investigation. This review will summarize the latest clinical trial data pertinent to several newer antithrombotic agents and discuss recent developments that impact the safety and challenges associated with warfarin and other vitamin K antagonists (VKA).
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Affiliation(s)
- David Garcia
- University of New Mexico, Albuquerque, 87131-0001, USA
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Accuracy and clinical usefulness of the CoaguChek S and XS Point of Care devices when starting warfarin in a hospital outreach setting. Thromb Res 2009; 123:909-13. [DOI: 10.1016/j.thromres.2008.10.006] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2008] [Revised: 08/25/2008] [Accepted: 10/20/2008] [Indexed: 11/20/2022]
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Shermock KM, Connor JT, Lavallee DC, Streiff MB. Clinical decision-making as the basis for assessing agreement between measures of the International Normalized Ratio. J Thromb Haemost 2009; 7:87-93. [PMID: 19017256 DOI: 10.1111/j.1538-7836.2008.03225.x] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
Abstract
BACKGROUND The now classic approach of Bland and Altman is often used to assess the level of agreement between International Normalized Ratio (INR) measures. However, we are concerned that this method does not define agreement in a clinically meaningful way. Agreement between measures should be characterized explicitly in terms of clinical decisions that result from INR measures. OBJECTIVES To develop and validate an extension of the Bland-Altman method to assess agreement between INR measures, based explicitly on the way clinicians make decisions. METHODS AND RESULTS We developed a clinically based graphical method to estimate the level of agreement between measures of INR. We identified clinically relevant INR ranges using epidemiologic and clinical evidence regarding risk and expected outcome at different INR ranges. Clinical decisions were expected to agree within these INR ranges and, therefore, the ranges became the basis for establishing agreement between measures. We used paired INR measures and resultant clinical decisions measured during a previous prospective study to validate and compare the accuracy of our model to those of Bland and Altman's and other published models. Our method more accurately predicts when warfarin dosing decisions differ than the Bland-Altman method (P < 0.02). Our method is also superior to other published methods, particularly at the important task of identifying when measures lead to discrepant clinical decisions. CONCLUSIONS We introduced and validated an improvement of the Bland-Altman method to assess agreement between INR measures. Our model is superior because it is based explicitly on factors that influence clinical decision-making.
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Affiliation(s)
- K M Shermock
- Center for Pharmaceutical Outcomes, The Johns Hopkins Medical Institutions, Baltimore, MD, USA.
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Kim SH, Suh SY, Kim HJ, Han SW, Jung SM, Ryu KH. Clinical Utility and Accuracy of Coaguchek® XS, a Reliable Alternative to Laboratory International Normalized Ratio Monitoring in Korean Patients With Atrial Fibrillation. Korean Circ J 2009. [DOI: 10.4070/kcj.2009.39.2.71] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022] Open
Affiliation(s)
- Sung Hea Kim
- Department of Cardiology, Konkuk University School of Medicine, Seoul, Korea
| | - Soon Yong Suh
- Department of Cardiology, Konkuk University School of Medicine, Seoul, Korea
| | - Hyun-Joong Kim
- Department of Cardiology, Konkuk University School of Medicine, Seoul, Korea
| | - Seong Woo Han
- Department of Cardiology, Konkuk University School of Medicine, Seoul, Korea
| | - Sang Man Jung
- Department of Cardiology, Konkuk University School of Medicine, Seoul, Korea
| | - Kyu Hyung Ryu
- Department of Cardiology, Konkuk University School of Medicine, Seoul, Korea
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Ryan F, O'Shea S, Byrne S. The reliability of point-of-care prothrombin time testing. A comparison of CoaguChek S and XS INR measurements with hospital laboratory monitoring. Int J Lab Hematol 2008; 32:e26-33. [PMID: 19032373 DOI: 10.1111/j.1751-553x.2008.01120.x] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
The development of point-of-care (POC) testing devices enables patients to test their own international normalized ratio (INR) at home. However, previous studies have shown that when compared with clinical laboratory values, statistically significant differences may occur between the two methods of INR measurement. The aim of this study was to evaluate the accuracy of the CoaguChek S and XS POC meters relative to clinical laboratory measurements. As part of a randomized, crossover patient self-testing (PST) study at Cork University Hospital, patients were randomized to 6 months PST or 6 months routine care by the anticoagulation management service. During the PST arm of the study, patients measured their INR at home using the CoaguChek S or XS POC meter. External quality control was performed at enrollment, 2 months and 4 months by comparing the POC measured INR with the laboratory determined value. One hundred and fifty-one patients provided 673 paired samples. Good correlation was shown between the two methods of determination (r = 0.91), however, statistically significant differences did occur. A Bland-Altman plot illustrated good agreement of INR values between 2.0 and 3.5 INR units but there was increasing disagreement as the INR rose above 3.5. Eighty-seven per cent of all dual measurements were within the recommended 0.5 INR units of each other. This study adds to the growing evidence that POC testing is a reliable and safe alternative to hospital laboratory monitoring but highlights the importance of external quality control when these devices are used for monitoring oral anticoagulation.
