Effect of preconditioning and postoperative hyperbaric oxygen therapy on colonic anastomosis healing with and without ischemia in rats

Abstract Purpose To investigate the effect of hyperbaric oxygen therapy on colonic anastomosis healing with and without ischemia in rats. Methods Forty female rats underwent segmental resection of 1 cm of the left colon followed by end-to-end anastomosis. They were randomly assigned to four groups (n=10 each), a sham group; two groups were submitted to Hyperbaric Oxygen therapy (HBOT) with and without induced ischemia and the induced ischemia group without HBOT. The HBOT protocol evaluated was 100% O2 at 2.4 Atmosphere absolute pressure (ATA) for 60 minutes, two sessions before as a preconditioning protocol and three sessions after the operation. Clinical course and mortality were monitored during all experiment and on the day of euthanasia on the fourth day after laparotomy. Macroscopic appearance of the abdominal cavity were assessed and samples for breaking strength of the anastomosis and histopathological parameters were collected. Results There was no statistically significant difference in mortality or anastomosis leak between the four experimental groups. Anastomosis breaking strength was similar across groups. Conclusion The HBOT protocol tested herein at 2.4 ATA did not affect histopathological and biomechanical parameters of colonic anastomotic healing, neither the clinical outcomes death and anastomosis leak on the fourth day after laparotomy.

Faringo-íleo-colo anastomosis con suplemento vascular microquirúrgico en reconstrucción del tracto digestivo superior / Pharyngo-ileo-colo-anastomosis with micro-vascular blood supply augmentation for surgical reconstruction of the upper digestive tract

Resumen Introducción Los pacientes sometidos a desconexión total con cierre al nivel del seno piriforme debido a necrosis completa del esófago y estómago después de la ingestión cáustica representan un desafío quirúrgico para restablecer la ingestión oral y la calidad de vida. Objetivo El objetivo de este trabajo es presentar la experiencia con un caso clínico con necrosis total de esófago y estómago posingestión de cáuticos por lo que fue inicialmente sometido a esofagectomía y gastrectomía total. Método La reconstrucción del tracto digestivo superior se efectuó mediante una faringo-íleo-colo anastomosis, con suplemento de irrigación sanguínea arterial y drenaje venoso mediante técnica de anastomosis microquirúrgica. Resultados No se observaron complicaciones postoperatorias mayores y en el resultado a largo plazo se logra alimentación oral normal con una recuperación nutricional adecuada y buena calidad de vida. Conclusión Esta es un procedimiento a plantear en pacientes con estenosis faríngea sin posibilidad de reemplazo esofágico con procedimientos menos complejos.

Introduction Patients submitted to total esophagectomy and gastrectomy with complete closure of pharinx due to necrosis after caustic ingestion are a challenging surgical setting for reconstruction of upper digestive transit. Objective The objective of this paper is to present a clinical case and surgical technique for reconstruction of the upper digestive tract after total esophagectomy and gastrectomy. Method Reconstruction of digestive transit was reestablished by means of a pharyngo-ileo-colonic interposition with microsurgical arterial and venous anastomosis for augmentation of blood supply. Results There were not major postoperative complications and at long term follow-up, normal oral nutrition and quality of life improvement was observed. Conclusion This is a surgical procedure for treatment of patients with pharyngeal strictures without any possibility to indicate other less complex procedures.

Fluorescent test accurately predicts leak of ischemic colon anastomosis in rats

Abstract Purpose: To investigate if fluorescein fluorescent test can predict dehiscence in a model of ischemic colonic anastomosis in rats. Methods: This experimental controlled trial randomly assigned 55 rats to four groups. Anastomoses were performed in non-ischemic colon segments (control group) and in ischemic colon segments measuring 1, 2 or 3 cm long (groups 1, 2 and 3, respectively). Fluorescein was injected and the tissues were examined under ultraviolet light. Seven days later, a second-look surgery was performed to check for the presence or absence of anastomosis dehiscence. Results: Twenty-four rats presented anastomotic dehiscence during the second-look surgery. Reticular and nonfluorescent patterns were significantly associated with the occurrence of anastomotic dehiscence. Fluorescein fluorescence had a sensitivity of 95.8%, specificity of 89.2%, positive predictive value of 88.4%, negative predictive value of 96.2%, and accuracy of 92.3% to predict anastomotic dehiscence. Conclusion: Fluorescein fluorescent test can accurately predict leak in a model of ischemic colonic anastomosis in rats.

