The endoscopic spectrum of colonic mucosal injury following aortic aneurysm resection

Ischemic colitis is a serious complication of aortic aneurysm resection. A knowledge of the endoscopic appearance and the clinical course of various forms of colonic mucosal injury is important for the clinician who has to decide which patient should be carefully monitored after aneurysm resection. This article reports on 48 patients with colonic mucosal injury, subdivided into non-specific lesions and ischemic colitis. Details are given of the endoscopic picture and the clinical course. It is concluded that only the gangrenous form of ischemic colitis is of clinical significance, and is related to bowel perforation and late stricture formation.

Angiographic demonstration of bleeding in a unusually located Meckel's diverticulum simulating colonic bleeding

A case is reported in which bleeding from a Meckel's diverticulum was mistakenly localized to the hepatic flexure of the colon on superior mesenteric angiography. An unusually long and mobile mesentery, allowing the bleeding Meckel's diverticulum to be positioned high in the right upper quadrant, led to this misdiagnosis. The case illustrates several fundamental principles about the technique and interpretation of mesenteric angiograms.

[Acute mesenterial infarcts--results of surgical therapy]

Forty-five patients with mesenteric infarction documented by laparotomy or autopsy were reviewed. 35% of the patients had superior mesenteric artery occlusion by embolus, 27% by thrombosis, 11% had venous thrombosis, 9% nonocclusive mesenteric ischemia, and 18% were unclear. The mortality rate was 60% within half a year postoperatively. 22% had inoperable lesions, 46% underwent bowel resection, and 32% were managed by revascularization. In the group treated by bowel resection (n = 21) 30% died, in the group treated by revascularization 80% of the patients died.

Vascular anatomy of the equine small colon

The vasculature of 22 small colons from dead adult ponies was perfused with latex or barium sulphate solution. The vascular anatomy was studied by use of dissection and alkali digestion of the latex specimens and microangiography of the barium sulphate-perfused specimens. The small colon is supplied by the caudal mesenteric artery. The left colic artery arises from the caudal mesenteric artery, which then becomes the cranial rectal artery. Branches from the left colic and cranial rectal arteries form anastomosing arcades that become narrower distally along the length of the small colon. From these arcades arise terminal arteries, which enter the small colon wall and give rise to a subserosal, an intermuscular, and a large submucosal plexus, with frequent anastomoses between them. The venous drainage closely parallels the arterial supply, except near to its origin from the portal vein, when the left colic vein and caudal mesenteric vein are separate from the corresponding arteries.

Mortality from ischemic colitis

Thirty-nine hospital-based cases of ischemic colitis were reviewed. There were 18 males and 21 females. Average age was 68.7 years (range, 18 to 92 years). Associated diseases among 13 patients younger than 65 included renal failure in seven patients and hematologic, vasculitic, or collagen vascular diseases in four. In 26 patients 65 or older, congestive heart failure was seen in 13, vascular disease in eight, and previous aortic surgery in four. Nineteen patients were treated nonsurgically and 8 died (42 percent mortality). Twenty patients (51 percent) underwent surgery: 18 had resection with colostomy or ileostomy and two had resection with reanastomosis; one patient underwent laparotomy followed by second-look exploration without resection. Thirteen of the 20 surgical patients died (65 percent mortality). Both patients who underwent reanastomosis died of sepsis. The data show a close association between ischemic colitis and a number of serious systemic diseases including renal failure, arteriosclerotic heart and vascular disease, and hematologic, vasculitic, and connective-tissue disease. A predilection for the right colon and sigmoid colon and splenic flexure was seen. A formidable mortality rate (53 percent) was found among patients treated both surgically and nonsurgically.

The effects of slow infusion of a low dosage of endotoxin in healthy horses

The effects of slow intravenous (i.v.) infusion of a very low dosage of endotoxin (a cumulative dosage of 0.03 microgram/kg bodyweight [bwt] infused over 60 mins) were evaluated in six conscious healthy horses. Duodenal, right ventral colon, and caecal contractions were detected with strain gauge force transducers. Lateral caecal arterial blood flow was measured using transit time ultrasonic blood flow probes. Duodenal contractile activity was not significantly altered by infusion of endotoxin. In contrast, the contractile activity of the right ventral colon 90 and 270 mins after infusion of endotoxin was less than after infusion of saline solution (control). The contractile activity of the caecal body 30, 60, 90, 120 and 240 mins after infusion of endotoxin was significantly less than control. The contractile activity of the caecal apex 60, 90, 120, 240 and 270 mins after termination of endotoxin infusion was significantly less than control. Lateral caecal arterial blood flow was significantly less than control at the end of endotoxin infusion and at 30, 45, 60, 90, 105 and 120 mins afterwards. Average carotid arterial pressure was significantly greater than control at 210, 225, 240, 255 and 270 mins after endotoxin infusion. Infusion of endotoxin increased heart rate, respiratory rate and body temperature significantly. The decrease in caecal contractile activity occurred before the increase in body temperature. All horses became depressed and developed injected mucous membranes. Signs of abdominal pain (including stretching, pawing, kicking at abdomen) were seen in four of the six horses.

