RESUMO
BACKGROUND: Atrial fibrillation (AF) affects 0.5% to 2.0% of the general population and is usually associated with cardiac structural diseases, hemodynamic damage, and thromboembolic complications. Oral anticoagulation prevents thromboembolic events and is monitored by the international normalized ratio (INR). OBJECTIVES: To evaluate INR stability in nonvalvular AF patients treated with warfarin anticoagulation, to evaluate thromboembolic or hemorrhagic complications, and to identify the group at higher risk for thromboembolic or hemorrhagic events. METHODS: Data from the medical records of 203 patients who received medical care at a tertiary hospital in Brazil were reviewed, and the time in therapeutic range (TTR) was calculated using the Rosendaal method. The possible TTR influencing factors were then analyzed, and the relationship between the TTR and thromboembolic or hemorrhagic events was calculated. The level of significance was 5%. RESULTS: The mean TTR was 52.2%. Patients with INR instability in the adaptation phase had a lower mean TTR (46.8%) than those without instability (53.9%). Among the studied patients, 6.9% suffered hemorrhagic events, and 8.4% had a stroke. The higher risk group for stroke and bleeding consisted of patients with INR instability in the adaptation phase. CONCLUSIONS: The quality of anticoagulation in this tertiary hospital in Brazil is similar to that in centers in developing countries. Patients with greater INR instability in the adaptation phase evolved to a lower mean TTR during follow-up, had a 4.94-fold greater chance of stroke, and had a 3.35-fold greater chance of bleeding. Thus, for this patient group, individualizing the choice of anticoagulation therapy would be advised, considering the cost-benefit ratio.
FUNDAMENTO: A fibrilação atrial (FA) afeta de 0,5% a 2,0% da população geral e geralmente está associada a doenças estruturais cardíacas, comprometimento hemodinâmico e complicações tromboembólicas. A anticoagulação oral previne eventos tromboembólicos e é monitorada pela razão normalizada internacional (RNI). OBJETIVOS: Avaliar a estabilidade do RNI em pacientes com FA não valvar tratados com anticoagulante varfarina, avaliar complicações tromboembólicas ou hemorrágicas e identificar o grupo com risco mais alto de eventos tromboembólicos ou hemorrágicos. MÉTODOS: Dados de prontuários médicos de 203 pacientes atendidos em um hospital terciário no Brasil foram analisados e o tempo de intervalo terapêutico (TTR) foi calculado usando-se o método Rosendaal. Em seguida possíveis fatores que influenciam o TTR foram analisados e a relação entre TTR e eventos tromboembólicos ou hemorrágicos foi calculada. O nível de significância foi 5%. RESULTADOS: O TTR médio foi 52,2%. Pacientes com instabilidade de RNI na fase de adaptação tinham um TTR médio mais baixo (46,8%) do que aqueles sem instabilidade (53,9%). Entre os pacientes estudados, 6,9% sofreram eventos hemorrágicos e 8,4% tiveram um acidente vascular cerebral. O grupo com risco mais alto de acidente vascular cerebral e sangramento era composto de pacientes com instabilidade de RNI na fase de adaptação. CONCLUSÕES: A qualidade da anticoagulação nesse hospital terciário no Brasil é semelhante à de centros de países em desenvolvimento. Pacientes com instabilidade de RNI maior na fase de adaptação evoluíram para um TTR médio mais baixo durante o acompanhamento, tinham uma chance de acidente vascular cerebral 4,94 vezes maior e uma chance de sangramento 3,35 vezes maior. Portanto, para esse grupo de pacientes, individualizar a escolha de tratamento anticoagulante seria recomendado, considerando-se a relação custo-benefício.
