Does CO2 pneumoperitoneum in laparoscopy interfere with collagen deposition in abdominal surgical wounds?

Abstract Purpose To determine by histomorphometric analysis whether CO2 pneumoperitoneum interferes with collagen deposition in surgical wounds in the aponeurosis of rats. Methods This experiment involved 80 male Wistar rats, randomly allocated into four groups according to pneumoperitoneum period (PRE: 30 min preoperatively; POST: 30 min postoperatively; PP: 30 min pre- and postoperatively; C: control group). CO2 pneumoperitoneum was insufflated to 5 mmHg of pressure. A laparotomy was performed; 1 cm of the left colon was then resected, and an end-to-end anastomosis was performed to simulate surgical trauma, after which the abdominal wall was closed. On postoperative days 7 or 14, a sample of the abdominal wall was collected, stained with picrosirius red and observed under polarized light in an optical microscope. The amount of collagen was estimated by computerized histomorphometric analysis. Results There were no significant differences in collagen deposition between the control and experimental groups on postoperative days 7 (p=0.720) or 14 (p=0.933). The amount of collagen increased as expected in all groups between postoperative days 7 and 14 (p=0.0003). Conclusion At 5 mmHg, CO2 pneumoperitoneum does not interfere with collagen deposition in abdominal wall surgical wounds in rats.

The effect of carbon dioxide pneumoperitoneum on the healing colonic anastomosis in rats

PURPOSE: To investigate the effects of pneumoperitoneum on colonic anastomosis healing. METHODS: Colonic anastomosis was performed in 120 rats divided into four groups: Group I - pneumoperitoneum before laparotomy, Group II - pneumoperitoneum after laparorrhaphy, Group III - pneumoperitoneum before laparotomy and after laparorrhaphy, Group IV - no pneumoperitoneum (control group). Pneumoperitoneum pressure was 5 mmHg. Animals were killed on the 3rd, 7th and 14th postoperative day. Hhistopathological features, anastomosis breaking strength, collagen histomorphometry and hydroxyproline concentration were assessed. RESULTS: Breaking strength between groups: (day 3, p=0.165; day 7, p=0.219; day 14, p=0.539). Histopathology revealed that group II had, on day 7, less infiltration of mononuclear cells (p=0.006), greater infiltration of polymorphonuclear cells (p=0.001) and greater necrosis (p=0.001); and on day 14, less fibrosis. Histomorphometry revealed a decrease in collagen in groups I and III (p<0.001) on day 7 and an increase in groups I and II on day 14 (p<0.001). Hydroxyproline concentration was similar for groups on days 3 (p=0.152), 7 (p=0.913) or 14 (p=0.981). CONCLUSION: Carbon dioxide does not impair the healing of colonic anastomosis in rats.

The effect of carbon dioxide therapy on composite graft survival

PURPOSE: To investigate the effect of carboxytherapy in auricular composite grafts in rabbits. METHODS: An experimental study was conducted using 20 rabbits randomly assigned to a treatment group of carboxytherapy or a control group of saline solution. In each ear, a circular graft with 1.5 cm or 2 cm of diameter was amputated and reattached. Animals underwent carbon dioxide or saline injection four times during the experiment. We analyzed clinical evolution of the animals, grafts survival, histopathology features and histomorphometry of collagen. RESULTS:The treated group had a significantly lower weight gain (p=0.038). Histopathology was not significantly different between groups. There was an increase in amount of collagen in 2 cm grafts submitted to carbon dioxide therapy (p=0.003). Carboxytherapy didn't influence graft survival rate for 1.5 cm grafts or 2 cm grafts (p=0.567 and p=0.777, respectively). CONCLUSIONS:Carbon dioxide therapy increased the amount of collagen in 2 cm grafts. CO2 was not significantly different from saline infusion on composite grafts survival, but this study suggests that there is a mechanical effect caused by distension which favored graft survival.

Correlation between bursting pressure and breaking strength in colonic anastomosis

PURPOSE: To investigate the correlation between bursting pressure and breaking strength on the 7th postoperative day following left colonic anastomosis in rats. METHODS: Seventy rats were randomly divided into seven groups of ten animals each. All of the animals underwent segmental resection of the left colon and end-to-end anastomosis. The animals in groups I to VI underwent surgical laparoscopies with pneumoperitoneums using carbon dioxide or helium at pressures of 5, 12 or 20 mmHg. In Group VII, open laparotomy was performed. The animals were reoperated on postoperative day 7 to measure the bursting pressure and the breaking strength of the anastomosis. RESULTS: The anastomosis bursting pressure in 70 animals was 193.10±55.56 mmHg. There was no significant difference between the groups (p=0.786). The breaking strength of the anastomosis was 0.26±0.12 N. There was no significant difference between the groups (p=0.356). Pearson's correlation test showed a low correlation (r=0.231) lacking statistical significance (p=0.054). CONCLUSION: There was no correlation between the bursting pressure and breaking strength of left colonic anastomoses in rats on the 7th postoperative day.

