Learning by teaching basic life support: a non-randomized controlled trial with medical students.

BACKGROUND: Cardiopulmonary resuscitation is usually taught in universities through theoretical lectures and simulations on mannequins with low retention of knowledge and skills. New teaching methodologies have been used to improve the learning, placing the student at the center of the process. Likewise, the outside community knows next to nothing about cardiopulmonary resuscitation. Patients who have an out-of-hospital cardiac arrest will die if the effective maneuvers are not promptly done. Learning by teaching could be a way to answer both requirements. It was therefore decided to evaluate whether the medical students' cardiopulmonary resuscitation performance would improve when they teach other people, and if those people could learn with them effectively. METHODS: A non-randomized controlled trial was designed to assess whether teaching Basic Life Support would increase students' learning. Socially engaged, seeking to disseminate knowledge, 92 medical students were trained in Basic Life Support and who subsequently trained 240 community health professionals. The students performed theoretical and practical pre- and post-tests whereas the health professionals performed theoretical pre- and post-tests and one practical test. In order to assess the impact of teaching on students' learning, they were divided into two groups: a case group, with 53 students, reassessed after teaching health professionals, and a control group, with 39 students, reassessed before teaching. RESULTS: The practical students' performance of the case group went from 13.3 ± 2.1 to 15.3 ± 1.2 (maximum = 17, p < 0.001) and theoretical from 10.1 ± 3.0 to 16.4 ± 1.7 (maximum = 20, p < 0.001) while the performance of the control group went from 14.4 ± 1.6 to 14.4 ± 1.4 (p = 0.877) and from 11.2 ± 2.6 to 15.0 ± 2.3 (p < 0.001), respectively. The theoretical performance of the health professionals changed from 7.9 ± 3.6 to 13.3 ± 3.2 (p < 0.001) and the practical performance was 11.7 ± 3.2. CONCLUSIONS: The students who passed through the teaching activity had a theoretical and practical performance superior to that of the control group. The community was able to learn from the students. The study demonstrated that the didactic activity can be an effective methodology of learning, besides allowing the dissemination of knowledge. The University, going beyond its academic boundaries, performs its social responsibility.

Eficácia da confecção de válvulas colônicas após ressecção retoanal em ratos / Efficacy of colonic valves confection after anorectal resection in rats

OBJETIVO: Testar a eficácia da construção de válvulas colônicas após a ressecção retoanal em ratos, para se obter retardo do fluxo intestinal. MÉTODO: Análise clínico-evolutiva, radiológica e anatomopatológica de 31 ratos submetidos a duas seromiotomias circunferenciais transversais no cólon com invaginação sero-serosa e ressecção retoanal, com colostomia perineal. RESULTADOS: Sete ratos morreram no pós-operatório e, necropsiados, apresentavam impactação fecal. Houve redução do peso corporal e fecal no pós-operatório imediato (estatisticamente não significante), seguida de aparente normalização dos valores. Fecalitos aderidos uns aos outros foram freqüentes. Dos 24 animais radiografados, em oito, ao menos uma das válvulas estava visível. Após a necropsia de 21 ratos, constatou-se o predomínio absoluto de fezes a montante das válvulas. Macroscopicamente, nem sempre as válvulas foram identificadas. Na microscopia, encontrou-se hipertrofia das fibras musculares e interrupção da camada muscular com alteração na disposição das fibras e fibrose nos locais da seromiotomia. CONCLUSÕES: A operação foi tecnicamente viável. A presença das fezes a montante das válvulas, a eliminação de fezes aderidas, a hipertrofia e a interrupção da camada muscular reforçam a hipótese de que a seromiotomia age como mecanismo frenador, retardando o trânsito intestinal. O modelo experimental não permite aferir sobre continência fecal.

BACKGROUND: The present study intend to test the efficacy of colonic valves construction after the anorectal resection in rats, in order to obtain retardation of the intestinal flow. METHOD: Clinical, radiological and anatomopathological analysis, ranging from 31 rats, submited to a series of two colonic transversal-circunferential seromiotomies, followed by serous-serous invagination and anorectal resection, and a perineal colostomy. RESULTS: Seven rats have died in the post-operatorium and, when necropsied, they presented faecal impactation. There was reduction in both body and faecal weight in the immediate post-operatorium period (statistically not significant), followed by an apparent normalization of the values. Small stool were found frequently joined together. In eight animals, from twenty-four which underwent radiograph, at least one valve was visible. After the necropsy of 21 rats, there was a major predominance of faeces above the valves. Macroscopically, the valves were not identified quite often. Microscopically, hipertroph in muscle fibers and interruption in muscle lay with alteration in fibers disposition and fibrosis in the places of seromiotomy, were commomly found. CONCLUSIONS: The operation can be considered as being tecnically viable. The presence of faeces above the valves, the elimination of joined stools, the hipertrophy and interruption of muscle layer, all emphasize the hypothesis that seromiotomy acts as a braking mechanism, retarding the intestinal flow. The experimental model adopted does not allow us to make any gauging regarding to faecal continence.

Efeito histológico causado na parede posterior da cavidade abdominal pela lavagem com solução salina 0.9 por cento aquecida a diferentes temperaturas: estudo experimental em ratos / Histological effects caused in the posterior abdominal cavity wall by washing with 0.9 percent saline solutions heated at different temperatures: experimental study in rats

A lavagem da cavidade abdominal com solução salina 0,9 por cento aquecida é uma prática comum em cirurgia geral, mas, geralmente, não há um controle adequado da sua temperatura, sendo por vezes introduzida na cavidade abdominal a temperaturas elevadas, possivelmente causando lesões no nível celular. O objetivo do trabalho é estudar a célula da parede posterior da cavidade abdominal de ratos após o tratamento desta com solução salina 0,9 por cento aquecida a graus diversos. Foram utilizados 28 ratos divididos em três grupos com 9 animais cada e um rato controle. O grupo A foi tratado com solução salina 0,9 por cento a 37ºC, o grupo B a 45ºC e o grupo C a 60ºC. O rato controle não recebeu tratamento com solução salina 0,9 por cento. Em todos os grupos a solução salina 0,9 por cento permaneceu na cavidade durante 1 minuto. Exame histopatológico revelou que no rato controle e nos grupos A e B as fibras musculares e as estriações celulares estavam intactas. No grupo C, no entanto, observaram-se princípios de degeneração celular. Como conclusão ressalta-se a importância de um controle efetivo da temperatura da solução salina 0,9 por cento a ser introduzida na cavidade abdominal de ratos para prevenir um trauma térmico no nível celular.