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Affiliation(s)
- F Ryan
- Pharmaceutical Care Research Group, School of Pharmacy, University College Cork, Cork, Ireland
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24
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Bauman ME, Conroy S, Massicotte MP. Point-of-care INR measurement in children requiring warfarin: what has been evaluated and future directions. ACTA ACUST UNITED AC 2008. [DOI: 10.2217/17455111.2.5.651] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Many children are surviving primary illnesses and now require thromboprophylaxis as a result of advances in management. Vitamin K antagonists are commonly prescribed to prevent or treat thrombosis. These agents are far more challenging to effectively manage in children. As a result of these challenges, frequent blood monitoring to measure international normalized ratio (INR) values is required. Point-of-care (POC) INR monitors use a capillary blood sample that has been expressed as a solution to improve effective management of vitamin K antagonist therapy. POC INR meters have been demonstrated to be accurate and precise in measuring INRs. Implementation of a standardized education program prior to patient use of POC meters results in differences between measured laboratory INRs and POC INR comparisons that meet criteria for clinical relevance. This indicates that POC INR meters are safe and effective for use in children.
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Affiliation(s)
- Mary E Bauman
- Stollery Children’s Hospital, University of Alberta, 8440 112 Street, Edmonton, AB, T6G 2B7, Canada
| | - Sherril Conroy
- Faculty of Nursing, University of Alberta, Edmonton, AB, Canada
| | - M Patricia Massicotte
- Stollery Children’s Hospital, University of Alberta, 8440 112 Street, Edmonton, AB, T6G 2B7, Canada
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Ansell J, Hirsh J, Hylek E, Jacobson A, Crowther M, Palareti G. Pharmacology and management of the vitamin K antagonists: American College of Chest Physicians Evidence-Based Clinical Practice Guidelines (8th Edition). Chest 2008; 133:160S-198S. [PMID: 18574265 DOI: 10.1378/chest.08-0670] [Citation(s) in RCA: 1453] [Impact Index Per Article: 90.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
This article concerning the pharmacokinetics and pharmacodynamics of vitamin K antagonists (VKAs) is part of the American College of Chest Physicians Evidence-Based Clinical Practice Guidelines (8th Edition). It describes the antithrombotic effect of the VKAs, the monitoring of anticoagulation intensity, and the clinical applications of VKA therapy and provides specific management recommendations. Grade 1 recommendations are strong and indicate that the benefits do or do not outweigh the risks, burdens, and costs. Grade 2 recommendations suggest that the individual patient's values may lead to different choices. (For a full understanding of the grading, see the "Grades of Recommendation" chapter by Guyatt et al, CHEST 2008; 133:123S-131S.) Among the key recommendations in this article are the following: for dosing of VKAs, we recommend the initiation of oral anticoagulation therapy, with doses between 5 mg and 10 mg for the first 1 or 2 days for most individuals, with subsequent dosing based on the international normalized ratio (INR) response (Grade 1B); we suggest against pharmacogenetic-based dosing until randomized data indicate that it is beneficial (Grade 2C); and in elderly and other patient subgroups who are debilitated or malnourished, we recommend a starting dose of < or = 5 mg (Grade 1C). The article also includes several specific recommendations for the management of patients with nontherapeutic INRs, with INRs above the therapeutic range, and with bleeding whether the INR is therapeutic or elevated. For the use of vitamin K to reverse a mildly elevated INR, we recommend oral rather than subcutaneous administration (Grade 1A). For patients with life-threatening bleeding or intracranial hemorrhage, we recommend the use of prothrombin complex concentrates or recombinant factor VIIa to immediately reverse the INR (Grade 1C). For most patients who have a lupus inhibitor, we recommend a therapeutic target INR of 2.5 (range, 2.0 to 3.0) [Grade 1A]. We recommend that physicians who manage oral anticoagulation therapy do so in a systematic and coordinated fashion, incorporating patient education, systematic INR testing, tracking, follow-up, and good patient communication of results and dose adjustments [Grade 1B]. In patients who are suitably selected and trained, patient self-testing or patient self-management of dosing are effective alternative treatment models that result in improved quality of anticoagulation management, with greater time in the therapeutic range and fewer adverse events. Patient self-monitoring or self-management, however, is a choice made by patients and physicians that depends on many factors. We suggest that such therapeutic management be implemented where suitable (Grade 2B).