Vascular Map Combined with CT Colonography for Evaluating Candidates for Laparoscopic Colorectal Surgery

Contrast-enhanced computed tomography colonography (CE-CTC) is a useful guide for the laparoscopic surgeon to avoid incorrectly removing the colonic segment and the failure to diagnose of synchronous colonic and extra-colonic lesions. Lymph node dissection and vessel ligation under a laparoscopic approach can be time-consuming and can damage vessels and organs. Moreover, mesenteric vessels have extreme variations in terms of their courses and numbers. We describe the benefit of using an abdominal vascular map created by CE-CTC in laparoscopic colorectal surgery candidates. We describe patients with different diseases (colorectal cancer, diverticular disease, and inflammatory bowel disease) who underwent CE-CTC just prior to laparoscopic surgery.

Effects of maternal ischemic preconditioning in the colon of newborn rats submitted to hypoxia-reoxygenation insult

PURPOSE: To evaluate the effects of maternal remote ischemic preconditioning (IPCr) in the colonic mucosa of newborn rats subjected to hypoxia and reoxygenation. METHODS: Newborn Wistar rats were divided into three groups. Control Group (CG), Hypoxia and Reoxygenation Group (HRG) and Remote Ischemic Preconditioning Group (IPCrG). Hypoxia and reoxygenation was performed 2x per day, with an interval of 6 hours, on the 1st, 2nd and 3rd days of life, with 10 minutes of CO2 at 100%, followed by 10 minutes O2 at 100%(HRG/IPCrG). The maternal IPCr was performed 24 hours before delivery by applying a rubber band tourniquet to the left hind limb (IPCrG). Segments of the colon underwent histological (HE) and immunohistochemical analysis for caspase-3 and COX - 2. RESULTS: The histological findings showed no intestinal mucosal damage in the CG group and severe lesions in HRG that was attenuated in the IPCrG (p<0.05). The expression of the apoptotic cells was lower in the HRG group than in the CG and IPCrG. The COX-2 expression was intense in HRG and attenuated in the IPCrG (p<0.05). CONCLUSIONS: Maternal IPCr protected the colonic mucosa of newborn rats subjected to hypoxia and reoxygenation, reducing the morphological alterations and inflammatory response. It ameliorates the occurrence of apoptosis, keeping the physiological process of renewal and regeneration in the epithelial lining of the colonic mucosa. .

Fibrinogen and thrombin concentrations are critical for fibrin glue adherence in rat high-risk colon anastomoses

OBJECTIVE: Fibrin glues have not been consistently successful in preventing the dehiscence of high-risk colonic anastomoses. Fibrinogen and thrombin concentrations in glues determine their ability to function as sealants, healers, and/or adhesives. The objective of the current study was to compare the effects of different concentrations of fibrinogen and thrombin on bursting pressure, leaks, dehiscence, and morphology of high-risk ischemic colonic anastomoses using fibrin glue in rats. METHODS: Colonic anastomoses in adult female Sprague-Dawley rats (weight, 250-350 g) treated with fibrin glue containing different concentrations of fibrinogen and thrombin were evaluated at post-operative day 5. The interventions were low-risk (normal) or high-risk (ischemic) end-to-end colonic anastomoses using polypropylene sutures and topical application of fibrinogen at high (120 mg/mL) or low (40 mg/mL) concentrations and thrombin at high (1000 IU/mL) or low (500 IU/mL) concentrations. RESULTS: Ischemia alone, anastomosis alone, or both together reduced the bursting pressure. Glues containing a low fibrinogen concentration improved this parameter in all cases. High thrombin in combination with low fibrinogen also improved adherence exclusively in low-risk anastomoses. No differences were detected with respect to macroscopic parameters, histopathology, or hydroxyproline content at 5 days post-anastomosis. CONCLUSIONS: Fibrin glue with a low fibrinogen content normalizes the bursting pressure of high-risk ischemic left-colon anastomoses in rats at day 5 after surgery. .