Assuntos
Fibrilação Atrial , Acidente Vascular Cerebral , Tromboembolia , Anticoagulantes/efeitos adversos , Fibrilação Atrial/complicações , Fibrilação Atrial/tratamento farmacológico , Fibrilação Atrial/epidemiologia , Brasil , Hemorragia/induzido quimicamente , Humanos , Coeficiente Internacional Normatizado/efeitos adversos , Coeficiente Internacional Normatizado/métodos , Acidente Vascular Cerebral/etiologia , Acidente Vascular Cerebral/prevenção & controle , Centros de Atenção Terciária , Resultado do TratamentoRESUMO
INTRODUCTION: The standard of care for thrombotic antiphospholipid syndrome (APS) is anticoagulation with vitamin K antagonists (VKAs). Prothrombin time, and its corresponding international normalized ratio (INR), is the laboratory test routinely performed to assess anticoagulation. Self-management of VKA therapy using point-of-care (POC) devices seems to be an attractive option. PURPOSE/OBJECTIVE: To evaluate the accuracy of a POC device (CoaguChek XS) in APS patients by comparing it with venous laboratory INR. Furthermore, we analyzed whether other clinical and laboratory features could interfere with the CoaguChek XS results. PATIENTS AND METHODS: This is a single-center cross-sectional study with 94 APS patients from a tertiary rheumatology clinic performed from August 2014 to March 2015. The comparison between CoaguChek XS and venous laboratory INR results was evaluated using the coefficient of determination (r) followed by the Bland-Altman test. A paired t-test was also applied. A difference of up to ±0.5 INR unit between the two systems was considered clinically acceptable. RESULTS: The mean CoaguChek-INR was 2.94 ± 1.41 and venous laboratory INR was 2.43±0.86, with a correlation coefficient (r) of 0.95. Categorizing INR values in ranges (INR <2, INR 2-3, INR 3-4, and INR >4), we found that the INR >4 group presented a lower correlation (r = 0.64) compared to the other ranges (p < 0.05). Although both methods were highly correlated, CoaguChek XS showed higher values than the venous laboratory INR, with an increased average of 0.42 ± 0.54. Therefore, we proposed a simple linear regression model to predict the venous laboratory INR values, using results obtained from CoaguChek XS. A difference ≤0.5 INR unit between the two systems was observed in 57.4% of patients, and the aPL profile did not influence the results. CONCLUSION: Although CoaguChek XS and venous laboratory INR demonstrated a good linear correlation in the group of INR ≤4, extra caution should be taken in APS patients, since a reasonable proportion of patients can present differences in INR results that are not acceptable. We do not recommend routine POC in APS patients.
Assuntos
Síndrome Antifosfolipídica , Lúpus Eritematoso Sistêmico , Anticoagulantes/uso terapêutico , Síndrome Antifosfolipídica/diagnóstico , Síndrome Antifosfolipídica/tratamento farmacológico , Estudos Transversais , Monitoramento de Medicamentos/métodos , Humanos , Coeficiente Internacional Normatizado/métodos , Lúpus Eritematoso Sistêmico/tratamento farmacológico , Sistemas Automatizados de Assistência Junto ao Leito , Protrombina , Tempo de Protrombina/métodosRESUMO
OBJECTIVES: To determine whether the generic and branded warfarins used as anticoagulants in Brazil are therapeutic equivalents based on their international normalized ratio (INR) results. METHODS: This crossover randomized controlled trial had four periods. We used the branded Marevan and two generic versions of warfarin sodium tablets, manufactured by União Química and Teuto laboratories, all purchased from retail drugstores. Eligible participants were outpatients from an anticoagulation clinic at a university hospital in São Paulo, Brazil. They had atrial fibrillation or flutter and had been using warfarin for at least 2 months with an INR therapeutic range of 2.0-3.0. Randomization was by numbered, opaque, sealed envelopes. Healthcare personnel and outcome assessors were blinded to treatments, but patients were not. The primary outcome was the variability in the INR (ΔINR) and secondary outcomes included mean INR. We accepted formulations as equivalent if the 95% confidence interval (CI) of the comparison of ΔINR between branded and generic formulations was within the limit of ±0.49. RESULTS: One hundred patients were recruited and randomized to six sequences of treatment (four sequences with n = 17 and two sequences with n = 16). União Química generic warfarin had equivalent variability in the INR to Marevan (ΔINR +0.09 [95% CI -0.29 to +0.46], n = 84). Comparison between Teuto generic warfarin and Marevan was inconclusive (ΔINR +0.29 [95% CI -0.09 to +0.68], n = 84). CONCLUSIONS: Marevan and União Química warfarin had equivalent therapeutic effectiveness and both could be confidently used for anticoagulation. The comparison between Marevan and TW was inconclusive and does not warrant a statement of equivalence. Our methods are especially important for comparing generic and branded drugs that raise concerns and may be subject of future investigations by regulatory agents. TRIAL REGISTRATION: ClinicalTrials.gov NCT02017197.
