Which Model Is Better to Teach How to Perform Tube Thoracostomy: Synthetic, Cadaver, or Animal?

INTRODUCTION: The lack of standardized skill training reported by medical students in performing tube thoracostomies may be associated with higher complications. The ideal training model is yet to be determined. This study sought to evaluate three different models. METHODS: Between 2015 and 2017, 204 last-year medical students of Universidade de São Paulo with no prior training in tube thoracostomy were randomized into three groups: cadaver, pig, and synthetic models. All groups performed 1-d tube thoracostomy hands-on training and a 40-min theoretical class. The knowledge acquisition was measured by a comparison between a theoretical test before and 3 wk after the class, and the skills improvement was evaluated by a comparison between the skills test on the same day of the hands-on training and another after 24 wk (the retention skill test). A questionnaire was submitted to evaluate their satisfaction rate and self-reported confidence, as per a Likert scale. RESULTS: The theoretical post-test score was higher compared to the pretest score in all groups (P < 0.001). The retention skills test in the cadaver and synthetic groups decreased compared to the skills test (P = 0.01 and P = 0.007, respectively). There was no difference between the groups either in the theoretical test or in the skills test. Student satisfaction was higher in the cadaver and pig groups. The confidence perception increased in all groups after the training. CONCLUSIONS: The models used for tube thoracostomy training appear to have a similar impact on skills retention, knowledge acquisition, and confidence. Although the satisfaction rate is lower for the synthetic model, it has no biological risk or ethical issues and is more feasible.

N-Acetylcysteine Reduced Ischemia and Reperfusion Damage Associated with Steatohepatitis in Mice.

N-acetylcysteine (NAC) is a pharmacological alternative with great potential for reducing the deleterious effects of surgical procedures on patients with steatohepatitis. We evaluated the effect of NAC on hepatic ischemia/reperfusion (I/R) injury in C57BL/6J mice, 8 weeks-old, weighing 25-30 g, with steatohepatitis induced by a methionine- and choline-deficient (MCD) diet. Groups: MCD group (steatohepatitis), MCD-I/R group (steatohepatitis plus 30 min of 70% liver ischemia and 24 h of reperfusion), MCD-I/R+NAC group (same as MCD-I/R group plus 150 mg/kg NAC 15 min before ischemia), and control group (normal AIN-93M diet). Liver enzymes and histopathology; nitrite and TBARS (thiobarbituric acid reactive substances) levels; pro-inflammatory cytokines; antioxidants enzymes; Nrf2 (nuclear factor erythroid-2-related factor 2) expression; and apoptosis were evaluated. In the group treated with NAC, reductions in inflammatory infiltration; AST (aspartate aminotransferase), nitrite, and TBARS levels; GPx (gutathione peroxidase) activity; cytokines synthesis; and number of apoptotic cells were observed while the GR (glutathione reductase) activity was increased. No differences were observed in Nfr2 expression or in SOD (superoxide dismutase), CAT (catalase), and GST (glutathione S-transferase) activities. Thus, it may be concluded that NAC exerts beneficial effects on mice livers with steatohepatitis submitted to I/R by reducing oxidative stress, inflammatory response, and cell death.

Viabilidade celular da mucosa do intestino delgado de ratos, após correção de choque hipovolêmico com solução de NaCl 7,5%

PURPOSE: Study the effect of the volemic correction with different solutions, in the mucous of the small bowel in rats. METHODS: Were used 120 rats Wistar (Rattus norvegicus albinus), males, adults, seemingly healthy, with individual weight varying between 310 and 410g, originating from of the Instituto Evandro Chagas of Belém of Pará, submitted to an adaptation period of 15 days, receiving water and ration ad libitum, during the role experiment. For the research, ten animals were distributed, in groups and subgroups as following: Standard group (S), Shock group (Sh), Physiological Solution group (PS) and Hypertonic Solution Group (HS). The groups were divided in subgroups with 10 animals each, in agreement with the day of postoperative (DPO) foreseen for the euthanasis of the animals, (1st, 3rd or 7th DPO), being after this, picked material for cellular viability in every animals. RESULTS: The group PS took less quantity viable cells. CONCLUSION: The volemic correction with chloride of sodium solution at 7.5%, when compared the correction with chloride of sodium at 0.9% (isotonic solution), took the maintenance of larger amount of viable cells, in the small bowel in rats.

OBJETIVO: Estudar o efeito da correção volêmica com diferentes tipos de solução, na mucosa do intestino delgado de ratos. MÉTODOS: Foram utilizados 120 ratos Wistar (Rattus norvegicus albinus), machos, adultos, com peso individual entre 310 e 410g, oriundos do Instituto Evandro Chagas de Belém do Pará, submetidos a período de adaptação por 15 dias, recebendo água e ração ad libitum, durante todo o experimento. Os animais foram distribuídos em: Grupo Padrão (P), Grupo Choque (C), Grupo Solução Fisiológica (SF) e Grupo Solução Hipertônica (SH), com 30 animais cada. Estes foram divididos em subgrupos com 10 animais cada, de acordo com o dia de pós-operatório (DPO) previsto para a eutanásia dos animais, (1º, 3º ou 7º DPO), sendo após esta, colhido material para realização de teste de absorvância pelo MTT em todos os animais. RESULTADOS: O grupo SF apresentou menores índices de viabilidade celular comparado aos grupos SH e C (p 0.05). CONCLUSÃO: A correção volêmica com solução de cloreto de sódio a 7.5% levou a manutenção de maior quantidade de células viáveis, no intestino delgado em ratos no 7º dia do experimento.