Bacterial translocation and mortality on rat model of intestinal ischemia and obstruction.

PURPOSE:: To develop an experimental model of intestinal ischemia and obstruction followed by surgical resection of the damaged segment and reestablishment of intestinal transit, looking at bacterial translocation and survival. METHODS:: After anesthesia, Wistar rats was subject to laparotomy, intestinal ischemia and obstruction through an ileal ligature 1.5cm of ileum cecal valve; and the mesenteric vessels that irrigate upstream of the obstruction site to approximately 7 to 10 cm were ligated. Abdominal wall was closed. Three, six or twenty-four hours after, rats were subject to enterectomy followed by an end to end anastomosis. After 24h, mesenteric lymph nodes, liver, spleen and lung tissues were surgically removed. It was studied survival rate and bacterial translocation. GraphPadPrism statistical program was used. RESULTS:: Animals with intestinal ischemia and obstruction for 3 hours survived 24 hours after enterectomy; 6hx24h: survival was 70% at 24 hours; 24hx24h: survival was 70% and 40%, before and after enterectomy, respectively. Culture of tissues showed positivity on the 6hx24h and negativity on the 3hx24h. CONCLUSION:: The model that best approached the clinic was the one of 6x24h of ischemia and intestinal obstruction, in which it was observed bacterial translocation and low mortality rate.

Bacterial translocation and mortality on rat model of intestinal ischemia and obstruction

Abstract Purpose: To develop an experimental model of intestinal ischemia and obstruction followed by surgical resection of the damaged segment and reestablishment of intestinal transit, looking at bacterial translocation and survival. Methods: After anesthesia, Wistar rats was subject to laparotomy, intestinal ischemia and obstruction through an ileal ligature 1.5cm of ileum cecal valve; and the mesenteric vessels that irrigate upstream of the obstruction site to approximately 7 to 10 cm were ligated. Abdominal wall was closed. Three, six or twenty-four hours after, rats were subject to enterectomy followed by an end to end anastomosis. After 24h, mesenteric lymph nodes, liver, spleen and lung tissues were surgically removed. It was studied survival rate and bacterial translocation. GraphPadPrism statistical program was used. Results: Animals with intestinal ischemia and obstruction for 3 hours survived 24 hours after enterectomy; 6hx24h: survival was 70% at 24 hours; 24hx24h: survival was 70% and 40%, before and after enterectomy, respectively. Culture of tissues showed positivity on the 6hx24h and negativity on the 3hx24h. Conclusion: The model that best approached the clinic was the one of 6x24h of ischemia and intestinal obstruction, in which it was observed bacterial translocation and low mortality rate.

Severe Mesenteric Hemorrhagic Infarction by Superior Mesenteric Arterial Occlusion in a Patient with Buerger's Disease / 대한소화기학회지

No abstract available.

Consideration of the blood supply of the ileocecal segment in valve preserving right hemicolectomy.

The ileocecal valve (ICV) is known to control the flow of chyme and to prevent bacterial colonization of the small intestine. Preservation of this segment during right hemicolectomy is likely to prevent loss of its function. This study aimed at evaluating the arterial supply of the ICV to help preserve the valve during right hemicolectomy. Fifty-four fresh human cadavers (37 male, 17 female; median age: 54 years, range: 18-90 years) were studied after relatives gave written, informed consent. At postmortem, 20 cm of terminal ileum with the ileocecal segment and up to 20 cm of ascending colon were removed en bloc with its mesentery and blood supply. The ileocolic artery was cannulated and injected with 10 ml of water-soluble red dye under pressure. The arterial supply was dissected to demonstrate a pattern. In all, the ICV was supplied by the ileocolic artery, a branch of the superior mesenteric, which divided into an anterior and a posterior cecal artery. A marginal branch of the right colic was noted to contribute to ICV blood supply in only two (4%). Furthermore, study of the anastomosis at the ICV showed that the anterior cecal artery was present in all (100%), posterior cecal in 48 (89%), and recurrent ileal artery in 53 (98%). A rich anastomosis between vessels at the ICV; small "windows," short tributaries, were seen in 38 (70%), whereas a poor anastomotic network at the ICV; large "windows," long tributaries, between these vessels were seen in 12 (22%). In four (8%), we were unable to clearly determine between rich and poor anastomotic networks. Other variants included, absent posterior cecal artery in six (11%) and absent recurrent ileal artery in one (2%). The ICV has a predictable blood supply in the majority of patients. Preservation of the anterior cecal artery would ensure a vascularized ICV in right hemicolectomy.

[Ileoascendoanastomosis]. / Ileoastsendoanastomoz.

A complex anatomical investigation of the extra- and intra-organic vessels of the ascending colon has shown that the formation of ileoascendoanastomosis is possible and expedient without a preliminary intraoperative assessment of the vascular bed. The indications to such operation are developed. The extirpation of the blind gut and resection of the ascending colon with applying the anastomosis in question was performed on 6 patients with carcinoma of the blind gut and ascending colon. The results of operations were good.

Superior mesenteric artery Doppler waveform changes in response to inflammation of the ileocecal region.

