Methylene blue as an adjuvant in volemic resuscitation in the first sixty minutes of hypovolemic shock in pigs

Objetivo: O tratamento precoce do choque hemorrágico é fundamental para prevenir a disfunção orgânica e a morte. Este estudo investigou o uso do azul de metileno (AM) nos primeiros 60 minutos após o choque em um modelo experimental de choque hemorrágico em porcos. Métodos: Após a indução do choque hemorrágico por meio de retirada de volume de sangue suficiente para alcançar um valor de pressão arterial média (PAM) = 55mmHg, os animais (n=30) foram distribuídos aleatoriamente em um dos seis grupos: grupo 1 (60 TS: retransfusão de sangue (TS) após 60 min), grupo 2 (60AM: infusão de AM após 60 min), grupo 3 (60AM+TS: AM e TS após 60 min), grupo 4 (15AM+TS: AM e TS após 15 min), grupo 5 (15TS + 60AM: TS após 15 min e infusão de AM após 60 min), e grupo 6 (15AM + 60TS: infusão de AM após 15 min e TS após 60 min). Foram registrados parâmetros hemodinâmicos e laboratoriais. Resultados: Os maiores valores de PAM máxima/ PAM basal foram alcançados pelos grupos que receberam AM concomitantemente a TS aos 15 e 60 minutos, ou seja, grupos 3 (60AM+TS) e 4 (15AM+TS) e não houve diferença estatística entre eles. Conclusão. O uso de AM em associação com a transfusão sanguínea permitiu a reversão do choque hemorrágico com níveis de pressão arterial média mais altos do que a transfusão apenas ou a combinação de AM e transfusão em momentos diferentes.Objective: Early hemorrhagic shock treatment prevents organic dysfunction and death. This study aimed to investigate the use of methylene blue (MB) in the first sixties minutes after shock in an experimental pig model of hemorrhagic shock. Methods. After shock promotion by blood withdrawal, until reach the mean arterial pressure (MAP) of 55mmHg, animals (n=30) were randomly assigned to one of six groups: group 1 (60 BT: retransfusion (BT) after 60 min), group 2 (60MB: MB infusion after 60 min), group 3 (60MB+BT: MB and BT after 60 min), group 4 (15MB+BT: MB and BT after 15 min), group 5 (15BT + 60MB: BT after 15 min and MB infusion after 60 min), and group 6 (15MB + 60BT: MB infusion after 15 min and BT after 60 min). Hemodynamic and blood tests were collected. Results. The highest values of maximum MAP/basal MAP ratio were achieved by groups that received MB concomitant with BT at the 15th and 60th minutes, that is, groups 3 (60MB+BT) and 4 (15MB+BT), and there was no statistical difference between them. Conclusion. Using MB concomitant with BT allowed the reversal of hemorrhagic shock with higher median arterial pressure levels than BT alone or the combination of MB and BT in different moments

Circulação extracorpórea em adultos no século XXI: ciência, arte ou empirismo? Adult cardiopulmonary bypass in the twentieth century: science, art or empiricism?

A presente revisão tem por objetivo ressaltar alguns aspectos pouco discutidos da circulação extracorpórea (CEC), levando-se em consideração fisiologia, fisiopatologia e algumas novas tecnologias de perfusão. Assim, alguns aspectos, até certo ponto filosóficos, motivaram a elaboração dessa revisão: a) Preservar e atualizar os conhecimentos do cirurgião sobre a CEC, pelo simples fato de manter a sua liderança pedagógica sobre a sua equipe; b) Questionar se pacientes idosos e diabéticos pelas suas características individuais, assim como adotado para crianças, talvez merecessem protocolos mais apropriados; c) Questionar a reação inflamatória sistêmica causada pela exposição do sangue à superfície não endotelizada do circuito de CEC diante da importância crescente do contato do sangue com a ferida cirúrgica; d) Em relação ao tratamento da síndrome vasoplégica, o azul de metileno continua sendo a melhor opção terapêutica, embora, muitas vezes não seja eficiente pela existência de uma "janela terapêutica" embasada na dinâmica da ação da guanilato ciclase (saturação e síntese "de novo") e; finalmente, e) Razão da escolha do título, ressaltando que, em seus moldes atuais, a CEC seria conseqüência do empirismo, arte, ou da ciência? A mensagem final vem com a convicção de que tanto o empirismo, a arte e a ciência são muito fortes em se tratando da CEC.<br>The aim of the present review is to highlight some less discussed aspects of the cardiopulmonary bypass (CPB), taking into consideration the physiology, physiopathology, and some new technologies of perfusion. Thus, some points, to a certain extent philosophical, have motivated this revision: a) To preserve and update the surgeon knowledge regarding CPB, even to keep his/her pedagogical leadership on his/her surgical team; b) To question if elderly and diabetic patients, as a result of their individual characteristics deserve more appropriate protocols similar to those adopted for children; c) One third aspect would be the questioning of the systemic inflammatory reaction caused by the blood exposure to CPB non-endothelized circuit surface, in face of the increasing importance of blood contact with the surgical wound; d) In relation to the treatment of the vasoplegic syndrome, methylene blue continues being the best therapeutical option, even so, many times are not efficient on account of a highly probable existence of a "therapeutical window" based on the guanylate cyclase dynamics of action (saturation and synthesis "de novo") and; finally, e) The reason of the title, highlighting that based on its current patterns, would the CPB be an outcome of empiricism, art, or science? The bottom line of this article carries the certainty of that as much as the empiricism, art, and science are highly related to CPB

Absence of arteriosclerosis in intramyocardial coronary arteries: A mystery to be solved?

Several studies show that portions of intramyocardial coronary arteries are spared of arteriosclerosis, involving morphological, embryological, biochemical and pathophysiological aspects. Endothelial function is significantly affected in the segment of transition, as estimated by the vasoactive response to Ach. These findings suggest that myocardial bridge can provide protection against arteriosclerosis by counteracting the negative effects of endothelial dysfunction. The intramyocardial portion's protection phenomenon deserves further scientific research on all research fronts. Improved morphological, biomechanical and especially physiological and embryological knowledge may be the key to a future window of opportunity for chronic arterial disease therapy and prevention. In addition, this review discusses possible therapeutic approaches for symptomatic coronary ischemia caused by myocardial bridges

Cardiovascular Surgery Residency Program: Training Coronary Anastomosis Using the Arroyo Simulator and UNIFESP Models

ABSTRACT OBJECTIVE: Engage the UNIFESP Cardiovascular Surgery residents in coronary anastomosis, assess their skills and certify results, using the Arroyo Anastomosis Simulator and UNIFESP surgical models. METHODS: First to 6th year residents attended a weekly program of technical training in coronary anastomosis, using 4 simulation models: 1. Arroyo simulator; 2. Dummy with a plastic heart; 3. Dummy with a bovine heart; and 4. Dummy with a beating pig heart. The assessment test was comprised of 10 items, using a scale from 1 to 5 points in each of them, creating a global score of 50 points maximum. RESULTS: The technical performance of the candidate showed improvement in all items, especially manual skill and technical progress, critical sense of the work performed, confidence in the procedure and reduction of the time needed to perform the anastomosis after 12 weeks practice. In response to the multiplicity of factors that currently influence the cardiovascular surgeon training, there have been combined efforts to reform the practices of surgical medical training. CONCLUSION: 1 - The four models of simulators offer a considerable contribution to the field of cardiovascular surgery, improving the skill and dexterity of the surgeon in training. 2 - Residents have shown interest in training and cooperate in the development of innovative procedures for surgical medical training in the art