Compressão intermitente imediata sobre anastomose vascular: Uma nova técnica para prevenir trombose? / Immediate intermittent compression over vascular anastomosis: a new technique to prevent thrombosis

Introdução: Este estudo tem o objetivo de avaliar o efeito da compressão intermitente imediata sobre anastomoses arteriais microcirúrgicas em comparação com compressão fixa e com utilização isolada de irrigação com soro fisiológico e heparina em laboratório experimental. Método: 12 ratos Wistar foram aleatoriamente divididos em três grupos para terem suas artérias femorais seccionas e anastomosadas de forma término-terminal, para comparação de patência com 30 minutos e 7 dias. Grupo I: foi realizada compressão intermitente imediata sobre a anastomose por 60 segundos; grupo II: uma compressão fixa foi mantida imediatamente após a anastomose, também por 60 segundos; grupo III, após o término da anastomose, não foi feita nenhuma intervenção adicional. Além da avaliação da patência, os animais foram pesados e medidos os diâmetros arteriais operados. Resultados: 24 artérias femorais foram abordadas. As médias de peso inicial dos ratos dos grupos I, II e III foram, respectivamente, de 243,8g, 254,6g e 260,4g, enquanto as finais foram de 264,4g, 281g e 282,1g (p<0,001). O diâmetro médio das artérias abordadas foi, respectivamente, de 0,89mm, 0,88mm e 0,90mm, e os tempos de anastomoses em minutos, de 25,6, 24,5 e 24,5, respectivamente; As patências finais após 7 dias foram, respectivamente, de 62,5% (p=0,07), 25% (p=0,48) e 50% (p=0,13). Conclusão: A compressão intermitente imediata pode ser realizada ao término de anastomoses arteriais microcirúrgicos sem prejuízo na patência final do procedimento.

Introduction: This study aims to evaluate the effect of immediate intermittent compression on microsurgical arterial anastomoses in comparison with fixed compression and only observation in an experimental laboratory. Methods: The two femoral arteries of twelve male Wistar rats were sectioned and reanastomosed to compare patency at 30 minutes and 7 days. Group I: immediate intermittent compression was performed over the anastomosis for 60 s; group II: a fixed compression was maintained immediately after the anastomosis for 60 s; group III: after completion of the anastomosis, no additional intervention was performed. In addition to the patency assessment, the animals were weighed and the operated arterial diameters were measured. Results: Twenty-four femoral arteries were examined. Initial average weights of the rats in groups I, II, and III were 243.8g, 254.6g, and 260.4g, respectively, while the final weights were 264.4g, 281g, and 282.1g (p<0.001), respectively; mean diameter of the approached arteries was 0.89, 0.88, and 0.90mm, respectively, and the anastomoses (time in minutes) were 25.6, 24.5, and 24.5, respectively; final patencies after 7 days were 62.5% (p=0.07), 25% (p=0.48), and 50% (p=0.13), respectively. Conclusion: Immediate intermittent compression can be performed at the end of microsurgical arterial anastomoses without affecting the final patency of the procedure.

Clamp vascular de fio de mononylon em microcirurgia experimental / Vascular clamp of mononylon thread in experimental microsurgery

Introdução: A microcirurgia reparadora é ramo hoje indissociável e imprescindível na cirurgia plástica. O treinamento é longo, custo financeiro relativamente alto e exige muito dos proponentes. Para melhorar essa equação a favor da formação de novos microcirurgiões no Brasil, é fundamental facilitar o acesso ao treinamento experimental, utilizando materiais simples. Huaraca descreveu uma técnica utilizando um simples fio mononylon 5-0 para substituir o clamp vascular, que é instrumento indispensável da anastomose microcirúrgica e geralmente de alto custo. O objetivo é comparar a técnica de Huaraca com fio de mononylon e o clamp metálico tradicional durante anastomose microcirúrgica vascular. Métodos: Seis ratos da raça Wistar cujas duas artérias femorais foram aleatoriamente selecionadas para sutura término-terminal após secção completa, sendo um dos lados realizado com clamp vascular habitual e o contralateral com técnica de Huaraca, no mesmo tempo cirúrgico e pelo mesmo cirurgião. Resultados: Em ambas as situações, a taxa de patência foi de 67% após 72 horas, sendo que o tempo médio foi de 26 minutos com a técnica de Huaraca e de 18 minutos com o clamp tradicional (p=0,001). Conclusão: Apesar do tempo de execução mais longo, a técnica de Huaraca é medida simples e de baixo custo que pode substituir o clamp vascular tradicional.

Introduction: Reconstructive microsurgery is now an inseparable and essential branch of plastic surgery. The training is long, has a relatively high financial cost and requires a lot of the proponents. To improve this equation in favor of the formation of new microsurgeons in Brazil, it is essential to facilitate access to experimental training, using simple materials. Huaraca described a technique using a simple 5-0 mononylon thread to replace the vascular clamp, which is an indispensable instrument for microsurgical anastomosis and is generally expensive. The objective is to compare the Huaraca technique with mononylon thread and the traditional metal clamp during vascular microsurgical anastomosis. Methods: Six Wistar rats whose both femoral arteries were randomly selected for end-to-end suture after complete section, with one side performed with usual vascular clamp and the contralateral with Huaraca technique, at the same surgical time and by the same surgeon. Results: In both situations, the patency rate was 67% after 72 hours, with an average time of 26 minutes with the Huaraca technique and 18 minutes with the traditional clamp (p=0.001). Conclusion: Despite the longer execution time, the Huaraca technique is a simple and low-cost measure that can replace the traditional vascular clamp.

Submerged vascular anastomosis. A technique for vascular suturing in experimental microsurgery

ABSTRACT Purpose: To evaluate the impact of submersion of the microsurgical anastomosis suture area using saline (0.9% NaCl) in an experimental laboratory during the training of medical students and resident physicians. Methods: Wistar rats (n = 10) were selected to have the two femoral arteries sectioned and anastomosed end-to-end under optical magnification. They were randomly divided, so that on one side suturing was performed under submersion with saline, and the contralateral side was kept dry during the procedure. The surgical times, as well as the patency within 30 min and 72 h of the procedure, were evaluated. Results: Six male Wistar rats survived the surgical anesthetic procedure, with the average initial weight of 243.3 g and the average artery diameter of 0.86 mm, with average time of 15.67 min for the submerged technique and 20.50 min for the dry technique (p = 0.03). The failure rates were 17 and 50% for the submerged group and the dry one, respectively (p = 0.62). Conclusions: Submerged microvascular suture does not compromise the patency of the vessel or increase the time of anastomosis. Therefore, it is a strategy that can be applied by the surgeon according to his/her technical preferences.