Assuntos
Fibrilação Atrial/tratamento farmacológico , Coagulação Sanguínea/efeitos dos fármacos , Monitoramento de Medicamentos/métodos , Medicamentos Genéricos/uso terapêutico , Coeficiente Internacional Normatizado/métodos , Varfarina/uso terapêutico , Idoso , Anticoagulantes/uso terapêutico , Fibrilação Atrial/patologia , Brasil , Estudos Cross-Over , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Equivalência Terapêutica , Resultado do TratamentoRESUMO
BACKGROUND & AIMS: The efficacy of fresh frozen plasma (FFP) transfusion in enhancing thrombin generation in patients with cirrhosis and impaired conventional coagulation tests has not been sufficiently explored. Thus, we aimed to assess the effect of FFP transfusion on thrombin generation in these patients. METHODS: Fifty-three consecutive patients receiving a standard dose of FFP to treat bleeding and/or before invasive procedures - if international normalized ratio (INR)/prothrombin time (PT) ratio were ≥1.5 - were prospectively enrolled. The primary endpoint was the amelioration of endogenous thrombin potential (ETP) with thrombomodulin (ETP-TM) after transfusion, which corresponds to the total amount of generated thrombin. INR/PT ratio and activated partial thromboplastin time (aPTT) were also assessed before and after transfusion. RESULTS: FFP enhanced ETP-TM by 5.7%, from 973 (731-1,258) to 1,028 (885-1,343â¯nMâ¯×â¯min; pâ¯=â¯0.019). Before transfusion, evidence of normal or high ETP-TM was found in 94% of patients, even in those with bacterial infections. Only 1 (1.9%) patient had ETP-TM values reverting to the normal range after transfusion. Notably, no patients with low ETP-TM had bleeding. The median decrease in ETP-TM was 8.3% and the mean was 12.8% in 18 (34%) patients after transfusion (from 1,225 [1,071-1,537] to 1,124 [812-1,370] nMâ¯×â¯min; p ≤0.0001). Similar responses to FFP transfusion were observed in patients with compensated and acute decompensated cirrhosis, acute-on-chronic liver failure, infection or shock. FFP significantly ameliorated INR and aPTT values (p <0.0001), but in a minority of patients the values were reduced to less than the cut-off point of 1.5. CONCLUSIONS: FFP transfusion enhanced thrombin generation and ameliorated conventional coagulation tests to normal values in a limited number of patients, and slightly decreased thrombin generation in 34% of cases. LAY SUMMARY: Transfusion of fresh frozen plasma in patients with cirrhosis only slightly improves coagulation test values in a limited number of patients and even appears to worsen them in a third of cases. Transfusion for the purpose of preventing or treating bleeding events could cause inherent risks and costs without clear benefits.