A new proposal for laparoscopic left colectomy in a rat model

PURPOSE: To evaluate the feasibility and safety of a new technique for laparoscopic segmental colectomy and primary anastomosis in the left colon of rats. METHODS: Thirty rats were randomly assigned to three groups of ten animals each. All animals underwent segmental resection of the left colon and end-to-end anastomosis. In Group I, the animals underwent laparoscopic surgery with carbon dioxide pneumoperitoneum at a pressure of 5 mmHg. In Group II, the animals underwent pneumoperitoneum with carbon dioxide at a pressure of 12 mmHg. In Group III, the control group, the animals underwent open surgery. All animals were reopened on the 7th postoperative day and were evaluated for peritonitis, abscesses, anastomotic dehiscence and bowel obstruction, and the anastomosis bursting pressure was measured. RESULTS: No obstructions, peritonitis or abscesses were found in any of the animals. An animal in Group I exhibited a blocked anastomosis leakage. The average anastomosis bursting pressure in the 30 animals was 187.02 ± 68.35 mmHg. There was no significant difference in the anastomosis bursting pressure among the groups (p = 0.503) CONCLUSION: The laparoscopic experimental model was feasible and safe for segmental colectomy and anastomosis of the left colon in rats.

Laparoscopic training in colorectal surgery: can we do it safely? / Colectomia videolaparoscópica: é seguro treinar o residente?

OBJECTIVE: Laparoscopic approach should be offered for most patients requiring colectomy, as it is a safe procedure, associated with shorter hospitalization, better cosmetic results, and does not affect negatively the oncological outcomes of patients with colon cancer. However, there is no consistent data on the safety of laparoscopic surgery training during residency. Therefore, the aim of this study was to assess whether or not the resident participation in laparoscopic colectomy affected the postoperative outcomes. METHODS: The database of the American College of Surgeons National Surgical Quality Improvement Program (ACS-NSQIP) was searched for patients undergoing laparoscopic colectomies between 2005 and 2007. We excluded patients with no data regarding whether or not there was a resident participation in the operation. The study population was divided into 2 groups (resident and nonresident), according to residents participation in the surgical procedure. Perioperative variables and postoperative complications were compared between groups. A multivariate analysis was performed to evaluate the association between postoperative complications and resident participation in the operation. RESULTS: The search yielded 5,912 patients with a median age of 63 years. Of these, 3,112 (53%) were female and 3.887 (66%) had a resident involved in their operation. The resident group had a significantly longer mean operative time (163 ± 64 min vs 138 ± 58 min, p < 0.0001). Other variables did not differ significantly between groups. Moreover, multivariate analysis showed no association between resident participation and the occurrence of postoperative complications. CONCLUSION: Laparoscopic training during residency may be safely performed without threatening the patient's integrity. (AU)

OBJETIVO: Cirurgia videolaparoscópica é a via preferencial para colectomias eletivas por ser um procedimento seguro, associado à menor tempo de internação, melhores resultados estéticos e por não influenciar negativamente os resultados oncológicos dos pacientes com câncer de cólon. Entretanto, ainda não existem dados consistentes sobre a segurança do treinamento em cirurgia laparoscópica durante a residência. Sendo assim, o objetivo deste estudo foi avaliar se a participação do residente em colectomias laparoscópicas afetou os resultados pós-operatórios. MÉTODOS: A base de dados do American College of Surgeons National Surgical Quality Improvement Program (ACS-NSQIP) foi pesquisada para colectomias laparoscópicas entre os anos de 2005 e 2007. A população do estudo foi dividida em dois grupos de acordo com a participação ou não do residente na cirurgia: residente vs. não residente. Os grupos foram comparados em relação às variáveis perioperatórias e complicações pós-operatórias. Uma análise multivariada foi realizada para investigar possível associação entre complicações pós-operatórias e o envolvimento de residentes na operação. A pesquisa retornou 5.912 pacientes, com mediana de idade de 63 anos. Em 3.887 casos (66%) o residente estava envolvido na operação. O grupo Residente apresentou tempo operatório mediano significantemente maior que o grupo Não Residente (163 ± 64 min vs. 138 ± 58 min, p < 0.0001). Todas as outras variáveis estudadas não diferiram significativamente entre os grupos. Além disso, a análise multivariada não demonstrou nenhuma associação entre o envolvimento do residente na operação e a ocorrência de complicações pós-operatórias. CONCLUSÃO: O treinamento laparoscópico durante a residência pode ser realizado com segurança sem colocar em risco a integridade do paciente operado. (AU)