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Affiliation(s)
- Jack Ansell
- From Boston University School of Medicine, Boston, MA.
| | - Jack Hirsh
- Hamilton Civic Hospitals, Henderson Research Centre, Hamilton, ON, Canada
| | - Elaine Hylek
- Boston University School of Medicine, Boston, MA
| | | | - Mark Crowther
- McMaster University, St. Joseph's Hospital, Hamilton, ON, Canada
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Laurence C, Gialamas A, Yelland L, Bubner T, Ryan P, Willson K, Glastonbury B, Gill J, Shephard M, Beilby J. A pragmatic cluster randomised controlled trial to evaluate the safety, clinical effectiveness, cost effectiveness and satisfaction with point of care testing in a general practice setting - rationale, design and baseline characteristics. Trials 2008; 9:50. [PMID: 18681979 PMCID: PMC2519057 DOI: 10.1186/1745-6215-9-50] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2008] [Accepted: 08/06/2008] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Point of care testing (PoCT) may be a useful adjunct in the management of chronic conditions in general practice (GP). The provision of pathology test results at the time of the consultation could lead to enhanced clinical management, better health outcomes, greater convenience and satisfaction for patients and general practitioners (GPs), and savings in costs and time. It could also result in inappropriate testing, increased consultations and poor health outcomes resulting from inaccurate results. Currently there are very few randomised controlled trials (RCTs) in GP that have investigated these aspects of PoCT. DESIGN/METHODS The Point of Care Testing in General Practice Trial (PoCT Trial) was an Australian Government funded multi-centre, cluster randomised controlled trial to determine the safety, clinical effectiveness, cost effectiveness and satisfaction of PoCT in a GP setting.The PoCT Trial covered an 18 month period with the intervention consisting of the use of PoCT for seven tests used in the management of patients with diabetes, hyperlipidaemia and patients on anticoagulant therapy. The primary outcome measure was the proportion of patients within target range, a measure of therapeutic control. In addition, the PoCT Trial investigated the safety of PoCT, impact of PoCT on patient compliance to medication, stakeholder satisfaction, cost effectiveness of PoCT versus laboratory testing, and influence of geographic location. DISCUSSION The paper provides an overview of the Trial Design, the rationale for the research methodology chosen and how the Trial was implemented in a GP environment. The evaluation protocol and data collection processes took into account the large number of patients, the broad range of practice types distributed over a large geographic area, and the inclusion of pathology test results from multiple pathology laboratories.The evaluation protocol developed reflects the complexity of the Trial setting, the Trial Design and the approach taken within the funding provided. The PoCT Trial is regarded as a pragmatic RCT, evaluating the effectiveness of implementing PoCT in GP and every effort was made to ensure that, in these circumstances, internal and external validity was maintained. TRIAL REGISTRATION 12612605000272695.
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Affiliation(s)
- Caroline Laurence
- Discipline of General Practice, The University of Adelaide, Adelaide, South Australia, Australia.
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27
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Feasibility, cost-effectiveness and patients’ acceptance of point-of-care INR testing in a hospital-based anticoagulation clinic. Ann Hematol 2008; 87:905-10. [DOI: 10.1007/s00277-008-0530-8] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2007] [Accepted: 06/03/2008] [Indexed: 10/21/2022]
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Braun S, Spannagl M, Völler H. Patient self-testing and self-management of oral anticoagulation. Anal Bioanal Chem 2008; 393:1463-71. [PMID: 18568340 DOI: 10.1007/s00216-008-2225-3] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2008] [Revised: 05/28/2008] [Accepted: 05/30/2008] [Indexed: 11/30/2022]
Abstract
The development of portable instruments for measuring the prothrombin time (PT) in capillary whole blood has made it possible for patients on lifelong coumarin therapy to monitor the effect of the anticoagulant themselves (patient self-testing) and to adjust the dosage if necessary on their own (patient self-management). Dosage variations between individual patients and the narrow therapeutic range of the anticoagulant account for the need to monitor its effect, in order to minimize the risk of thromboembolism resulting from inadequate anticoagulation as well as the risk of bleeding due to overanticoagulation. This review focuses on the prerequisites for the successful implementation of patient self-testing and self-management, such as the selection of eligible patients, appropriate training and the reliability of available instruments. The outcomes of relevant clinical studies involving patient self-testing and self-management are also discussed.
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Affiliation(s)
- Siegmund Braun
- Deutsches Herzzentrum München, Institut für Laboratoriumsmedizin, Lazarettstr. 36, 80636, München, Germany.