Assuntos
Transtornos da Coagulação Sanguínea/complicações , Transtornos da Coagulação Sanguínea/terapia , Testes de Coagulação Sanguínea/métodos , Transfusão de Componentes Sanguíneos/métodos , Cirrose Hepática/complicações , Cirrose Hepática/terapia , Plasma , Trombina/análise , Trombomodulina/sangue , Insuficiência Hepática Crônica Agudizada/etiologia , Adulto , Infecções Bacterianas/etiologia , Coagulação Sanguínea , Transfusão de Componentes Sanguíneos/efeitos adversos , Feminino , Hemorragia/etiologia , Hemorragia/terapia , Humanos , Coeficiente Internacional Normatizado/métodos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Choque/etiologia , Resultado do TratamentoRESUMO
INTRODUCTION AND AIM: Patients with acute on chronic liver failure (ACLF) have abnormal conventional coagulation tests- platelet count and international normalized ratio (INR). Thromboelastography (TEG) is a rapid, point-of-care assay, more comprehensive than platelet count and INR as it assesses for platelet adequacy (number and function), coagulation factors and clot retraction. The aim of the study was to evaluate the TEG parameters in patients with ACLF, chronic liver disease having acute decompensation (AD) and healthy subjects (HC). MATERIAL AND METHODS: TEG parameters were assessed in patients with ACLF and AD within 24 h of admission. Consecutive patients were included in the study over 12 months. Healthy subjects were recruited as controls. RESULTS: 179 patients were included- 68 ACLF, 53 AD and 58 HC. The mean values of INR in ACLF, AD and HC groups were 2.9 ± 1.4, 1.6 ± 0.4 and 1.1 ± 0.2; P < 0.001. Among TEG parameters - maximum amplitude (MA) was low in ACLF and AD patients as compared with HC (53.8 ± 15, 58.3 ± 13.9 mm and 67.2 ± 12.1 mm, respectively; P < 0.001). Lysis at 30 min (LY30) was high in ACLF patients, as compared to AD and HC (8.6 ± 14.1%, 5.0 ± 9.5% and 4.9 ± 9.8%, respectively; P = 0.060). There were no differences in r time, k time, and alpha angle between groups; normal in >90% patients. There was no difference in TEG parameters between different ACLF grades, whereas CCTs were more deranged with increasing grades of ACLF. CONCLUSION: Despite abnormal conventional coagulation tests, TEG parameters in ACLF patients are essentially normal, except reduced maximum amplitude. Future studies are needed to explore the utility of TEG in clinical management of ACLF patients.
Assuntos
Insuficiência Hepática Crônica Agudizada/diagnóstico por imagem , Insuficiência Hepática Crônica Agudizada/patologia , Tromboelastografia/métodos , Insuficiência Hepática Crônica Agudizada/mortalidade , Adulto , Idoso , Análise de Variância , Coagulação Sanguínea/fisiologia , Estudos de Casos e Controles , Estudos de Coortes , Intervalo Livre de Doença , Feminino , Humanos , Índia , Coeficiente Internacional Normatizado/métodos , Masculino , Pessoa de Meia-Idade , Contagem de Plaquetas , Prognóstico , Valores de Referência , Medição de Risco , Índice de Gravidade de Doença , Taxa de SobrevidaRESUMO
OBJETIVO: Comparar parâmetros clínicos relacionados aos pacientes em uso de varfarina sódica. MÉTODOS: Estudo retrospectivo, cujos dados foram buscados em prontuários e, em seguida, os pacientes foram categorizados em dois grupos: Grupo 1, composto por indivíduos que passaram por consultas nas quais apresentaram ao menos um episódio de valor de Coeficiente Internacional Normatizado (INR) abaixo do limite de normalidade, e Grupo 2, com ao menos uma dosagem de valor de INR acima do limite de normalidade. RESULTADOS: Foram incluídos 73 pacientes que totalizaram 363 consultas em uso de anticoagulante oral, sendo 42 pacientes homens. O intervalo médio entre as consultas foi de 36 dias. Quanto à etnia, a mais prevalente foi a branca, com 56,16%, e a escolaridade mais prevalente foi o primeiro grau completo (72,6%). As doses semanais de varfarina 5mg não diferiram entre as indicações de uso (F=0,218; p=0,953). CONCLUSÃO: Mais da metade das consultas estava fora da faixa terapêutica, demonstrando que a estratégia atual no atendimento clínico-ambulatorial tem suas limitações como o grande intervalo interconsultas e a dificuldade de comunicação com o paciente, seja pelo baixo grau de instrução ou pelo alto fluxo de pacientes. As interações medicamentosas e a interferência do sexo e de comorbidades nos valores de INR devem ser melhores avaliadas em estudos controlados