Evaluation of the effects of carbon dioxide pneumoperitoneum on abdominal wall wound healing in rats undergoing segmental resection and anastomosis of the left colon / Avaliação dos efeitos do pneumoperitônio com dióxido de carbono na cicatrização da parede abdominal de ratos submetidos à ressecção segmentar e anastomose no cólon esquerdo

PURPOSE: To evaluate the influence of carbon dioxide pneumoperitoneum on abdominal wall wound healing in rats. METHODS: Eighty rats underwent laparotomy, segmental left colon resection, and anastomosis. The animals were divided into three experimental groups and one control group: EI = pneumoperitoneum for 30 minutes before laparotomy (n=20); EII = pneumoperitoneum for 30 minutes after abdominal closure (n=20); EIII = pneumoperitoneum for 30 minutes before laparotomy and 30 minutes after abdominal closure (n=20); C = control group, without pneumoperitoneum (n=20). In each group, 10 animals were killed 7 days and 10 animals 14 days postoperatively. A segment of the abdominal wall was resected and subjected to tensile strength testing. Another segment of abdominal muscle was used for histopathological analysis; the specimens were fixed in formalin and stained with hematoxylin and eosin. RESULTS: There were no differences in histopathology and tensile strength values among animals in the experimental and control groups 7 or 14 days after surgery. CONCLUSION: Under the present experimental conditions, carbon dioxide pneumoperitoneum did not interfere with abdominal wall wound healing.

OBJETIVO: Avaliar a influência do pneumoperitônio com dióxido de carbono na cicatrização da ferida operatória na parede abdominal de ratos. MÉTODOS: Oitenta ratos foram submetidos à laparotomia, ressecção de segmento do cólon esquerdo e anastomose. Os animais foram distribuídos em quatro grupos de 20 ratos, três experimentais e um controle: Grupo EI = pneumoperitônio por 30 minutos antes da laparotomia. Grupo EII = pneumoperitônio por 30 minutos após a laparorrafia. Grupo EIII = pneumoperitônio por 30 minutos antes da laparotomia e 30 após a laparorrafia. Grupo C = controle, sem pneumoperitônio. Realizou-se, em cada grupo, a eutanásia de 10 animais no 7° e no 14° dia pós-operatório. Um segmento da parede abdominal foi ressecado e submetido à medida da resistência. Outro segmento muscular abdominal foi destinado à análise histopatológica, as peças foram fixadas em formol e as lâminas coradas com hematoxilina e eosina. RESULTADOS: Não houve diferença, à histopatologia e na força de ruptura, entre os animais dos grupos experimentais e do controle no 7° ou 14° dia pós-operatório. CONCLUSÃO: Nas condições em que o experimento foi realizado, o pneumoperitônio com dióxido de carbono não interferiu na cicatrização da parede abdominal.

Effects of carbon dioxide pneumoperitoneum on hepatic and renal morphology of rats after segmental colectomy and colonic anastomosis / Efeitos do pneumoperitônio com dióxido de carbono sobre a morfologia renal e hepática de ratos submetidos à colectomia segmentar e anastomose colônica

PURPOSE: To evaluate the effects of increased intraperitoneal pressure caused by carbon dioxide pneumoperitoneum on the hepatic and renal morphology of rats. METHODS: Fifty-four adult male rats were randomly divided into three groups (P, PP and C) after anesthesia: P - in 18 animals, pneumoperitoneum was established for 30 minutes immediately before laparotomy; PP - in 18 animals, pneumoperitoneum was established for 60 minutes divided into 30 immediately before laparotomy and 30 after abdominal closure; control group (C) - 18 animals underwent laparotomy without pneumoperitoneum induction. The pneumoperitoneum was maintained at a pressure of 5 mm Hg. Nine animals in each group were killed on the 3rd and 7th postoperative days, when kidney and liver samples were collected for morphological analysis. The liver specimens were stained with hematoxylin and eosin (HE), and the kidney specimens, with HE and von Kossa. Blinded examiners analyzed the slides. RESULTS: No changes in renal morphology were found. Liver samples showed histological signs of degeneration in animals in the pneumoperitoneum groups killed on the 7th postoperative day (p=0.029). CONCLUSION: The CO2 pneumoperitoneum did not affect renal morphology but caused hydropic degeneration in the liver of animals killed on the 7th postoperative day.