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29
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Ansell J, Hirsh J, Hylek E, Jacobson A, Crowther M, Palareti G. Pharmacology and Management of the Vitamin K Antagonists. Chest 2008. [DOI: 10.1378/chest.08-0670 order by 1-- gadu] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/09/2023] Open
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30
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Ansell J, Hirsh J, Hylek E, Jacobson A, Crowther M, Palareti G. Pharmacology and Management of the Vitamin K Antagonists. Chest 2008. [DOI: 10.1378/chest.08-0670 and 1880=1880] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/09/2023] Open
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31
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Ansell J, Hirsh J, Hylek E, Jacobson A, Crowther M, Palareti G. Pharmacology and Management of the Vitamin K Antagonists. Chest 2008. [DOI: 10.1378/chest.08-0670 order by 1-- #] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/09/2023] Open
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32
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Ansell J, Hirsh J, Hylek E, Jacobson A, Crowther M, Palareti G. Pharmacology and Management of the Vitamin K Antagonists. Chest 2008. [DOI: 10.1378/chest.08-0670 order by 8029-- awyx] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/09/2023] Open
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33
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Ansell J, Hirsh J, Hylek E, Jacobson A, Crowther M, Palareti G. Pharmacology and Management of the Vitamin K Antagonists. Chest 2008. [DOI: 10.1378/chest.08-0670 order by 1-- -] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/09/2023] Open
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34
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Ansell J, Hirsh J, Hylek E, Jacobson A, Crowther M, Palareti G. Pharmacology and Management of the Vitamin K Antagonists. Chest 2008. [DOI: 10.1378/chest.08-0670 order by 8029-- #] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/09/2023] Open
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35
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Ansell J, Hirsh J, Hylek E, Jacobson A, Crowther M, Palareti G. Pharmacology and Management of the Vitamin K Antagonists. Chest 2008. [DOI: 10.1378/chest.08-0670 order by 8029-- -] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/09/2023] Open
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36
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Kealey C, Chen Z, Christie J, Thorn CF, Whitehead AS, Price M, Samaha FF, Kimmel SE. Warfarin and cytochrome P450 2C9 genotype: possible ethnic variation in warfarin sensitivity. Pharmacogenomics 2007; 8:217-25. [PMID: 17324110 DOI: 10.2217/14622416.8.3.217] [Citation(s) in RCA: 45] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
INTRODUCTION Warfarin is a widely prescribed, efficacious oral anticoagulant. S-warfarin, the more active form, is metabolized by the cytochrome P450 (CYP)2C9 enzyme. The aim was to evaluate the influence of two CYP2C9 functional polymorphisms (*2 and *3) on warfarin dose in African-Americans, an unstudied population and Caucasians, and also to assess the effect of these polymorphisms on anticoagulation response after accounting for nongenetic factors and genetic factors that might also impact the dose-response relationship of warfarin. PATIENTS AND METHODS A prospective cohort of 362 patients with a target international normalized ratio of between 2.0 and 3.0 were genotyped. Warfarin sensitivity stratified by genotype was investigated using univariate and multivariate analyses. RESULTS The maintenance dose of warfarin was significantly related to genotype (p < 0.01) (variant carriers: 31.25 mg/week; wild-type: 37.5 mg/week), even after adjustment for possible confounding factors (p = 0.046). However, the effect of genotype was restricted to Caucasians, in whom variant carriers had a significantly lower maintenance dose compared with wild-type homozygotes (unadjusted: p < 0.01; adjusted: p = 0.02). There was a greater risk of over-anticoagulation among Caucasian variant carriers, although this was only observed prior to reaching maintenance dose. For African-American variant carriers, there was no difference in warfarin response based on CYP2C9 genotype. DISCUSSION CYP2C9 *2 and *3 variants provide predictive information in anticoagulation response. However, these variants may not be useful in African-Americans or as a marker of long-term over-anticoagulation once a stable dose is reached.
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Affiliation(s)
- Carmel Kealey
- University of Pennsylvania, Department of Pharmacology and Center for Pharmacogenetics, School of Medicine, Philadelphia, PA, USA
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37
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Williams VK, Griffiths AB. Acceptability of CoaguChek S and CoaguChek XS generated international normalised ratios against a laboratory standard in a paediatric setting. Pathology 2007; 39:575-9. [DOI: 10.1080/00313020701684797] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
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38
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Lee JH, Lee KS, Kim DS, Lee HS, Choi SI, Cho YG. Evaluation of CoaguChek® XS for Measuring Prothrombin Time in Patients Receiving Long-term Oral Anticoagulant Therapy. Ann Lab Med 2007; 27:177-81. [DOI: 10.3343/kjlm.2007.27.3.177] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
Affiliation(s)
- Jae Hyeon Lee
- Department of Laboratory Medicine, Chonbuk National University Medical School, Jeonju, Korea
| | - Kyoung Suk Lee
- Division of Cardiology, Internal Medicine (Division of Cardiology), Chonbuk National University Medical School, Jeonju, Korea
- Research Institute of Clinical Medicine, Chonbuk National University, Jeonju, Korea
| | - Dal Sik Kim
- Department of Laboratory Medicine, Chonbuk National University Medical School, Jeonju, Korea
- Research Institute of Clinical Medicine, Chonbuk National University, Jeonju, Korea