OBJECTIVE: To compare some clinical parameters related to patients taking warfarin sodium. METHODS: This is a retrospective study, the data of which was collected in medical records, with patients then being categorized into two groups: Group 1, consisting of individuals presenting for consultation who had at least one episode of an International Normalized Ratio (INR) value below the normal range, and Group 2, with at least one dose of INR values above the normal range. RESULTS: The study included 73 patients with a total of 363 visits, on oral anticoagulant therapy, with 42 patients b eing males. The average interval between visits was 36 days. As for ethnicity, the most prevalent was the white one with 56,16%, and the most prevalent educational level was primary school (72.6%). The weekly doses of warfarin 5mg did not differ within the indications of use (F=0.218, p=0.953). CONCLUSION: More than half of the visits were outside therapeutic range, demonstrating that the current strategy in clinical and ambulatory care has its limitations, such as the large interval between consultations, and the difficulty of communication with the patient, either because of the low educational level or the high flow of patients. Drug interactions, the interference of gender, and comorbidities
Assuntos
Humanos , Masculino , Feminino , Assistência Ambulatorial , Anticoagulantes/farmacocinética , Vitamina K/administração & dosagem , Vitamina K/antagonistas & inibidores , Varfarina/administração & dosagem , Coeficiente Internacional Normatizado/métodos , Estudos Retrospectivos , Vitamina K/administração & dosagemRESUMO
BACKGROUND: Medicinal plants (MP) have been used for many years with the purpose of feeding and curing. Several MP may interfere in drug response and are not always considered as potential drug-interactors in clinical practice. OBJECTIVE: To investigate the consumption of MP by outpatients during a one-year follow-up. METHOD: Patients with cardiopathy diagnosis and indication(s) for long-term use of warfarin were recruited at a pharmacist-managed anticoagulation clinic of a Brazilian public hospital. This research employed a descriptive method. The consumption of MP was examined regarding the type, frequency and forms of use. RESULTS: A total of 280 patients were studied. Most patients were female (54.6 %) with an average age of 56.8 ± 13.1 years. The consumption of MP was reported by 46 (16.4 %) patients, totalizing 59 occurrences. Lemon, lemon balm and plantain were the most common MP. The main pharmacological uses involved the digestive, urinary, and respiratory tracts. Tea was the predominant form of consumption (87 %). Twelve (33.3 %) plants presented potential herb-warfarin interactions according to the literature. CONCLUSION: We described the consumption of MP among outpatients characterized by their complex disease status, propensity for adverse events, and socioeconomic limitations. These results may guide pharmacist interventions and procedures to prevent clinical complications.
Assuntos
Anticoagulantes/uso terapêutico , Cardiopatias/tratamento farmacológico , Interações Ervas-Drogas , Ambulatório Hospitalar , Farmacêuticos , Plantas Medicinais , Adulto , Idoso , Brasil/epidemiologia , Feminino , Seguimentos , Cardiopatias/epidemiologia , Humanos , Coeficiente Internacional Normatizado/métodos , Masculino , Pessoa de Meia-Idade , Papel ProfissionalRESUMO
PURPOSE: To analyze the safety of warfarin therapy during cataract surgery under topical anesthesia. METHODS: This was a prospective nonrandomized comparative study of 60 eyes of 60 patients treated with or without concurrent oral warfarin anticoagulant therapy, referred for cataract surgery under topical anesthesia. The sample included a treatment (n=30) and a control (n=30) group. RESULTS: There were no records of intraoperative or postoperative intracameral bleeding complications in both the groups. At 1-month postoperative follow-up, 90.0% of patients presented spectacle-corrected visual acuity of at least 20/40. CONCLUSION: Cataract surgery by phacoemulsification with topical anesthesia can be successfully conducted without discontinuing warfarin.