Evidence of free radical (FR) involvement in ischemic colitis

Early ischemic colitis was induced in rats to evaluate the roles of FRs and intraluminal content. After 30 minutes of ischemia, biopsies for histology, conjugated dienes (CD) and malonaldehyde (M), presumptive marker of lipid peroxidation, were obtained at 0, 30, and 60 minutes reperfusion. Histology was unchanged. CD and M were elevated in ischemic and saline controls, and rose progressively during reperfusion; CD and M were essentially the same as non-ischemic controls during reperfusion with intraluminal corticosteroid (c) and Alcide (A). These agents may be beneficial in early ischemic colitis.

Ischemic colitis following abdominal aortic reconstruction for ruptured aneurysm. A 10-year experience

Between January 1, 1978, and December 31, 1987, a total of 103 patients had operations for ruptured abdominal aortic aneurysms. The average age was 73 years (range, 53 to 91 years). Thirty-two patients died during surgery or in the immediate postoperative period. In 19 of the remaining 71 patients ischemic colitis developed, an incidence of 27 per cent. This report reviews the clinical findings and course of these patients. The average age of patients developing ischemic colitis was 72 years (range, 53 to 90 years), not significantly different from the group as a whole. There was no correlation between the type of vascular reconstruction and the development of ischemic colitis. Eleven patients died and eight survived, for a mortality rate of 58 per cent. The most common clinical finding was diarrhea early in the postoperative period, which was noted in 20 patients. Thirteen of these patients had ischemic colitis confirmed by flexible sigmoidoscopy. Eight (62%) of these 13 patients survived; three were managed nonoperatively and five had colectomy. Six patients presented between postoperative days 9 and 20 with signs of increasing sepsis but with no diarrhea or other significant clinical findings; ischemic colitis was confirmed by sigmoidoscopy in all six patients. All of these patients died of septic complications. Seven patients with early postoperative diarrhea had normal sigmoidoscopic findings. None developed septic complications and five survived; two died of cardiac events.(ABSTRACT TRUNCATED AT 250 WORDS)

Colonic varices. Report of a case

A 14-year-old girl who had colonic bleeding caused by colonic varices is described. Upper gastrointestinal endoscopy, radiography of the small and large bowel, and vascular studies of the superior and inferior mesenteric arteries and the portal vein were all reported to be normal. Submucosal varices, however, were identified colonoscopically in relation to the hepatic flexure and the sigmoid colon. Dilatation of subserosal right colonic vascular channels was identified at operation. Right hemicolectomy was performed and there has been no further bleeding. No obvious mesenteric arteriovenous communications were identified histologically.

Fatty acid composition of umbilical arteries and veins: possible implications for the fetal EFA-status

Fatty acid compositions were determined of phospholipids, isolated from umbilical arteries and veins, obtained from Dutch neonates after vaginal delivery, terminating normal pregnancy. The fatty acid profiles of the cord vessels were characterized by the absence of eicosapentaenoic (timnodonic) acid, a low (2-3%) content of linoleic acid and reasonable amounts of arachidonic acid (10-15%) and docosahexaenoic (cervonic) acid (3-5%). Significant amounts of Mead acid (1-4%) and its direct elongation product (0.5-2%) were also observed. In each cord, the efferent blood vessels contained significantly more Mead acid and other fatty acids of the oleic acid (n-9) family and less fatty acids of the linoleic (n-6) and linolenic (n-3) families than the afferent blood vessel. This indicates that the essential fatty acid (EFA) status of 'downstream' neonatal tissue may be marginal. No signs of EFA-deficiency were observed in endothelial and smooth muscle cells in culture, or in blood vessels from adults. In all cords 22:5(n-6) was significantly higher in the artery compared to the vein, whereas for all other (n-6) fatty acids this difference was negative. Since the synthesis of 22:5(n-6) is known to be stimulated when the required amount of cervonic acid, 22:6(n-3), is too low, our observations also suggest that the cervonic acid status of the neonates investigated was not optimal. Further studies are in progress to relate these findings to maternal EFA status and complications of pregnancy.

[Angiodysplasia of the colon]

Ascending colon angiodysplasia is a cause of colorrhagia, particularly if the patients are more than 55 years old. Therapy is primarily surgical and it consists generally in right hemicolectomy. Two cases personally observed are reported and a survey of the literature is made.