| | - Hye Soo Lee
- Department of Laboratory Medicine, Chonbuk National University Medical School, Jeonju, Korea
- Research Institute of Clinical Medicine, Chonbuk National University, Jeonju, Korea
| | - Sam Im Choi
- Department of Laboratory Medicine, Chonbuk National University Medical School, Jeonju, Korea
- Research Institute of Clinical Medicine, Chonbuk National University, Jeonju, Korea
| | - Yong Gon Cho
- Department of Laboratory Medicine, Chonbuk National University Medical School, Jeonju, Korea
- Research Institute of Clinical Medicine, Chonbuk National University, Jeonju, Korea
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Kim JW, Kim MH, Kim KH, Han J, Paik JH, Yu LH, Park TH, Cha KS, Kim YD, Kim KE, Han JY. Comparison between the Portable Prothrombin Time Self Monitor CoaguChek XS and a Standard Laboratory Method, Sysmex CA-1500 for Monitoring Anticoagulant Therapy of Outpatients. Korean Circ J 2007. [DOI: 10.4070/kcj.2007.37.5.216] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022] Open
Affiliation(s)
- Ja Won Kim
- Department of Internal Medicine, College of Medicine, Dong-A University, Busan, Korea
| | - Moo Hyun Kim
- Department of Internal Medicine, College of Medicine, Dong-A University, Busan, Korea
| | - Kyung Ho Kim
- Department of Internal Medicine, College of Medicine, Dong-A University, Busan, Korea
| | - Jin Han
- Department of Internal Medicine, College of Medicine, Dong-A University, Busan, Korea
| | - Jeung Hoan Paik
- Department of Internal Medicine, College of Medicine, Dong-A University, Busan, Korea
| | - Long Hao Yu
- Department of Internal Medicine, College of Medicine, Dong-A University, Busan, Korea
| | - Tae Ho Park
- Department of Internal Medicine, College of Medicine, Dong-A University, Busan, Korea
| | - Kwang Soo Cha
- Department of Internal Medicine, College of Medicine, Dong-A University, Busan, Korea
| | - Young Dae Kim
- Department of Internal Medicine, College of Medicine, Dong-A University, Busan, Korea
| | - Kyung Eun Kim
- Department of Laboratory Medicine, College of Medicine, Dong-A University, Busan, Korea
| | - Jin Yeong Han
- Department of Laboratory Medicine, College of Medicine, Dong-A University, Busan, Korea
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Hentrich DP, Fritschi J, Müller PR, Wuillemin WA. INR comparison between the CoaguChek® S and a standard laboratory method among patients with self-management of oral anticoagulation. Thromb Res 2007; 119:489-95. [PMID: 16765423 DOI: 10.1016/j.thromres.2006.04.003] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2006] [Revised: 03/21/2006] [Accepted: 04/27/2006] [Indexed: 10/24/2022]
Abstract
INTRODUCTION Portable coagulation monitors have been developed to measure International Normalised Ratio (INR) in orally anticoagulated patients using capillary whole blood from a finger stick. Because of unsatisfactory precision of some of the monitors in comparison with laboratory methods new devices are being developed. In the present study we compared INR determination with the CoaguChek S device with a standard laboratory method among patients with self-management of oral anticoagulation (OAC). METHODS Two hundred and forty-two patients performing self-management of OAC were enrolled into this study. Parallel INR measurements were performed within one hour. Capillary INR measurements (INRcap) were done by the patients with the CoaguChek S and venous INR (INRven) by qualified medical staff using a standard laboratory method. RESULTS We found a correlation coefficient (r(S)) of 0.85 (95% CI: 0.81-0.88) among the 242 patients between INRven and INRcap. In 84.4% of the INR parallel measurements the difference between the two values was below 0.5 INR units. In only 2 of 242 cases the difference was >1 INR unit (1.1 and 1.3). The slope of the Passing Bablok regression line was 0.91 (95% CI: 0.83-1.0) and the y-intercept 0.06 (95% CI: -0.20-0.25). Agreement between both methods was 90.5% (95% CI: 86.8-94.2) and standard-agreement even 97.1% (95% CI: 95-99.2). CONCLUSIONS INR measurement with CoaguChek S device by trained patients revealed reliable results in comparison to the values obtained with a standard laboratory method.
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Affiliation(s)
- Dorota Palka Hentrich
- Division of Hematology and Central Hematology Laboratory, Kantonsspital, Lucerne, 6000 Lucerne 16, Switzerland
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41
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Bereznicki LR, Jackson SL, Peterson GM, Jeffrey EC, Marsden KA, Jupe DM. Accuracy and clinical utility of the CoaguChek XS portable international normalised ratio monitor in a pilot study of warfarin home-monitoring. J Clin Pathol 2006; 60:311-4. [PMID: 16751303 PMCID: PMC1860570 DOI: 10.1136/jcp.2006.037820] [Citation(s) in RCA: 50] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
AIM To evaluate the accuracy of the CoaguChek XS international normalised ratio (INR) monitor compared with the laboratory method. METHODS The accuracy and ease of use of the recently marketed CoaguChek XS portable INR monitor was evaluated in 17 patients involved in a trial of warfarin home monitoring. INR results from the monitor were compared with those from the laboratory method. Clinical applicability was measured by discrepant INR values, defined in the literature by expanded and narrow agreement criteria, and by the proportion of INR values differing by >15% and by >20% from those derived by the laboratory method. RESULTS Participants provided 59 comparison INR measurements for analysis. The paired results were highly correlated (r = 0.91). Expanded and narrow agreement between paired INR values occurred 100% of the time. Only three CoaguChek XS (5.1%) results differed by >15% compared with the laboratory method; no results differed by >20% or were discrepant by >0.5 INR units. CONCLUSIONS In the hands of patients the CoaguChek XS showed good correlation with laboratory determination of INR and compared well with expanded and narrow clinical agreement criteria. Both patients and doctors were highly satisfied with the accuracy and ease of use of the CoaguChek XS.