Assuntos
Anticoagulantes/administração & dosagem , Extração de Catarata/métodos , Varfarina/administração & dosagem , Administração Oral , Anestesia Local , Anestésicos Locais/administração & dosagem , Extração de Catarata/efeitos adversos , Hemorragia Ocular/induzido quimicamente , Seguimentos , Humanos , Coeficiente Internacional Normatizado/métodos , Período Intraoperatório , Implante de Lente Intraocular , Hemorragia Pós-Operatória/induzido quimicamente , Estudos Prospectivos , Acuidade VisualRESUMO
ABSTRACT Purpose: To analyze the safety of warfarin therapy during cataract surgery under topical anesthesia. Methods: This was a prospective nonrandomized comparative study of 60 eyes of 60 patients treated with or without concurrent oral warfarin anticoagulant therapy, referred for cataract surgery under topical anesthesia. The sample included a treatment (n=30) and a control (n=30) group. Results: There were no records of intraoperative or postoperative intracameral bleeding complications in both the groups. At 1-month postoperative follow-up, 90.0% of patients presented spectacle-corrected visual acuity of at least 20/40. Conclusion: Cataract surgery by phacoemulsification with topical anesthesia can be successfully conducted without discontinuing warfarin. .
RESUMO Objetivo: Avaliar a segurança da cirurgia de catarata com anestesia tópica em pacientes em uso de varfarina. Métodos: Estudo comparativo não aleatorizado, prospectivo de 30 olhos de 30 indivíduos sob terapia anticoagulante por via oral com Varfarina que se submeteram à cirurgia de catarata com anestesia tópica. O grupo controle foi composto por 30 olhos de 30 pacientes, com indicação de cirurgia de catarata, que não faziam uso de terapia anticoagulante. Resultados: Não houve registro de complicações hemorrágicas intracamerais transoperatórias ou pós-operatórias em ambos os grupos. Na visita pós-operatória de 30 dias, 90,0% dos pacientes apresentavam acuidade visual corrigida por óculos de pelo menos 20/40. Conclusão: A cirurgia de catarata por facoemulsificação com anestesia tópica pode ser realizada com sucesso sem interrupção da terapia com varfarina. .
Assuntos
Humanos , Anticoagulantes/administração & dosagem , Extração de Catarata/métodos , Varfarina/administração & dosagem , Administração Oral , Anestesia Local , Anestésicos Locais/administração & dosagem , Extração de Catarata/efeitos adversos , Hemorragia Ocular/induzido quimicamente , Seguimentos , Período Intraoperatório , Coeficiente Internacional Normatizado/métodos , Implante de Lente Intraocular , Estudos Prospectivos , Hemorragia Pós-Operatória/induzido quimicamente , Acuidade VisualRESUMO
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.
Assuntos
Anticoagulantes/uso terapêutico , Coeficiente Internacional Normatizado/normas , Sistemas Automatizados de Assistência Junto ao Leito/normas , Terapia Trombolítica , Idoso , Isquemia Encefálica/tratamento farmacológico , Contraindicações , Feminino , Humanos , Coeficiente Internacional Normatizado/métodos , Masculino , Pessoa de Meia-Idade , Valores de Referência , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Estatísticas não Paramétricas , Acidente Vascular Cerebral/tratamento farmacológicoRESUMO
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. .
Valores acima de 1.7 no RNI de pacientes em uso de terapia anticoagulante (ACO) é uma contraindicação para a trombólise no AVC isquêmico. O Objetivo do presente estudo é comparar o teste capilar rápido (TCR) com o exame tradicional de RNI como método de decisão para indicação de terapia trombolítica em pacientes em uso de ACO. Método: Oitenta pacientes em uso crônico de ACO foram submetidos ao TCR e ao exame tradicional durante consulta ambulatorial. Resultados: Ao serem comparados os resultados do TCR com o exame tradicional com o ponto de corte de 1,7 de RNI, o teste rápido teve sensibilidade de 96,6% (IC95% 88,4-99,1) e especificidade de 60,0% (IC95% 38,6-78). O TCR superestimou os níveis de RNI em 0,51 pontos comparado ao exame tradicional. Conclusão: O TCR apresentou elevada sensibilidade, comparado ao exame tradicional para a identificação de pacientes em uso de ACO com indicação de trombólise. .