In the present study, we determined how Doppler waveforms of the superior mesenteric artery (SMA) are affected by inflammatory processes in the ileocecal region. Twenty-two patients (aged 20-69 years) with ileocecal region inflammation (ICRI) were examined with duplex Doppler Ultrasonography to establish whether any significant changes were present in the mean blood flow parameters of peak systolic velocity (PSV), end-diastolic velocity (EDV), resistive index, pulsatility index, blood flow volume, and diameter of the SMA. The findings were compared with those of 22 volunteer controls. Mean blood flow volume in the SMA in patients with ICRI (1.128 +/- 0. 43 L/min) was significantly greater (p < 0.001) than that in the control group (0.643 +/- 0.19 L/min). The mean PSV (1.87 +/- 0.44 m/s) and the mean EDV (0.31 +/- 0.18 m/s) were also significantly (p < 0.01) higher than those of the means in healthy subjects (mean PSV = 1.44 +/- 0.26 m/s and mean EDV = 0.20 +/- 0.05 m/s). ICRI, regardless of cause, increases both the flow velocities in the SMA and the flow volume to the SMA territory.

Value of CT in localizing site of gastrointestinal hemorrhage following negative angiography.

This case report of severe gastrointestinal (GI) bleeding demonstrates the utility of computed tomography (CT) in localizing such hemorrhages when all other diagnostic modalities have been exhausted. All previous studies in this case were nondiagnostic. However, abdominal CT performed without the benefit of oral contrast but immediately following negative angiography was useful in directing the surgeon to the region of hemorrhage by documenting the presence of focally dense intraluminal contrast within the small bowel loops.

[Vascular anatomic principles of surgery of the terminal ileum]. / Gefässanatomische Grundlagen der Chirurgie des terminalen Ileums.

The terminal ileum has a reputation for poor vascularisation. In nontumoral lesions a maximum preservation of the terminal ileum and the ileocaecal valve for functional reasons should be aimed at. Therefore we carried out a study on 200 cadavers by preparation of the superior mesenteric artery and the ileocolic artery and their branches. We used the classification of the arrangements of the arteries of the terminal ileum of Chevrel und Guéraud. We found a lower origin of the anastomosis between the superior mesenteric artery and the ileocolic artery in 56%, an upper origin in 44%. A recurrent ileal artery was present in 84%. Surgical applications can be drawn from this study.

Mesenteric varices: an entity with specific clinical, angiographic features.

Eight Japanese patients with mesenteric varices were diagnosed by angiography. All patients suffered from portal hypertension and had a history of previous abdominal surgery or peritonitis. The mesenteric varices of these patients were thought to be related to adhesion. Of the eight patients, five showed hepatic encephalopathy. None of the patients had a history of massive lower-gastrointestinal bleeding. All mesenteric varices were opacified in the portal phase of superior mesenteric arteriograms. To study the superior mesenteric artery, 50-60 ml of 76% Urografin was injected after infusion of prostaglandin E1 or F2 alpha. Regarding patients treated in the early part of the study, a vasodilator was not used and the contrast dosage was modest. In all eight patients, the mesenteric varices communicated with the systemic venous circulation through the gonadal veins. In seven cases, the mesenteric varices on the right side of the mesenteries drained into the right gonadal veins which flowed into the inferior vena cava (IVC). In the remaining case, the mesenteric varix on the left side drained into the left gonadal vein which flowed into the left renal vein. In three patients with right-sided varices, venous blood sampled from the right gonadal vein and from the distal and proximal IVC showed a high concentration of ammonia in the right gonadal vein and step-ups between distal and proximal IVC.

[Bioconstruction of the human ileocaecal valve (author's transl)]. / Die Biokonstruktion der Valva ileocaecalis des Menschen.

The lips of the ileocaecal valve are permanent folds parallel to the long axis of the small intestine, which are formed by invagination of all layers of the terminal ileum into the caecum. In the basal two-thirds they contain processes of all muscular layers of ileum and caecum, which form a system of muscle bundles that is connected with the tunica muscularis mucosae. The luminal part of the lips contains a venous plexus embedded in the loose plexus of the tunica mucosa. Arteriovenous anastomoses facilitate the rapid filling of these venous plexus. The ileocaecal valve in humans acts as a combined angiomuscular-angioplical lock-system that under normal conditions prohibits a caeco-ideal reflux.

Sympathetic nervous control of cat ileocecal sphincter.

A perfusion method was designed in order to investigate that effects of stimulation of the splanchnic and lumbar colonic nerves on the ileocecal sphincter (ICS) of the cat. Splanchnic and lumbar colonic nerve stimulation at physiological frequencies, i.e., below 10-12 impulses/s, elicited a contraction of the sphincter concomitant with an inhibition of the motility of the adjacent parts of the small and large intestines. It is concluded that the splanchinc and lumbar colonic nerves contract the ICS by a direct effect on the sphincter and not via a contraction of the intestine surrounding the sphincter. Guanethidine and phenoxybenzamine but not propranolol blocked the contraction of the ICS. It is suggested that the splanchnic and lumbar colonic nerves control the sphincter via an alpha-adrenergic mechanism. Inhibitory fibers within the splanchnic or lumbar colonic nerves to the ICS were not found. The excitatory in the ICS elicited by adrenaline, nor-adrenaline, or phyenylephrine infusion was completely blocked by phenoxybenzamine. Propranolol did not block the effect on ICS of these drugs. On the contrary, an augmented response could be shown, indicating unmasking of an excitatory alpha-receptor response by blockade of inhibitory beta-receptors. Further support for these inhibitory beta-receptors was provided by the finding that isoprenaline had a relaxing effect on the sphincteric muscle, an effect that was blocked by propranolol. In order to block the inhibitory effect on the small and large intestine elicited by splanchnic and lumbar colonic nerve stimulation, both phenoxybenzamine and propranolol had to be administered.