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Affiliation(s)
- Luke R Bereznicki
- Unit for Medication Outcomes Research and Education, School of Pharmacy, University of Tasmania, Hobart, Australia.
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Jackson SL, Peterson GM, Bereznicki LR, Misan GM, Jupe DML, Vial JH. Improving the outcomes of anticoagulation in rural Australia: an evaluation of pharmacist-assisted monitoring of warfarin therapy. J Clin Pharm Ther 2005; 30:345-53. [PMID: 15985048 DOI: 10.1111/j.1365-2710.2005.00656.x] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
OBJECTIVE The aim of this project was to assess whether rural pharmacist involvement in the management of patients receiving warfarin has the potential to lead to safer and more effective anticoagulation, and is valued and welcomed by patients and their general practitioners (GPs). METHODS A convenience sample of rural pharmacists was trained in the use of the CoaguChek S International Normalized Ratio (INR) monitor and then conducted pharmacy-based testing for approximately 3 months. Two types of testing were performed in the pharmacy: (i) comparison testing was defined as pharmacy-based tests taken within 4 h of conventional laboratory testing or (ii) additional testing, which was a pharmacy-based test with no direct comparison laboratory test taken. Pharmacists, GPs and patients completed anonymous satisfaction surveys after the completion of the pharmacy-based testing. RESULTS Pharmacists from 16 rural pharmacies were trained to use the CoaguChek S monitor. During the trial period, 518 INR tests were performed in the pharmacies on 137 different patients. A total of 120 tests were evaluated against results from laboratory testing. The pharmacy-based INR values were significantly correlated with the laboratory INR values (mean of 2.32+/-0.77 and 2.32+/-0.59 respectively; r=0.88, P<0.0001). A total of 398 additional pharmacy-based tests were conducted in the pharmacy and 8.5% of the additional tests resulted in a subsequent dosage change. The monitoring was well received by pharmacists, GPs and patients. CONCLUSIONS The results of the trial were very positive. The CoaguChek S monitor in pharmacy-based testing performed accurately compared with conventional laboratory testing. Further research needs to be conducted on the impact of community pharmacy-conducted INR monitoring on patient care and outcomes.
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Affiliation(s)
- S L Jackson
- School of Pharmacy, University of Tasmania, Hobart, Tas., Australia
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Claes N, Buntinx F, Vijgen J, Arnout J, Vermylen J, Fieuws S, Van Loon H. The Belgian Improvement Study on Oral Anticoagulation Therapy: a randomized clinical trial. Eur Heart J 2005; 26:2159-65. [PMID: 15917280 DOI: 10.1093/eurheartj/ehi327] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
AIMS In Belgium, general practitioners (GPs) mainly manage oral anticoagulation therapy. To improve the quality of oral anticoagulation management by GPs and to compare different models and interventions, a randomized clinical trial was performed. METHODS AND RESULTS Stratified randomization divided 66 GP-practices into four groups. A 6-month retrospective analysis assessed the baseline quality. In the prospective study, each group received education on oral anticoagulation, anticoagulation files, and patient information booklets (groups A, B, C, and D). Group B additionally received feedback every 2 months on their anticoagulation performance; group C determined the international normalized ratio (INR) with a CoaguChek device in the doctor's office or at the patient's home; and group D received Dawn AC computer assisted advice for adapting oral anticoagulation. For the different groups, the time spent in target INR range (Rosendaal's method) and adverse events related to anticoagulation were determined and compared with the same quality indicators at baseline. There was a significant increase in per cent of time within 0.5 INR from target, from 49.5% at baseline to 60% after implementing the different interventions. However, neither the per cent in target range nor the event rates differed among the four groups. CONCLUSION The interventions significantly improved the quality of management of oral anticoagulation by Belgian GPs, mainly as a result of an education and support programme.
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Affiliation(s)
- Neree Claes
- Department of General Practice, Catholic University Leuven, Kapucijnenvoer, 33 Blok J, B-3000 Leuven, Leuven, Belgium.