Assuntos
Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Anticoagulantes/uso terapêutico , Coeficiente Internacional Normatizado/normas , Sistemas Automatizados de Assistência Junto ao Leito/normas , Terapia Trombolítica , Isquemia Encefálica/tratamento farmacológico , Coeficiente Internacional Normatizado/métodos , Valores de Referência , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Estatísticas não Paramétricas , Acidente Vascular Cerebral/tratamento farmacológicoRESUMO
New portable devices for the measurement of the prothrombin time and the international normalized ratio (INR) from capillary blood samples have demonstrated to have good correlation with classic laboratory methods in multiple clinical settings. In this study, we evaluated the performance of the point-of-care device CoaguChek XS (CoaguChek XS; Roche Diagnostics, Basel, Switzerland), comparing the INR results with the standard laboratory method (automatic coagulometer) in an outpatient anticoagulation clinic. Results were compared by linear regression and Bland-Altman plot. Two hundred paired results were collected from 170 patients in a period of 90 days. The main indications for anticoagulation were prophylaxis of venous thromboembolic events, atrial fibrillation and prosthetic heart valves. Mean INR results obtained with the portable device and with the standard laboratory method were 2.22â±â0.70 and 2.30â±â0.77, respectively. The proportion of patients with supratherapeutic INRs was 13.5%. The CoaguChek XS monitor tended to underestimate the INR on average by 0.08âU. The correlation coefficient (R) between the two methods was 0.91 (Pâ<â0.0001). The CoaguChek XS device is suitable for INR monitoring in patients in outpatient oral anticoagulation clinics.
Assuntos
Sistemas Automatizados de Assistência Junto ao Leito , Tempo de Protrombina/métodos , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Anticoagulantes/administração & dosagem , Anticoagulantes/intoxicação , Overdose de Drogas , Humanos , Coeficiente Internacional Normatizado/instrumentação , Coeficiente Internacional Normatizado/métodos , Pessoa de Meia-Idade , Tempo de Protrombina/instrumentação , Varfarina/administração & dosagem , Varfarina/intoxicação , Adulto JovemRESUMO
Background. Monitoring of oral anticoagulant therapy (OAT) is usually accomplished by measuring prothrombin time and the international normalized ratio (INR). However, thromboplastins have different responsiveness and sensitivity to vitamin K-dependent coagulation factors depletion. Several studies have shown INR variation when low sensitive thromboplastins are used. This study compared INR variability between two laboratories using highly sensitive thromboplastins. Methods. A total of 237 plasmas were tested, half of them from patients under OAT. Samples were tested simultaneously in two laboratories: in laboratory A, a Behring Coagulation Timer instrument and a human recombinant thromboplastin (Innovin, Dade Behring) (ISI 1.01) were used. In laboratory B, a Thrombolyzer Compact (Behnk Elektronik) and a rabbit brain thromboplastin (Simplastin Excel S, Organon Teknika) with an ISI of 1.30 were used. Statistical analysis was carried out according to the method of Bland and Altman. Results. Even though high correlation coefficients were obtained when comparing both laboratories, Bland-Altman analysis showed a variation of INR between laboratories ranging from -0.77 to +1.07. After logarithmic transformation of data, these values yielded a variation of the INR either 25% below or 44% above. Conclusions. These results are clearly inadequate for clinical use because such a variation would most probably induce the clinician to make a change in warfarin dose. Standardization of instruments, reagents, and controls is warranted to decrease this variation.
