ABSTRACT
A isquemia miocárdica é um importante fator de risco para a mortalidade e eventos cardiovasculares no perioperatório de cirurgias cardíacas e não-cardíacas, sendo que a administração profilática de 'beta'-bloqueadores nesse período, reduz estes riscos. Sabe-se que alterações fisiológicas ocorridas durante a cirurgia de revascularização do miocárdio (RM) com circulação extracorpórea (CEC) podem afetar as concentrações plasmáticas e a cinética de muitos fármacos. Neste estudo, investigou-se a farmacocinética do atenolol em pacientes com angina instável e sem prejuízo renal, submetidos à revascularização com CEC e em terapia crônica com atenolol peroral. O estudo farmacocinético exigiu coleta de amostras sangüíneas seriadas após as doses pré- e pós-operatória. Comparado ao pré-operatório, registrou-se redução não significativa no volume de distribuição e na depuração plasmática após a cirurgia, permanecendo inalterada a meia-vida biológica (p>0,05). Uma correlação linear negativa entre meia-vida e depuração pode ser estabelecida nos dois períodos do estudo (r: -0,77, p= 0,06 no pré-operatório e r: -0,89, p= 0,06 no pós-operatório), enquanto que se estimou correlação linear direta entre volume de distribuição e meia-vida biológica apenas no pré-cirúrgico (r: 0,54, p= 0,03 no pré-operatório e r: 0,09, p= 0,03 no pós-operatório). Conclui-se que a cirurgia de revascularização auxilia no restabelecimento da extensão da distribuição do atenolol
Myocardium ischemia is an important factor of risk for mortality and cardiovascular events in the perioperative period of cardiac and non cardiac surgeries. However, the prophylactic administration of b-blocker agents could reduce these risks. Physiologic changes, occurred during the coronary artery bypass graft (CABG) surgery with cardiopulmonary bypass (CPB), could alter plasma concentration and pharmacokinetics of many drugs. This study investigated the pharmacokinetics of atenolol in patients with unstable angina and without renal dysfunction, submitted to CABG surgery and treated chronically with atenolol PO. For pharmacokinetic analysis, 13 blood samples were collected after doses administrated pre- and post-operatively. Compared to the pre-operative period, it was verified a non-significant reduction in the apparent volume of distribution and plasma clearance after the surgery, remaining unchanged the biological half-life, p>0.05 (NS). A negative linear correlation between plasma clearance and elimination half-life was demonstrated in both periods of the study (r: -0.77 p=0.06, pre-surgery and r: -0.89, p=0.06, post-surgery), while a correlation between volume of distribution and biological half-life was established only before revascularization (r: 0,54 p= 0,03 , pre-surgery and r: 0,09, p=0,03, post-surgery). We suggest that the CABG surgery leads to the normalization of the extension of distribution of atenolol
Subject(s)
Humans , Male , Middle Aged , Angina, Unstable/metabolism , Atenolol/pharmacokinetics , Myocardial Revascularization , Myocardial Ischemia , Returning StateABSTRACT
This study was designed to examine the relationship between pericardial fluid and plasma CRP levels, and to alterations in other biochemical parameters in patients undergoing Coronary Artery Bypass Grafting (CABG). The study group consisted of 96 Coronary Artery Disease (CAD) patients who were referred to our clinic for a CABG procedure and from whom sufficient amount of pericardial fluid could be collected. The patients were classified into 3 groups: Stable Angina Pectoris (SAP) (n=27), Unstable Angina Pectoris (USAP) (n=36), and Post-Myocardial Infarction (PMI) (n=33). Levels of CRP, glucose, albumin, total protein, Creatine Kinase (CK), Creatine Kinase-MB (CK-MB), and Lactate Dehydrogenase (LDH) were determined in pericardial fluid samples and in simultaneously collected blood samples from radial artery. The pericardial CRP and LDH levels in the PMI group were higher than in the SAP (p=0.015 and p=0.000, respectively) and USAP (p=0.011, p=0.047) groups. Serum CRP levels in USAP (p=0.014) and PMI (p= 0.000) groups were higher than those in the SAP group. Pericardial albumin levels in the PMI group were higher than in the USAP group (p=0.038). In all groups, the pericardial fluid/serum protein ratio was > 0.5, the LDL ratio was > 0.6, and pericardial fluid LDH concentrations were > 300mg/dl. CRP level of pericardial fluid was significantly higher in the PMI group than in other groups. However, pericardial fluid LDH levels were higher than blood LDH levels in this group and were also higher than pericardial fluid LDH levels of other groups.
Subject(s)
Middle Aged , Male , Humans , Female , Aged , Pericardial Effusion/metabolism , Myocardial Infarction/metabolism , Coronary Artery Bypass , C-Reactive Protein/metabolism , Biomarkers , Angina, Unstable/metabolismABSTRACT
This study was designed to examine the relationship between pericardial fluid and plasma CRP levels, and to alterations in other biochemical parameters in patients undergoing Coronary Artery Bypass Grafting (CABG). The study group consisted of 96 Coronary Artery Disease (CAD) patients who were referred to our clinic for a CABG procedure and from whom sufficient amount of pericardial fluid could be collected. The patients were classified into 3 groups: Stable Angina Pectoris (SAP) (n=27), Unstable Angina Pectoris (USAP) (n=36), and Post-Myocardial Infarction (PMI) (n=33). Levels of CRP, glucose, albumin, total protein, Creatine Kinase (CK), Creatine Kinase-MB (CK-MB), and Lactate Dehydrogenase (LDH) were determined in pericardial fluid samples and in simultaneously collected blood samples from radial artery. The pericardial CRP and LDH levels in the PMI group were higher than in the SAP (p=0.015 and p=0.000, respectively) and USAP (p=0.011, p=0.047) groups. Serum CRP levels in USAP (p=0.014) and PMI (p= 0.000) groups were higher than those in the SAP group. Pericardial albumin levels in the PMI group were higher than in the USAP group (p=0.038). In all groups, the pericardial fluid/serum protein ratio was > 0.5, the LDL ratio was > 0.6, and pericardial fluid LDH concentrations were > 300mg/dl. CRP level of pericardial fluid was significantly higher in the PMI group than in other groups. However, pericardial fluid LDH levels were higher than blood LDH levels in this group and were also higher than pericardial fluid LDH levels of other groups.
Subject(s)
Middle Aged , Male , Humans , Female , Aged , Pericardial Effusion/metabolism , Myocardial Infarction/metabolism , Coronary Artery Bypass , C-Reactive Protein/metabolism , Biomarkers , Angina, Unstable/metabolismABSTRACT
O objetivo do trabalho foi obter comprimidos de liberação controlada não desintegráveis contendo o bloqueador ßi-adrenéergico, tartarato de metoprolol, empregando-se carboximetilcelulose 1-5000cps (CMC), hidroxipropilmetilcelulose 100.000cps (Methocel© K100), polímeros metacrilatos (Eudragit© NE30D e RS30D), etilcelulose (Ethocel© 10 e 100cps) e ácido esteárico como modificadores da liberação. Os comprimidos foram submetidos a testes de dissolução em meio gástrico e intestinal, simulado sem enzimas, conforme a Farmacopéia Americana 24 ed. (aparelho 2), e por variação de pH para avaliação dos perfis e cinéticas de dissolução. Os comprimidos produzidos com polímeros hidrofílicos (CMC, Methocel©) hidrataram-se rapidamente com a liberação do fármaco, sendo controlado pela difusão através da matriz intumescida e gelificada...