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Boehlen F, Reber G, de Moerloose P. Agreement of a new whole-blood PT/INR test using capillary samples with plasma INR determinations. Thromb Res 2005; 115:131-4. [PMID: 15567464 DOI: 10.1016/j.thromres.2004.06.023] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2004] [Revised: 06/22/2004] [Accepted: 06/22/2004] [Indexed: 10/26/2022]
Abstract
PURPOSE The objective of the study was to compare in anticoagulated patients the international normalized ratio (INR) measured with a new capillary whole-blood device, the i-STAT Portable Clinical Analyser, with conventional plasma INR obtained from the central laboratory. PATIENTS AND METHODS Between-cartridge variability was first determined with two lyophilized controls with INR levels of 1.60 and 2.75 (n=10). Next, in 35 patients under different intensities of oral anticoagulation, capillary blood INR was measured with two i-STAT devices and was compared to central laboratory plasma INR (Innovin reagent and BCS analyser). RESULTS Between-cartridge coefficients of variation were 5% (95%, CI 3.4-9.1) and 3% (95%, CI 2.1-5.5) at INR levels of 1.60 and 2.75. Mean INR difference between the two i-STAT devices was 0.1, and the correlation coefficient was 0.98. Between i-STAT and central laboratory INR, the correlation coefficient was 0.95. Bias values were 0.04, 0.2, and -0.04 at INR levels of 2.0, 2.5, and 3.5, respectively. CONCLUSION The INR measured with the i-STAT Portable Clinical Analyser is precise and compares well with plasma INR performed in a central laboratory.
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Affiliation(s)
- Françoise Boehlen
- Haemostasis Unit, Department of Medicine, University Hospital, 1211 Geneva 14, Switzerland
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Ansell J, Hirsh J, Poller L, Bussey H, Jacobson A, Hylek E. The pharmacology and management of the vitamin K antagonists: the Seventh ACCP Conference on Antithrombotic and Thrombolytic Therapy. Chest 2004; 126:204S-233S. [PMID: 15383473 DOI: 10.1378/chest.126.3_suppl.204s] [Citation(s) in RCA: 756] [Impact Index Per Article: 37.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
This article concerning the pharmacokinetics and pharmacodynamics of vitamin K antagonists (VKAs) is part of the Seventh American College of Chest Physicians Conference on Antithrombotic and Thrombolytic Therapy: Evidence-Based Guidelines. The article describes the antithrombotic effect of VKAs, the monitoring of anticoagulation intensity, the clinical applications of VKA therapy, and the optimal therapeutic range of VKAs, and provides specific management recommendations. Grade 1 recommendations are strong, and indicate that the benefits do, or do not, outweigh the risks, burdens, and costs. Grade 2 suggests that individual patient's values may lead to different choices (for a full understanding of the grading see Guyatt et al, CHEST 2004; 126:179S-187S). Among the key recommendations in this article are the following: for dosing of VKAs, we suggest the initiation of oral anticoagulation therapy with doses between 5 and 10 mg for the first 1 or 2 days for most individuals, with subsequent dosing based on the international normalized ratio (INR) response (Grade 2B). In the elderly and in other patient subgroups with an elevated bleeding risk, we suggest a starting dose at < or = 5 mg (Grade 2C). We recommend basing subsequent doses after the initial two or three doses on the results of INR monitoring (Grade 1C). The article also includes several specific recommendations for the management of patients with INRs above the therapeutic range and for patients requiring invasive procedures. For example, in patients with mild to moderately elevated INRs without major bleeding, we suggest that when vitamin K is to be given it be administered orally rather than subcutaneously (Grade 1A). For the management of patients with a low risk of thromboembolism, we suggest stopping warfarin therapy approximately 4 days before they undergo surgery (Grade 2C). For patients with a high risk of thromboembolism, we suggest stopping warfarin therapy approximately 4 days before surgery, to allow the INR to return to normal, and beginning therapy with full-dose unfractionated heparin or full-dose low-molecular-weight heparin as the INR falls (Grade 2C). In patients undergoing dental procedures, we suggest the use of tranexamic acid mouthwash (Grade 2B) or epsilon amino caproic acid mouthwash without interrupting anticoagulant therapy (Grade 2B) if there is a concern for local bleeding. For most patients who have a lupus inhibitor, we suggest a therapeutic target INR of 2.5 (range, 2.0 to 3.0) [Grade 2B]. In patients with recurrent thromboembolic events with a therapeutic INR or other additional risk factors, we suggest a target INR of 3.0 (range, 2.5 to 3.5) [Grade 2C]. As models of anticoagulation monitoring and management, we recommend that clinicians incorporate patient education, systematic INR testing, tracking, and follow-up, and good communication with patients concerning results and dosing decisions (Grade 1C+).
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Affiliation(s)
- Jack Ansell
- Department of Medicine, Boston University Medical Center, 88 E Newton St, Boston, MA 02118, USA.