Assuntos
Coeficiente Internacional Normatizado/normas , Anticoagulantes/administração & dosagem , Coagulação Sanguínea/efeitos dos fármacos , Feminino , Humanos , Coeficiente Internacional Normatizado/métodos , Masculino , Tempo de Protrombina , Proteínas Recombinantes/química , Tromboplastina/químicaRESUMO
OBJECTIVE: to compare the international normalized ratio (INR) measured by a point-of-care (POC) testing device with that measured by the conventional method in patients undergoing anticoagulation therapy with warfarin sodium. METHODS: The INR of 383 warfarin-treated patients (mean age: 56.5 years; 207 female) was measured in capillary blood using the Hemochron Jr. device and compared with that of venous plasma samples determined by the conventional method performed in a Coag-A-Mate analyzer. Results were evaluated globally and for the following subgroups: INR < 2.0, from 2.0 to 3.5, and > 3.5. RESULTS: Using both methods, the comparison between INR values yielded a correlation coefficient (r) of 0.86. However, mean differences in INR in both tests, considering the three subgroups, proved to be statistically significant (p <0.001): 0.14 +/- 0.21 (INR< 2.0); 0.54 +/- 0.31 (2.0 < or = INR < or = 3.5), and 1.64 +/- 1.10 (INR> 3.5). Paired Students t-test analysis revealed a p value < 0.001 for the three subgroups studied. CONCLUSION: The use of point-of-care testing for monitoring oral anticoagulation has some limitations. Anticoagulation intensity was underestimated by this method in the three subgroups studied.
Assuntos
Anticoagulantes/uso terapêutico , Coagulação Sanguínea/efeitos dos fármacos , Heparina de Baixo Peso Molecular/uso terapêutico , Coeficiente Internacional Normatizado/métodos , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Tempo de Protrombina , Valores de Referência , Reprodutibilidade dos TestesRESUMO
OBJETIVO: Comparar os resultados do índice de Normalização Internacional (INR) obtidos pelo teste rápido com os do método convencional nos pacientes em terapia de anticoagulação oral com varfarina sódica. MÉTODOS: Para 383 pacientes tratados com varfarina (idade média: 56,5 anos; 207 mulheres), o INR foi determinado em sangue capilar pelo equipamento Hemochron Jr. e comparado com os resultados de amostras de plasma venoso analisadas pelo teste convencional realizado em equipamento Coag-A-Mate. Foram avaliados os resultados do desempenho global das amostras e dos seguintes subgrupos: INR < 2,0, entre 2,0 a 3,5 e > 3,5. RESULTADOS: A comparação entre os valores de INR dos dois métodos resultou em um coeficiente de correlação (r) de 0,86. Entretanto, a análise das diferenças médias entre os resultados dos dois testes, considerando os três subgrupos, apresentou diferenças estatisticamente significativas (p < 0,001): 0,14 ± 0,21 (INR < 2,0); 0,54 ± 0,31 (2,0 < INR < 3,5) e 1,64 ± 1,10 (INR> 3,5). O cálculo do teste t-pareado de Student resultou em um p < 0,001 para os três subgrupos analisados. CONCLUSÃO: A adoção do teste rápido para monitoramento da anticoagulação oral apresenta restrições. Esse método subestimou a intensidade da anticoagulação nos três subgrupos estudados.
OBJECTIVE: to compare the international normalized ratio (INR) measured by a point-of-care (POC) testing device with that measured by the conventional method in patients undergoing anticoagulation therapy with warfarin sodium. METHODS: The INR of 383 warfarin-treated patients (mean age: 56.5 years; 207 female) was measured in capillary blood using the Hemochron Jr. device and compared with that of venous plasma samples determined by the conventional method performed in a Coag-A-Mate analyzer. Results were evaluated globally and for the following subgroups: INR < 2.0, from 2.0 to 3.5, and > 3.5. RESULTS: Using both methods, the comparison between INR values yielded a correlation coefficient (r) of 0.86. However, mean differences in INR in both tests, considering the three subgroups, proved to be statistically significant (p <0.001): 0.14 ± 0.21 (INR< 2.0); 0.54 ± 0.31 (2.0 < INR < 3.5), and 1.64 ± 1.10 (INR> 3.5). Paired StudentÆs t-test analysis revealed a p value < 0.001 for the three subgroups studied. CONCLUSION: The use of point-of-care testing for monitoring oral anticoagulation has some limitations. Anticoagulation intensity was underestimated by this method in the three subgroups studied.