Is combined therapy more effective than growth hormone or hyperbaric oxygen alone in the healing of left ischemic and non-ischemic colonic anastomoses?

OBJECTIVE: Our aim was to investigate the effects of growth hormone (GH), hyperbaric oxygen and combined therapy on normal and ischemic colonic anastomoses in rats. METHODS: Eighty male Wistar rats were divided into eight groups (n = 10). In the first four groups, non-ischemic colonic anastomosis was performed, whereas in the remaining four groups, ischemic colonic anastomosis was performed. In groups 5, 6, 7, and 8, colonic ischemia was established by ligating 2 cm of the mesocolon on either side of the anastomosis. The control groups (1 and 5) received no treatment. Hyperbaric oxygen therapy was initiated immediately after surgery and continued for 4 days in groups 3 and 4. Groups 2 and 6 received recombinant human growth hormone, whereas groups 4 and 8 received GH and hyperbaric oxygen treatment. Relaparotomy was performed on postoperative day 4, and a perianastomotic colon segment 2 cm in length was excised for the detection of biochemical and mechanical parameters of anastomotic healing and histopathological evaluation. RESULTS: Combined treatment with hyperbaric oxygen and GH increased the mean bursting pressure values in all of the groups, and a statistically significant increase was noted in the ischemic groups compared to the controls (p<0.05). This improvement was more evident in the ischemic and normal groups treated with combined therapy. In addition, a histopathological evaluation of anastomotic neovascularization and collagen deposition showed significant differences among the groups. CONCLUSIONS: Combined treatment with recombinant human growth hormone and hyperbaric oxygen resulted in a favorable therapeutic effect on the healing of ischemic colonic anastomoses. .

Adrenomedulline improves ischemic left colonic anastomotic healing in an experimental rodent model

BACKGROUND: Leakage from colonic anastomosis is a major complication causing increased mortality and morbidity. Ischemia is a well-known cause of this event. This study was designed to investigate the effects of adrenomedullin on the healing of ischemic colon anastomosis in a rat model. METHODS: Standardized left colon resection 3 cm above the peritoneal reflection and colonic anastomosis were performed in 40 Wistar rats that were divided into four groups. To mimic ischemia, the mesocolon was ligated 2 cm from either side of the anastomosis in all of the groups. The control groups (1 and 2) received no further treatment. The experimental groups (3 and 4) received adrenomedullin treatment. Adrenomedullin therapy was started in the perioperative period in group 3 and 4 rats (the therapeutic groups). Group 1 and group 3 rats were sacrificed on postoperative day 3. Group 2 and group 4 rats were sacrificed on postoperative day 7. After careful relaparotomy, bursting pressure, hydroxyproline, malondialdehyde, interleukin 6, nitric oxide, vascular endothelial growth factor, and tumor necrosis factor alpha levels were measured. Histopathological characteristics of the anastomosis were analyzed. RESULTS: The group 3 animals had a significantly higher bursting pressure than group 1 (p<0.05). Hydroxyproline levels in group 1 were significantly lower than in group 3 (p<0.05). The mean bursting pressure was significantly different between group 2 and group 4 (p<0.05). Hydroxyproline levels in groups 3 and 4 were significantly increased by adrenomedullin therapy relative to the control groups (p<0.05). When all groups were compared, malondialdehyde and nitric oxide were significantly lower in the control groups (p<0.05). When vascular endothelial growth factor levels were compared, no statistically significant difference between groups was observed. Interleukin 6 and tumor necrosis factor alpha were significantly decreased by adrenomedullin therapy (p<0.05). The healing parameters and inflammatory changes (e.g., granulocytic cell infiltration, necrosis, and exudate) were significantly different among all groups (p<0.05). CONCLUSION: Adrenomedullin had positive effects on histopathologic anastomotic healing in this experimental model of ischemic colon anastomosis.

Letter to the Editor: A Case of Behcet's Disease with Massive Lower Gastrointestinal Bleeding / 대한소화기학회지

No abstract available.