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Jackson SL, Bereznicki LR, Peterson GM, Marsden KA, Jupe DML, Vial JH, Rasiah RL, Misan G, Williams SM. Accuracy and clinical usefulness of the near-patient testing CoaguChek S international normalised ratio monitor in rural medical practice. Aust J Rural Health 2004; 12:137-42. [PMID: 15315540 DOI: 10.1111/j.1440-1854.2004.00585.x] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022] Open
Abstract
OBJECTIVE To compare the accuracy and clinical usefulness of the near-patient testing CoaguChek S INR monitor in rural medical practice. DESIGN, SETTING AND MAIN OUTCOME MEASURES: General practices were identified through Australian university departments of rural health. Study investigators trained general practitioners and/or practice nurses in the use of the CoaguChek S INR monitor. General practices obtained a fingerprick sample for testing with the INR monitor to compare with conventional pathology testing for accuracy. An evaluation questionnaire was administered to users of the machine to assess ease of use and clinical usefulness. RESULTS A total of 169 patients from 15 general practice sites provided 401 paired (CoaguChek S and laboratory) INR results. The CoaguChek S was found to be accurate when compared to laboratory INR (r = 0.89), despite complicating variables such as multiple users of the monitor and multiple laboratories used for comparison with the CoaguChek S INR. Overall, 88% of dual INR measurements were within 0.5 INR units of each other. For laboratory INR </= 1.9, 2.0-3.5 and >/= 3.6, 97%, 90% and 57% of readings were within 0.5 INR units, respectively. Clinical agreement occurred 93% and 90% of the time against published expanded and narrow criteria, respectively. CONCLUSIONS The routine use of near-patient testing, with appropriate training and quality assurance programs, has the potential to increase the safety and efficacy of warfarin therapy in rural and remote communities.
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Affiliation(s)
- Shane L Jackson
- School of Pharmacy, University of Tasmania, Hobart, Tasmania
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Abstract
PURPOSE OF REVIEW The increasing numbers of patients on oral anticoagulants may challenge the traditional organization of patient monitoring. The availability of portable coagulometers capable of measuring prothrombin time (PT) international normalized ratio (INR) in a drop of capillary blood facilitates decentralization of monitoring by self-testing. This article reviews the literature on use of portable coagulometers. RECENT FINDINGS Numerous studies have evaluated the reliability of portable coagulometers in testing the PT-INR. This has been assessed by statistically as well as clinically relevant criteria. Other studies have been devoted to developing calibration models fulfilling the criteria recommended by the World Health Organization (WHO) for the calibration of INR measuring systems. Finally, studies have assessed the value of schemes for patient training and for the long-term quality assurance of portable coagulometers. SUMMARY It can be concluded from the published studies that PT-INR self-testing may be considered as a suitable alternative to conventional laboratory testing. For the PT-INR to be reliable, manufacturers of portable coagulometers should calibrate their devices against international standards for thromboplastin with procedures similar to those recommended by WHO for conventional measuring systems. Training of patients and implementation of appropriate quality assessment schemes are also essential prerequisites for the success of PT-INR self-testing.
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Affiliation(s)
- Armando Tripodi
- Angelo Bianchi Bonomi Hemophilia and Thrombosis Center, Department of Internal Medicine, University and IRCCS Maggiore Hospital, Via Pace 9, 20122 Milan, Italy.
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Taborski U, Völler H, Körtke H, Blunt J, Wegscheider K. Self Management of Oral Anticoagulation with the INRatio System: Accuracy and Reliability Following a Two-Day Structured Training Program. Lab Med 2004. [DOI: 10.1309/jgxchjn1bq71qa40] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022] Open
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Jackson SL, Bereznicki LR, Peterson GM, Marsden KA, Jupe DML, Tegg E, Vial JH, Kimber RI. Accuracy, reproducibility and clinical utility of the CoaguChek S portable international normalized ratio monitor in an outpatient anticoagulation clinic. ACTA ACUST UNITED AC 2004; 26:49-55. [PMID: 14738438 DOI: 10.1111/j.0141-9854.2003.00578.x] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The accuracy and reproducibility of the CoaguChek S, and its clinical agreement with conventional laboratory international normalized ratio (INR) determination, were evaluated in an outpatient anticoagulation clinic setting. Forty-three patients provided 248 paired INR measurements for analysis. The paired results were highly correlated (r = 0.90). The mean coefficient of variation for the CoaguChek S for a random sample of 21 patients with three repeated tests each, was 4%. Clinical applicability was also measured by discrepant INR values, as defined in the literature by expanded and narrow agreement, and by INR values resulting in a different clinical decision by a blinded haematology registrar. Expanded agreement and narrow agreement between the two INR values occurred 90 and 88% of the time, respectively. The stricter criteria set down by the clinician resulted in 73% of paired results producing the same dosage decision. The CoaguChek S displayed good correlation with laboratory determination of INR and compared relatively well with expanded and narrow clinical agreement criteria.
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Affiliation(s)
- S L Jackson
- School of Pharmacy, University of Tasmania, Tasmania, Australia
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Carrasco C, Campbell B, Shiach C. Effects of the lupus anticoagulant on the control of oral anticoagulant treatment. Br J Haematol 2004; 124:562-3. [PMID: 14984514 DOI: 10.1111/j.1365-2141.2004.04813.x] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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