Nível de informação e adesão à terapia de anticoagulação oral com varfarina em pacientes acompanhados em ambulatório de atenção primária à saúde / Knowledge and information levels and adherence to oral anticoagulant therapy with warfarin in patients attending primary health care services

A anticoagulação oral com varfarina é usada por milhões de pacientes em todo o mundo, apresentando segurança e eficácia bem estabelecidas. Ainda assim, na atenção primária à saúde, os anticoagulantes estão entre as classes de medicamentos mais associadas a erros de medicação fatais. Objetivo: Verificar o nível de informação e a adesão ao tratamento com varfarina em pacientes acompanhados em ambulatório de atenção primária à saúde. Método: Foi realizado um estudo transversal de uma coorte prospectiva com 60 pacientes em uso de varfarina no município de Ijuí, Rio Grande do Sul. Utilizou-se questionário para verificar o nível de informações dos usuários quanto à prescrição e o nível das informações prestadas pela equipe de saúde aos usuários. A Escala de Adesão Terapêutica de Morisky de Oito Itens (MMAS-8) e o coeficiente internacional normatizado ( international normalized ratio , INR) foram usados para verificar a adesão ao tratamento. Resultados: Os resultados foram expressos em valores absolutos e relativos e razão de prevalência, com seu respectivo intervalo de confiança de 95%. Verificou-se que 83,3% dos participantes tiveram nível de informação insuficiente prestada pela equipe de saúde, 50,0% não souberam informar sobre o uso correto do medicamento, 86,7% foram não aderentes ao tratamento segundo a MMAS-8, e 63,3% estavam fora do intervalo terapêutico adequado. Conclusão: Neste estudo, observou-se a necessidade de melhorar a qualidade das informações prestadas aos usuários e criar estratégias para adesão ao tratamento, visando à segurança do paciente em tratamento com varfarina na atenção primária à saúde.

Oral anticoagulation therapy with warfarin is widely used around the world and its safety and efficacy are well-established. Nevertheless, anticoagulants are among the drug classes most associated with fatal medication errors in primary health care. Objective: To investigate patient knowledge, the level of information provided, and medication adherence in patients treated with warfarin at a primary health care service. Method: A cross-sectional study of a prospective cohort of 60 patients on warfarin treatment in the town of Ijuí, Rio Grande do Sul, Brazil. A questionnaire was administered to test patients' knowledge about their prescriptions and the level of information provided by the health team. The 8-item Morisky Medication Adherence Scale (MMAS-8) and International Normalized Ratio (INR) were used to verify adherence to treatment. Results: The results were expressed in absolute and relative values and prevalence ratios were calculated, with respective 95% confidence intervals. It was found that 83.3% of the participants had been given insufficient information by the health team, 50% did not know how to use the medication correctly, 86.7% were not adherent to the treatment according to MMAS-8 and 63.3% were outside of the correct INR range. Conclusion: In this study, we observed a need to improve the quality of information provided to users and to develop strategies to improve adherence to treatment, to ensure the safety of patients treated with warfarin in primary health care services.

Reversal of the anticoagulant and anti-hemostatic effect of low molecular weight heparin by direct prothrombin activation

Lopap, found in the bristles of Lonomia obliqua caterpillar, is the first exogenous prothrombin activator that shows serine protease-like activity, independent of prothrombinase components and unique lipocalin reported to interfere with hemostasis mechanisms. To assess the action of an exogenous prothrombin activator reversing the anticoagulant and antihemostatic effect induced by low molecular weight heparin (LMWH), male New Zealand rabbits (N = 20, weighing 3.8-4.0 kg) allocated to 4 groups were anticoagulated with 1800 IU/kg LMWH (iv) over 2 min, followed by iv administration of saline (SG) or recombinant Lopap (rLopap) at 1 µg/kg (LG1) or 10 µg/kg (LG10), 10 min after the injection of LMWH, in a blind manner. Control animals (CG) were treated only with saline. The action of rLopap was assessed in terms of activated partial thromboplastin time (aPTT), prothrombin fragment F1+2, fibrinogen, and ear puncture bleeding time (BT) at 5, 10, 15, 17, 20, 30, 40, 60, and 90 min after initiation of LMWH infusion. LG10 animals showed a decrease of aPTT in more than 50% and BT near to normal baseline. The level of prothrombin fragment F1+2 measured by ELISA had a 6-fold increase with rLopap treatment (10 µg/kg) and was inversely proportional to BT in LMWH-treated animals. Thus, Lopap, obtained in recombinant form using E. coli expression system, was useful in antagonizing the effect of LMWH through direct prothrombin activation, which can be a possible strategy for the reversal of bleeding and anticoagulant events.

Controle laboratorial da anticoagulaçäo oral / Laboratory control of the oral anticoagulation

Objetivo. Foram testadas seis preparaçöes de tromboplastina na realizaçäo do controle laboratorial da anticoagulaçäo oral. Material e Métodos. Os reagentes testados foram: Labtest, lote n§ 0301, ISI = 1,50; Biolab, lote n§ 10252, ISI = 1,60; Baxter TPCD, lote n§ 502A, ISI = 2,55; Baxter TPC, lote n§ 13, ISI = 1,97; Baxter TPS, lote n§ 27, ISI = 1,18; e Behring, lote n§ 505771A, ISI = 1,11. Foram avaliados 31 pacientes portadores de doença tromboembólica, em uso da mesma dose de drogas antivitamina K há mais de dez dias, mediante medida do tempo de protrombina (TP). Para cada reagente foi construída curva-padräo, utilizando-se pool de plasmas normais diluído em tampäo Veronal. Os resultados obtidos em segundos foram expressos em atividade de protrombina (AP), deduzindo-se o valor na curva-padräo. Foram também expressos em RNI, calculada a partir do resultado do TP para cada paciente, e do índice de sensibilidade internacional (ISI) de cada preparaçäo de tromboplastina, fornecido pelo fabricante. Resultados. Existe discrepância entre os resultados obtidos com preparaçöes diferentes, quando se expressa o resultado em AP (p < 0,01), mas esta discrepância desaparece ao se exprimi-lo em RNI. Conclusöes. Demonstra-se a necessidade de se exprimir o resultado do TP em RNI quando do controle laboratorial das drogas antivitamina K, permitindo o ajuste de dose do medicamento com segurança, sem interferência das variaçöes de sensibilidade dos reagentes utilizados por vários laboratórios

Cytoprotective effect of dilazep on hydrogen peroxide-perturbed vascular endothelial cells.

The effect of dilazep and dimethyl thiourea (DMTU) on the hydrogen peroxide-derived injury of culture pulmonary artery epithelial cells (CPAEC) was assessed by colorimetric assay of MTT formazan (MTT formazan assay). When CPAEC were treated with hydrogen peroxide, neither cell lysis nor detachment of the cells from surface of the well was observed. However, the MTT formazan formation was decreased in a time and dose dependent manner. The decrease in the formation was significantly suppressed in the presence of dilazep (0.1 to 10 microM) or DMTU (0.01 to 0.3 microM). CPAEC treated with hydrogen peroxide in the same way enhanced an activation of prothrombin, and this enhancement was significantly inhibited in the presence of dilazep (1 to 3 microM). These data indicate that dilazep exerts a cytoprotective effect against challenges of intracellular oxidant produced by hydrogen peroxide and suppresses augmented procoagulant activity of injured cells.