Cecal Polypoid Arteriovenous Malformations Removed by Endoscopic Biopsy

Colonic arteriovenous malformation (AVM) is one of the causes of lower gastrointestinal bleeding. Unlike small vascular ectasia or angiodysplasia, colonic AVM tends to be solitary, large in size, and identified endoscopically as flat or elevated bright red lesion. Herein, we report a case of non-solitary and small cecal AVMs which were removed by endoscopic biopsy. A 66-yr-old woman was referred for routine gastrointestinal cancer screening. She was suffering from diabetes, hypertension, end-stage renal disease, and anemia of chronic disease. On colonoscopic finding, three semi-pedunculated polyps, less than 5 mm in size, were noticed near to the appendiceal orifice. Since the lesions revealed normal-looking epithelium with converging folds on the cecal base, lesions were diagnosed as inflammatory polyps on gross finding. Three biopsies were taken from each lesion. Bleeding from the biopsied site ceased spontaneously. Histopathologic evaluation demonstrated intramucosal hemorrhage and dilated submucosal vessels which were consistent with polypoid colonic AVMs.

Phlebosclerotic Colitis in a Cirrhotic Patient with Portal Hypertension: The First Case in Korea

Phlebosclerotic colitis is a rare form of ischemic colitis characterized by the thickening of the wall of the affected colon due to fibrous degeneration of submucosal layer of colon and fibrotic obstruction of the colono-mesenteric vein, resulting in the disturbance of venous return from the colon. The pathogenic mechanism of this entity remains unknown but chronic liver disease with portal hypertension is maybe thought to be one of the speculated mechanisms. Here we first report the case of surgically confirmed phlebosclerotic colitis, that was in the early stage but showed the aggressive nature, in a 61-yr-old cirrhotic patients with portal hypertension in Korea.

Consideraciones anatómicas sobre la irrigación de la flexura cólica derecha / Anatomic considerations about the irrigation of the right colic flexure

El estudio tuvo por objetivo describir la irrigación de la flexura cólica derecha, con la finalidad de proporcionar conocimientos anatómicos más amplios respecto del tema, y que éstos puedan ser utilizados para mejorar la práctica quirúrgica. Fueron utilizadas 40 piezas anatómicas de abdomen de cadáveres humanos, de ambos sexos y diferentes edades, fijados en formaldehido al 10 por ciento, pertenecientes al Departamento de Morfología de la Universidad Federal de Alagoas, Brasil. Se observó que la flexura cólica derecha estaba irrigada: en la mayoría de los casos (42,5 por ciento) por la arcada anastomótica, formada por la rama ascendente de la arteria cólica derecha con la rama derecha de la arteria cólica media; en el 27,5 por ciento de los casos por la anastomosis entre la rama derecha de la arteria cólica media y la rama ascendente de la arteria íleo cólica; en el 22,5 por ciento de los casos por las ramas ascendente y descendente de la arteria cólica derecha y en el 7,5 por ciento de los casos por la anastomosis entre las ramas derecha e izquierda de la arteria cólica media. Podemos concluir que la arteria cólica media fue el vaso con mayor presencia (77,5 por ciento) en la irrigación de la flexura cólica derecha. La anastomosis predominante en la flexura cólica derecha ocurrió entre la rama ascendente de la arteria cólica derecha y la rama derecha de la arteria cólica media.

This study has as objective present data about the irrigation of the right colic flexure, in order to proportionate an ample anatomic understanding about this subject, and that can be useful to perfect the surgical exercise. Was utilized 40 abdominal anatomic pieces of human corpses, of both sexes and variable ages, fixed in formaldehyde at 10 percent, belonging to Departament of Morphology of the Universidade Federal de Alagoas, Brazil. Was observed that the right colic flexure was presented in the majority of the cases (42.5 percent) irrigated by the anastomotic arcade composed by ascending branch of right colic artery with the right branch of the middle colic artery; following by the anastomosis between the right branch of middle colic artery and the ascending branch of ileocolic artery, in 27.5 percent of the cases. The ascendant and descendant branches of the right colic artery nourished the right colic flexure in the 22.5 percent of cases; at the present the anastomosis between the right and left branches of the middle colic artery irrigated the right colic flexure in 7.5 percent of the cases. We concluded that the middle colic artery was the most present vase (77.5 percent) in irrigation of the right colic flexure. The most prevalent anastomosis in the right colic flexure occurred between the ascending branch of right colic artery and the right branch of middle colic artery.

