Avaliação das alterações microcirculatórias secundárias ao uso de ivabradina em um modelo experimental de sepse em hamsters

• Autor(a) principal: Miranda, Marcos Lopes de
• Data de Publicação: 2016
• Tipo de documento: Tese
• Idioma: por
• Título da fonte: Biblioteca Digital de Teses e Dissertações da UERJ
• Texto Completo: http://www.bdtd.uerj.br/handle/1/12570
• topic: Ivabradine; Sepsis; Microcirculation; Ivabradina; Sepse; Microcirculação; Microcirculação; Sepse; CNPQ::CIENCIAS BIOLOGICAS::FISIOLOGIA::FISIOLOGIA DE ORGAOS E SISTEMAS::FISIOLOGIA CARDIOVASCULAR

Ivabradine, an If current inhibitor in the sinoatrial node, has already been used in septic patients although few studies have examined its effects on microcirculatory function. Therefore, we have designed a controlled experimental study to characterize the microcirculatory effects of ivabradine on a murine model of abdominal sepsis that allows in vivo studies of microcirculation. Twenty-eight golden Syrian hamsters were allocated in groups: sham-operated; non-treated septic animals; septic animals treated with saline; septic animals treated with ivabradine (2.0 mg.kg-1 intravenous bolus + 0.5 mg.kg-1.h-1). Intravital microscopy of skinfold chamber preparations allowed quantitative analysis of microvascular variables. Arterial blood pressure, heart rate, activity score, arterial blood gases, and hematological and biochemical parameters were documented. Sepsis decreased capillary perfusion and was associated with organ dysfunction and metabolic acidosis. Ivabradine significantly attenuated these responses: compared with septic animals treated with saline, those treated with ivabradine had less organ dysfunction and higher bicarbonate level (26.7 ± 2.5 vs. 15.7 ± 3.5; p<0.05) and functional capillary density (90.5 ± 4.3% of baseline values vs. 71.0 ± 15.9%; p<0.05) at the end of the experiment. Ivabradine was effective in reducing microvascular derangements evoked by experimental sepsis, which was accompanied by less acidosis and organ dysfunction. These results suggest that ivabradine yields beneficial effects on septic animals microcirculation.