Ultrastructural localization of lysozyme in human colon eosinophils using the protein A-gold technique: effects of processing on probe distribution

The distribution of lysozyme (muramidase) within eosinophil leukocytes situated in the lamina propria of human colon was studied by immunoelectron microscopy using a range of standard techniques. Tissue processed in a variety of glutaraldehyde- or paraformaldehyde-based fixatives was partially dehydrated and embedded in the acrylic resin LR White. Tissue thus treated showed lysozyme in pale cytoplasmic granules and the matrix of specific granules, but not in their crystalloids. Trypsinization of sections had little effect on this result, and tissues fixed in glutaraldehyde and embedded in Araldite showed a low level of reactivity with a similar distribution. After etching LR or Araldite sections with sodium metaperiodate, the pale granules and specific granule matrices became negative for lysozyme and the crystalloids became positive. Because crystalloids also were labeled with normal rabbit immunoglobulin after etching, this apparent redistribution of label could be due to nonspecific binding rather than exposure of masked epitope.

[Vascularization of the colonic flexures. An anatomo-radiologic study (VI)]

The Authors briefly report the data obtained from a study of the blood supply to colonic flexures. In spite of many Authors' different opinions, colonic flexures are adequately supplied by the same colonic arteries through secondary vessels as well as by the blood flow of other vascular regions.

[Regional ischemia/necrosis after surgery of lumbal aortic aneurysm]

Following operation for aneurysm of the abdominal aorta two patients developed buttock necrosis. One procedure was elective and one was an emergency procedure. Patient 1 in addition developed paralysis of the leg on the same side as the buttock necrosis, while patient 2 in addition developed colon ischemia. Both patients died from these complications. Buttock necrosis and paralysis are rare complications after operation for abdominal aortic aneurysm. Regional ischemia of the left colon is a more common complication. The case report illustrates the importance of the pelvic-femoral collaterals. In addition we emphasize the importance of maintaining or restoring hypogastric circulation in order to prevent these complications.

[Our experience with ischemic colitis]

Personal experience in seven cases of ischaemic colitis that required surgery is reported. The aetiological, pathological and clinical features of the disease are then considered.

Colonic complications of severe acute pancreatitis

Colonic complications are rare in acute pancreatitis. Over the last 9 years at St. Mary's Hospital, London, UK, we have managed severe acute pancreatitis by intensive supportive therapy followed by sub-total pancreatic resection and/or debridement in those who fail to improve. Of the 22 patients who have undergone this form of surgery, nine were found to have colonic involvement in the form of either necrosis or perforation. In addition, one patient presenting at West Middlesex University Hospital, Isleworth, UK, had severe acute pancreatitis and almost total colonic necrosis as an unexpected finding at emergency laparotomy. These ten patients comprised seven men and three women of median age 59 years and with a median of four Ranson criteria. In seven patients, colonic involvement was discovered at the time of pancreatic surgery or laparotomy for pancreatitis and in the remainder it presented between 1 and 3 weeks later as either a faecal fistula (n = 2) or persistent abdominal sepsis (n = 1). The ascending colon was involved in one patient, the splenic flexure and descending colon in one, the transverse colon in three, the splenic flexure alone in four, and one patient had almost total colonic involvement. All patients underwent resection of the involved colon and exteriorization with either a proximal colostomy (n = 7) or ileostomy (n = 3) and a distal mucous fistula. Pathological examination of the resected colons revealed a spectrum of changes from pericolitis through to ischaemic necrosis suggesting at least two possible mechanisms. Six patients died from overwhelming sepsis between 1 day and 4 weeks (median 11 days) after colonic resection. Severe acute pancreatitis must be recognized as a cause of colonic ischaemia and necrosis; this complication is associated with a very poor prognosis despite surgical intervention.

Idiopathic entero-colic lymphocytic phlebitis. A cause of ischemic intestinal necrosis

Histological examination of the surgical specimens of three patients presenting with intestinal ischemic necrosis disclosed extensive lesions of lymphocytic phlebitis associated with thrombosis of different ages. Arterioles and arteries were not affected. The lymphocytic infiltrate was composed of a mixture of T- and B-lymphocytes. None of the patients showed clinical or laboratory evidence of systemic vasculitis. Follow-up ranged between 4 months and 5 years. There has been no recurrence necessitating reoperation. The etiology of this clinicopathological entity has not been elucidated.

Colonic angiodysplasia. Follow-up of patients after endoscopic treatment for bleeding lesions

Endoscopic electrocoagulation or photocoagulation is now the method of choice for treating colonic angiodysplasia. Follow-up of such patients has not been extensive. The authors report 26 patients with typical and symptomatic lesions who have been treated endoscopically. Follow-up (mean duration, 29.3 months) revealed that 21 patients remained symptom-free after a single procedure. Two patients needed a second procedure before being considered cured. In two others, the need for transfusions was lessened considerably after treatment. The last patient died of terminal cardiac failure. No complications occurred during treatment. Endoscopic treatment is a safe and efficient method for treating bleeding colonic angiodysplasia.