Comparative study of the hyperbaric hyperoxygenation in ischemic colonic loops in rats

PURPOSE: To analyze and to evaluate the effect of the hyperbaric hyperoxygenation in the mechanical resistance of ischemic colon of rats. METHODS: Eighty rats, distributed in four groups of 20 animals in each one, were used. In group 1 (G1), the control group, ischemia was not caused. Group 2 was submitted to the lesser degree of ischemia. Group 3 was submitted to the intermediate degree of ischemia. In group 4, a bigger degree of intestinal ischemia was provoked. Each group was divided in two sub-groups of ten animals each: with hyperbaric chamber (CC) and without hyperbaric chamber (SC). The animals of the four CC subgroups were placed in an experimental hyperbaric chamber in order to inhale oxygen at 100 percent, at two Absolute Atmospheres, for 120 minutes, for a four-day consecutive period. The animals of the four SC subgroups were kept in environment air during the five days of the experiment. All animals have been submitted to the mechanical study of the intestinal loop by the pressure test of the rupture by liquid distension. The euthanasia occurred in the fifth post-operative day. RESULTS: Considering the ischemia factor, the four groups were different among them (p=0.0001). There was no statistical difference between subgroups CC and SC (p=0.3461). CONCLUSION: The hyperbaric oxygen-therapy did not present improvement on the induced ischemia in rats upright colic loop.

OBJETIVO: Analisar e avaliar os efeitos da hiperoxigenação hiperbárica na resistência mecânica do cólon isquêmico de ratos. MÉTODOS: Foram utilizados 80 ratos distribuídos em quatro grupos de 20 animais. No grupo 1, grupo controle, não se provocou isquemia. O grupo 2 foi submetido ao grau menor de isquemia. O grupo 3 foi submetido ao grau intermediário de isquemia. No grupo 4, provocou-se grau maior de isquemia intestinal. Cada grupo foi dividido em dois subgrupos de dez animais cada: com câmara hiperbárica (CC) e sem câmara hiperbárica (SC). Os animais dos quatro subgrupos CC foram colocados em uma câmara hiperbárica experimental para inalarem oxigênio a 100 por cento, a duas atmosferas absolutas, durante 120 minutos, por quatro dias consecutivos. Os animais dos quatro subgrupos SC foram mantidos somente em ar ambiente. Todos animais foram submetidos ao estudo mecânico da alça intestinal pelo teste de pressão de ruptura pela distensão por líquido. A eutanásia ocorreu no quinto dia pós-operatório. RESULTADOS: Os quatro grupos são diferentes entre si considerando o fator isquemia (p= 0.0001). Não houve diferença estatística entre os subgrupos CC e SC (p= 0.3461). CONCLUSÃO: A oxigenoterapia hiperbárica não apresentou melhora sobre a isquemia induzida em alça cólica íntegra de ratos.

Isquemia intestinal / Mesenteric ischemia

La isquemia mesentérica es una insuficiencia circulatoria inadecuada para los requerimientos de la pared intestinal. Su presentación suele ser de extrema gravedad con historia de dolor abdominal crónico y/o infarto intestinal, con alta mortalidad y diagnóstico tardío. En el presente trabajo se realiza una revisión con los avances en el diagnóstico y manejo de esta condición, de acuerdo al compromiso vascular y los territorios afectados, con énfasis en su reconocimiento precoz y tratamiento agresivo, principalmente quirúrgico en los casos proximales al colon y médico en este último.

Right-sided colonic angiodysplasia in a young patient-a case report.

The histological diagnosis of angiodysplasia is one of the most difficult problems in G.I.T. pathology. These lesions are presumed to be degenerative in nature, commonly found in population over 60 years of age and rarely in young patients. So, diagnosis of angiodysplasia in this age group is even more difficult. We present a case of massive bleeding from colonic angiodysplasia in a 22-year-old female to increase awareness of this uncommon but potentially life threatening cause of lower intestinal bleeding in younger age group.