OBJETIVO: Avaliar os efeitos do aumento de pressão intraperitonial causada pelo pneumoperitônio com dióxido de carbono na morfologia renal e hepática de ratos submetidos à colectomia segmentar a anastomose colônica. MÉTODOS: 54 ratos machos da linhagem Winstar, que, após serem anestesiados, foram aleatoriamente distribuídos em três grupos (P, PP e C): P - 18 animais submetidos a pneumoperitônio por 30 minutos imediatamente antes da laparotomia PP - 18 animais submetidos a pneumoperitônio por 60 minutos, 30 imediatamente antes da laparotomia e 30 após a laparorrafia ; C - (grupo controle) - 18 animais submetidos à laparotomia sem o uso de pneumoperitônio. Os animais foram mortos no terceiro e sétimo dia pós-operatório, quando ocorreu a coleta do rim e parte do fígado. As peças foram coradas com Hematoxilina e Eosina e Von Kossa e analisadas por um patologista que desconhecia os grupos. RESULTADOS: Não foram observadas alterações nas estruturas renais. Nas amostras hepáticas foram observados achados histológicos como a degeneração hidrópica no grupo de animais mortos no sétimo DPO (p= 0,029). CONCLUSÃO: O pneumoperitônio com dióxido de carbono não afetou a morfologia renal e causou a degeneração hidrópica no fígado dos animais mortos no 7º dia pós-operatório.

Câncer anal e doenças sexualmente transmissíveis: qual a correlação? / Anal cancer and sexually transmitted diseases: what is the correlation?

OBJETIVO: O Câncer Anal é um tumor raro, cuja incidência é influenciada pelo comportamento sexual. O objetivo do trabalho é verificar a correlação entre o Câncer Anal e as Doenças Sexualmente Transmissíveis, como HPV, HIV, Infecção Gonocócica, Infecção por Clamídia, Sífilis e outras. MÉTODOS: Foram pesquisadas no site do Datasus as internações por Câncer Anal, HPV, HIV, Infecção Gonocócica, Infecção por Clamídia, Sífilis e outras DSTs, no SUS no Brasil, entre 1998 e 2007. O teste de correlação de Pearson foi aplicado. RESULTADOS: Há uma correlação positiva muito alta entre as internações por Câncer Anal e HPV (r = 0,98, p<0,001). Há uma correlação negativa entre as internações por Câncer Anal e as internações por Infecção Gonocócica (r = -0,81, p=0,005) e Infecção por Clamídia (r = -0,74, p=0,014). Não houve correlação estatisticamente significante entre Câncer Anal e as internações por HIV (r = 0,40, p=0,245), outras DSTs (r = 0,55, p=0,1) e Sífilis (r = -0,61, p=0,059). CONCLUSÃO: Há uma correlação positiva muito alta entre as internações por Câncer Anal e HPV no Brasil. Há uma correlação negativa entre as internações por Câncer Anal, Infecção Gonocócica e Infecção por Clamídia.

OBJECTIVE: Anal Cancer is a rare tumor, which incidence is influenced by sexual behavior. The purpose of this paper is to verify the correlation between Anal Cancer and Sexually Transmitted Diseases, such as HPV, HIV, Gonococci Infection, Chlamydia Infection, Syphilis and others. METHODS: All the internments due to Anal Cancer, HIV, HPV, Syphilis, Gonococci Infection, Chlamydia Infection and other Sexually Transmitted Diseases in public healthy in Brazil were collected at Datasus site between 1998 and 2007. The Pearson correlation test was done. RESULTS: There was a high correlation between Anal Cancer and HPV admissions (r=0,98, p<0,001). There was negative correlation between Anal Cancer and Gonococci Infection admissions (r=-0,81, p=0,005) and Anal Cancer and Chlamydia Infection (r=-0,74, p=0,014). There was not statistic significant correlation between Anal Cancer and HIV admissions (r=0,40, p=0,245), between Anal Cancer and other Sexually Transmitted Diseases (r=0,55, p=0,1), and between Anal Cancer and Syphilis (r=-0,61, p=0,059). CONCLUSION: There was a high positive correlation between Anal Cancer and HPV admissions in Brazil. There were negative correlations between Anal Cancer and Gonococci Infection and between Anal Cancer and Chlamydia Infection admissions.