Avaliação hemodinâmica em oclusões vasculares do membro posterior de ratos
Data
2022-11-17
Autores
Moura, Sayonê Andrade de {UNIFESP]
Orientadores
Koh, Ivan Hong Jun [UNIFESP]
Tipo
Dissertação de mestrado
Título da Revista
ISSN da Revista
Título de Volume
Resumo
O restabelecimento do fluxo sanguíneo arterial macrovascular em pacientes portadores da doença arterial obstrutiva crônica (DAOP) melhora as taxas de cicatrização de feridas, dor em repouso e diminui a necessidade de amputações em cerca de 70-90% dos casos. No entanto, 10-15% dos pacientes portadores de DAOP não obtêm melhora. Estes fatos demandam o estudo da interrelação hemodinâmica entre os componentes macrovasculares arteriais e venosos com a microcirculação e a perfusão e viabilidade tecidual em DAOP. Objetivo: Estudar a cinética da macro e microhemodinâmica em oclusões vasculares em membro posterior de ratos. Métodos: Foram utilizados 85 animais ratos Wistar-EPM fêmeas, entre 3 e 4 meses de idade, de 200g a 300g, distribuídos em Grupo Naive (GN) e três grupos de oclusões vasculares: GA (oclusão arterial), GV (oclusão venosa) GAV (oclusão arterial e venosa), na artéria femoral comum, veia femoral comum e artéria e veia femorais comuns, respectivamente, do membro posterior esquerdo. Todos os animais foram submetidos a análise da macrocirculação quanto ao volume de fluxo com probes perivasculares, perfusão tecidual (TPU) pelo Laser Doppler e a avaliação microcirculatória pelo Sidestream Dark Field Imaging (SDF). As avaliações foram nos tempos T60’(minutos), T7d, T30d e T90d (dias) após as oclusões vasculares. Resultados: Após as oclusões vasculares, houve redução do fluxo macrovascular sem recuperação completa ao longo dos 90 dias. A recuperação da perfusão tecidual e da densidade microcirculatória ocorreu sem a recuperação completa macrovascular. Conclusões: 1. As oclusões vasculares, tanto arterial, venosa ou combinadas, promoveram um estado de hipofluxo macrocirculatório, com recuperação parcial ao longo do tempo de 3 meses; 2. O processo de restabelecimento da dinâmica microcirculatória foi parcialmente dependente das adaptações da macrocirculação em todos os tipos de oclusão, sugerindo um mecanismo próprio de adaptação da rede microcirculatória. 3. O impacto do hipofluxo macrovascular na dinâmica da adaptação microcirculatória variou segundo o tipo de oclusão.
Restoration of macrovascular arterial blood flow in patients with chronic obstructive arterial disease (COPD) improves wound healing rates, pain at rest, and decreases the need for amputations in about 70-90% of cases. However, 10-15% of patients with PAOD do not improve. These facts demand the study of the hemodynamic interrelationship between the arterial and venous macrovascular components with the microcirculation and tissue perfusion and viability in PAOD. Objective: To study the kinetics of macro and microhemodynamics in vascular occlusions in the hind limbs of rats. Methods: Eighty-five female Wistar-EPM rats were used, aged between 3 and 4 months, weighing 200g to 300g, and divided into Naive Group (GN) and three vascular occlusion groups: GA (arterial occlusion), GV (venous occlusion), and GAV (arterial and venous occlusion), in the common femoral artery, common femoral vein, and common femoral artery and vein, respectively, of the left hind limb. All animals were submitted to macrocirculatory analysis for flow volume with perivascular probes, tissue perfusion (TPU) by Laser Doppler and microcirculatory evaluation by Sidestream Dark Field Imaging (SDF). Assessments were made at times T60' (minutes), T7d, T30d, and T90d (days) after vascular occlusions. Results: After vascular occlusions, there was a reduction in macrovascular flow without complete recovery over 90 days. Recovery of tissue perfusion and microcirculatory density occurred without complete macrovascular recovery. Conclusions: 1. Vascular occlusions, whether arterial, venous or combined, promoted a state of macrocirculatory hypoflow, with partial recovery over a period of 3 months; 2. The process of restoring the microcirculatory dynamics was partially dependent on the adaptations of the macrocirculation in all types of occlusion, suggesting an adaptation mechanism of the microcirculatory network. 3. The impact of macrovascular hypoflow on the dynamics of microcirculatory adaptation varied according to the type of occlusion.
Restoration of macrovascular arterial blood flow in patients with chronic obstructive arterial disease (COPD) improves wound healing rates, pain at rest, and decreases the need for amputations in about 70-90% of cases. However, 10-15% of patients with PAOD do not improve. These facts demand the study of the hemodynamic interrelationship between the arterial and venous macrovascular components with the microcirculation and tissue perfusion and viability in PAOD. Objective: To study the kinetics of macro and microhemodynamics in vascular occlusions in the hind limbs of rats. Methods: Eighty-five female Wistar-EPM rats were used, aged between 3 and 4 months, weighing 200g to 300g, and divided into Naive Group (GN) and three vascular occlusion groups: GA (arterial occlusion), GV (venous occlusion), and GAV (arterial and venous occlusion), in the common femoral artery, common femoral vein, and common femoral artery and vein, respectively, of the left hind limb. All animals were submitted to macrocirculatory analysis for flow volume with perivascular probes, tissue perfusion (TPU) by Laser Doppler and microcirculatory evaluation by Sidestream Dark Field Imaging (SDF). Assessments were made at times T60' (minutes), T7d, T30d, and T90d (days) after vascular occlusions. Results: After vascular occlusions, there was a reduction in macrovascular flow without complete recovery over 90 days. Recovery of tissue perfusion and microcirculatory density occurred without complete macrovascular recovery. Conclusions: 1. Vascular occlusions, whether arterial, venous or combined, promoted a state of macrocirculatory hypoflow, with partial recovery over a period of 3 months; 2. The process of restoring the microcirculatory dynamics was partially dependent on the adaptations of the macrocirculation in all types of occlusion, suggesting an adaptation mechanism of the microcirculatory network. 3. The impact of macrovascular hypoflow on the dynamics of microcirculatory adaptation varied according to the type of occlusion.