Efeito de aderências dirigidas em anastomoses cólicas isquêmicas em ratos / Effect of conducted adhesions on ischemic colic anastomoses in rats

OBJETIVO: Avaliar o efeito das aderências dirigidas sobre a resistência mecânica de anastomoses realizadas em cólon isquêmico através da aplicação dos testes Resistência à Pressão de Explosão e Resistência à Força de Tração. MÉTODOS: Quarenta ratos foram distribuídos igualmente em dois grupos. O Grupo 1 era constituído de vinte animais em que as anastomoses cólicas isquêmicas foram recobertas por uma película de polivinilcloreto (P.V.C.) para impedir a formação de aderências sobre as linhas de sutura e o Grupo 2 era constituído por 20 animais em que as anastomoses cólicas isquêmicas foram recobertas pela gordura epididimal, de forma a constituir uma aderência dirigida sobre a linha de sutura, sendo ainda recobertas por uma película de P.V.C. para impedir a formação de outras aderências. RESULTADOS: A média da Pressão de Ruptura à Distensão por Líquidos da anastomose foi de 10 mmHg no grupo sem aderência e de 55,2 mmHg no grupo com aderência (p < 0,05). A média da Força de Ruptura à Tração das anastomoses foi de 142,5 gf no grupo sem aderências e de 262 gf no grupo com aderência (p < 0,05). CONCLUSÃO: As aderências mostraram ser benéficas, elevando a resistência intrínseca das anastomoses tanto na Resistência à Distensão por Líquido quanto na Resistência à Força de Tração.

Estudo comparativo da hiperoxigenação hiperbárica em alças cólicas isquêmicas em ratos / Comparative study of the hyperbaric hyperoxygenation in ischemic colonic loops in rats

OBJETIVO: Analisar e avaliar os efeitos da hiperoxigenação hiperbárica na resistência mecânica do cólon isquêmico de ratos. MÉTODOS: Foram utilizados 80 ratos distribuídos em quatro grupos de 20 animais. No grupo 1, grupo controle, não se provocou isquemia. O grupo 2 foi submetido ao grau menor de isquemia. O grupo 3 foi submetido ao grau intermediário de isquemia. No grupo 4, provocou-se grau maior de isquemia intestinal. Cada grupo foi dividido em dois subgrupos de dez animais cada: com câmara hiperbárica (CC) e sem câmara hiperbárica (SC). Os animais dos quatro subgrupos CC foram colocados em uma câmara hiperbárica experimental para inalarem oxigênio a 100 por cento, a duas atmosferas absolutas, durante 120 minutos, por quatro dias consecutivos. Os animais dos quatro subgrupos SC foram mantidos somente em ar ambiente. Todos animais foram submetidos ao estudo mecânico da alça intestinal pelo teste de pressão de ruptura pela distensão por líquido. A eutanásia ocorreu no quinto dia pós-operatório. RESULTADOS: Os quatro grupos são diferentes entre si considerando o fator isquemia (p= 0,0001). Não houve diferença estatística entre os subgrupos CC e SC (p= 0,3461). CONCLUSÃO: A oxigenoterapia hiperbárica não apresentou melhora sobre a isquemia induzida em alça cólica íntegra de ratos.

Idiopathic colonic varices.

Idiopathic varices of the colon are rare, with only a few reports in literature. We report 30-year-old man who presented with melena and had hepatic flexure varices detected at colonoscopy. Investigations for portal hypertension were negative. No treatment was given.

Colonic mucosal changes in portal hypertension.

Forty one consecutive patients with portal hypertension (PHT) were evaluated by colonoscopy to study the prevalence, type, extent and predictors of haemorrhoids, colorectal varices, and portal hypertensive colopathy. Specific inquiry and regular follow-up assessed frequency of hematochezia. Twenty five patients with obscure gastrointestinal bleeding without PHT who underwent colonoscopy served as controls. Haemorrhoids were seen in nine of 41 (21.9%) patients with PHT and four of 25 (16%) controls (p = ns). Colorectal varices were seen in 13/41 (31.7%) patients with PHT and none of the controls (p = 0.005). Portal colopathy was present in 15/41 (36.6%) patients with PHT and none of the controls (p = 0.0005). None of the parameters (e.g. aetiology of PHT, Child's class, oesophageal variceal eradication by EST with or without EVL, history of variceal bleeding, grade of oesophageal varices, presence of portal hypertensive gastropathy or gastric varices) predicted the occurrence of colorectal varices and portal hypertensive colopathy. Detection of colorectal varices but not portal hypertensive colopathy was associated with occurrence of hematochezia.