Colorectal obstruction

Insertion of self-expanding metallic stents is now a well-established method to treat obstructions of the biliary tract (Rossi et al. 1994) and the oesophagus (Song et al. 1994 Adam et al. 1997). Recently their use has been extended to gastroduodenal outlet obstruction and treatment of acute ileus in colorectal obstruction. Patients with malignant gastroduodenal as well as colorectal obstruction are often elderly,... 

In this chapter we describe the indications, results and problems with stenting of gastroduodenal and colorectal obstruction. 

Adler DG, Baron TH (2000b) Stents and lasers for colonoscopic lesions. Curr Gastroenterol Rep 2 399-405 Ahmad T, Mee AS (2000) Expandable metal stents in malignant colorectal obstruction. BMJ 321 584 585 Baron TH (2001) Expandable metal stents for the treatment of cancerous obstruction of the gastrointestinal tract. N Engl J Med 344 1681-1686... 

De Gregorio MA, Mainar A, Tobio R (1998) Acute colorectal obstructions stent placement for palliative treatment - results of a multicenter study. Radiology 209 117-120 De Lange EE, Shaffer HA (1991) Rectal strictures, treatment with fluoroscopically guided balloon dilatation. Radiology 178 475-479... 

Mainar A, Tejero E, Maynar M, Ferral H, Castaneda-Zuniga WR (1996) Colorectal obstruction treatment with metallic stents. Radiology 198 761-764... 

Mainar A, De Gregorio MA, Tejero E, Tobio R, Alfonso E, Pinto I, Herrera M, Fernandez JA (1999) Acute colorectal obstruction treatment with self-expandable metallic stents before scheduled surgery - results of a multicenter study. Radiology 210 65-69... 

Mauro AM, Koehler RE, Baron TH (2000) Advances in gastrointestinal intervention the treatment of gastroduodenal and colorectal obstructions with metallic stents. Radiology 215 659-669... 

Camunez F, Echenagusia A, Simo G, Turegano F, Vazquez J, Barreiro-Meiro I (2000) Malignant colorectal obstruction treated by means of self-expanding metallic stents effectiveness before surgery and in palliation. Radiology 216(2) 492-497... 

Colorectal (emergency surgery or obstruction) Enteric gram-negative rods, anaerobes Cefoxitin, cefotetan, or cefazolin + metronidazole... 

Breast cancer Colorectal cancer Renal cell cancer Endometrial cancer Asthma Chronic obstructive pulmonary disease (COPD) Chronic bronchitis Sleep apnea Impaired wound healing Impaired immune response Renal failure Infertility Incontinence Renal failure... 

Overall, surgery for colorectal cancer is associated with a morbidity and mortality rate of 8% to 15% and 1% to 2%, respectively, depending on the type and extent of procedure. - Common complications associated with colorectal surgery include infection, anastomotic leakage, obstruction, adhesion formation, and malabsorption syndromes. 

Adverse effects associated with XRT in colorectal cancer can be acute or chronic. Acute effects primarily include hematologic depression, dysuria, diarrhea, abdominal cramping, and proctitis. Chronic symptoms that sometimes persist for months following discontinuation of XRT may involve persistent diarrhea, proctitis or enteritis, small bowel obstruction, perineal tenderness, and impaired wound healing. 

Corticosteroids are used in clinical practice to relieve pressure symptoms caused by many tumor types, notably intracerebral tumors but also those causing airway or central venous obstruction. Their mode of action has been studied in animals (57) and humans (58), and is thought to involve first constriction of tumor vascular volume and then a reduction in water content. Reduced interstitial pressure should increase perfusion and extravascular diffusion rates, and high doses of steroids have been shown to increase blood flow in human colonic tumors transplanted into mice. Uptake of antibody into tumors has been assessed before and after administration of high-dose dexamethasone to decrease tumor interstitial pressure and thus increase antigen accessibility. Three patients with recurrent colorectal carcinoma had two antibody scans each, 72 h apart, and the injected dose was the same for all scans (20 mg). Dexamethasone was started 24 h before the second dose of antibody, with an initial iv dose of 10 mg followed by 4 mg four times daily orally for 48 h. 

However bowel preparation should be tailored to the indication, with full or reduced cathartic preparation associated to tagging of fluids or stool. Adequate colonic distension (pneumocolon) is cru-dal for identification of colorectal polyps and differentiation between obstructive cancers and a collapsed segment. Distension is achieved by rectal air or carbon-dioxide insufflation, and standard scout view in lateral and anterior-posterior projections are acquired to verify the distension of the entire colon. The intravenous administration of a muscle rdaxant, to reduce large bowel movement and... 

CTC in symptomatic patients is to be considered when colonoscopy can not be completed or carried out this may occur due to mechanical hindrance such as pelvic adhesions, in cases of high risk of perforation as in complicated diverticular disease, when there is an obstruction due to cancer or extracolonic diseases, when the cecum cannot be reached in extreme dolicocolon conditions, or in patients with poor tolerance to colonoscopy in whom heavy sedation may be dangerous (elderly patients or patients with severe co-morbidity). Such indications are similar to those of double contrast barium enema (DCBE) however, CTC has been shown to be both more accurate and better tolerated than DCBE, and should be used preferentially whenever available (Rocket et al. 2005 Taylor et al. 2005 Taylor et al. 2006). Furthermore, in cases of obstructing colonic cancer, CTC is a valuable tool, as it can be conveniently performed at the time of a contrast-enhanced abdominal CT scan for staging purposes to detect synchronous colorectal carcinomas, metas-... 

Acute obstruction of the colon and rectum is caused by a number of benign and malignant diseases but by far the most frequent aetiology is colorectal carcinoma (Parker et al. 1997 Deans et al. 1994). Other maUg-nant causes include infiltration from adjacent mahg-nant tumour and metastatic involvement. Benign conditions such as diverticuhtis or other inflammatory bowel diseases (Crohn s disease, tuberculosis) and anastomotic or post-irradiation strictures are less frequent (Cascales-Sanchez et al. 1997 Rodier et al. 1987 De Lange and Shaffer 1991). 

According to Binkert et al. (1998) cost savings of up to 29% can be achieved in preoperative stent placement for colonic carcinoma. However, no completed randomised prospective study has compared preoperative stenting with standard surgery in patients with potentially resectable primary colorectal cancer and obstruction. Currently such a study is under way in the United States (Baron 2001). 

Di Sario JA, Fennerty MB, Tietze CC (1994) Endoscopic balloon dilatation for ulcer-induced gastric outlet obstruction. Am J Gastroenterol 89 868-871 Dohmoto M (1991) New method-endoscopic implantation of rectal stent in palliative treatment of malignant stenosis. Endoscopia Digestiva 3 1507-1512 Eckhauser ML (1992) Laser therapy of colorectal carcinoma. 

Saida Y, Sumiyama Y, Nagao J, Takase M (1996) Stent endoprosthesis for obstructing colorectal cancers. Dis Colon Rectum 39 552 555... 

Tejero E, Mainar A, Fernandez L, Tolio R, De Gregorio MA (1994) A new procedure for the treatment of colorectal neoplastic obstructions. Dis Colon Rectum 37 1158-1159 Tejero E, Fernandez-Lobato R, Mainar A, Montes C, Pinto I, Fernandez L, Jorge E, Lozano R (1997) Initial results of a new procedure for treatment of malignant obstruction of the left colon. Dis Colon Rectiun 40 432-436... 

The indications for CTC closely follow the indications for conventional optical colonoscopy with few exceptions. These indications include screening asymptomatic high- and average-risk patient populations, pre-operative assessment of the colon proximal to an obstructing mass, evaluation of patients with change in bowel habits, surveillance of patients post colorectal cancer surgery, and incomplete or failed colonoscopy. Patients with bleeding diathesis, contraindications to sedation, and frail and elderly patients may also be better suited for CTC than conventional colonoscopy. 

Contraindication to sedation Obstructing colon mass Post-operative colorectal cancer surveillance High risk patients Scanner weight limitations Pregnancy Hip joint replacement Incompetent ileocecal valve Claustrophobia ... 

Double contrast barium enema remains in the algorithm for work-up of colorectal cancer in evaluation of the proximal bowel in cases of an obstructing mass. This examination is not preferred, as the proximal colon often does not drain all of the barium by the time of surgery. Patients are also at increased risk for post-operative morbidity if a reactive peritonitis develops secondary to barium contamination intr a- operatively. 

Morrin MM, Farrell RJ, Raptopoulos V, McGee JB, Bleday R, Kruskal JB (2000a) Role of virtual computed tomographic colonography in patients with colorectal cancers and obstructing colorectal lesions. Dis Colon Rectum 43(3) 303-311... 

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