Current management of patients with lower gastrointestinal bleeding

Role of colonoscopy in the diagnosis and treatment of pediatric lower gastrointestinal disorders

The safety and effectiveness of colonoscopy in the investigation of lower gastrointestinal tract pathology in children has been established for more than 2 decades in Korea. Skill and experience have since advanced to the point that both diagnostic and therapeutic colonoscopy are now routinely performed by most pediatric gastroenterologists. Pediatric colonoscopy differs significantly from its adult parallels in nearly every aspect including patient and parent management and preparation, selection criteria for sedation and general anesthetic, bowel preparation, expected diagnoses, instrument selection, imperative for terminal ileal intubation, and requirement for biopsies from macroscopically normal mucosa. Investigation of inflammatory bowel disease, whether for diagnosis or follow-up evaluation, and suspected colonic polyps are the most common indication for pediatric colonoscopy. The child who presents with signs and symptoms of lower gastrointestinal disorder should undergo colonoscopy with biopsy to make the diagnosis, as well as to help determine the appropriate therapy. This review introduces practical information on pediatric colonoscopy, the author's experiences, and the role of colonoscopic examination in the diagnosis and treatment of pediatric lower gastrointestinal disorders.

Microcatheter embolization of lower gastrointestinal hemorrhage: an old idea whose time has come

Early attempts of using embolization for lower gastrointestinal hemorrhage were fraught with complications, most notably ischemic colitis or bowel infarction. Embolotherapy was eventually abandoned in favor of catheter-directed vasoconstriction (i.e., vasopressin infusion). This latter therapy is time and labor intensive. With the advent of microcatheter technology, superselective embolization emerged and is rapidly becoming the endovascular therapy of choice for patients with severe lower gastrointestinal hemorrhage refractory to medical management. Numerous studies on the subject have consistently reported high clinical success with low ischemic complications. This article will review the current status of co-axial microcatheter embolization with an emphasis on the technical aspects of the procedure.

Lower gastrointestinal bleeding

BACKGROUND

Lower gastrointestinal bleeding can be a confusing clinical conundrum, the satisfactory evaluation and management of which requires a disciplined and orderly approach. Diagnosis and management has evolved with the development of new technology such as selective mesenteric angiography and colonoscopy.

PURPOSE

This study was undertaken to review the available data in the literature and to determine the current optimum method of evaluation and management of lower gastrointestinal hemorrhage most likely to result in a successful outcome.

METHODS

Data available on the topic of lower gastrointestinal bleeding in the English literature were obtained via MEDLINE search and were reviewed and analyzed.

RESULTS

The colonic origin of lower gastrointestinal hemorrhage in order of decreasing incidence is diverticulosis, inflammatory bowel disease, including ischemic and infectious colitis, colonic neoplasia, benign anorectal disease, and arteriovenous malformations. Approximately 10 to 15 percent of all cases of rectal bleeding are attributable to a cause that is proximal to the ligament of Treitz. Small intestinal sources such as arteriovenous malformations, diverticula, and neoplasia account for between 3 and 5 percent of all cases. Colonoscopy successfully identified an origin in severe hematochezia in 74 to 82 percent of cases. Mesenteric angiography has a sensitivity of 42 to 86 percent. The best method of management depends on whether hemorrhage persists, the severity of continued hemorrhage, the cumulative transfusion requirement, and the specific origin of bleeding.

CONCLUSION

Lower gastrointestinal hemorrhage is a complex clinical problem that requires disciplined and sophisticated evaluation for successful management. Diverticulosis is the most common cause. Colonoscopy is the diagnostic procedure of choice both for its accuracy in localization and its therapeutic capability. Selective mesenteric angiography should be reserved for those patients in whom colonoscopy is not practical. Precise identification of the bleeding source is crucial for a successful outcome. Specific directed therapy, such as segmental colonic resection for bleeding diverticulosis, is associated with the highest success rate and the lowest morbidity. A complete review of lower gastrointestinal bleeding is contained herein.

Effectiveness of current technology in the diagnosis and management of lower gastrointestinal hemorrhage

Lower gastrointestinal hemorrhage is a common clinical problem for which multiple diagnostic tests and therapeutic interventions have been developed but no optimal approach has been established. We reviewed 107 consecutive patients admitted to the Massachusetts General Hospital for management of acute lower gastrointestinal hemorrhage to determine the effectiveness of diagnostic and management technologies, with particular attention to urgent colonoscopy. Colonoscopy yielded a diagnosis in 90% of patients, provided the opportunity for successful therapy in 9 of 13 patients (69%), and shortened hospital stay. Angiography performed after a scan positive for bleeding was often diagnostic, and angiography provided the means for successful therapy in 5 of 10 patients (50%). Barium enema and sigmoidoscopy had lower clinical yields. Although roles exist for other technologies, colonoscopy is the most convenient and effective first test in the evaluation of patients with significant lower gastrointestinal hemorrhage. Diagnostic yield, therapeutic opportunity, and cost effectiveness are maximized in early studies.

Acute lower gastrointestinal bleeding

Lower gastrointestinal bleeding ranges from occult blood loss to massive hemorrhage and shock. There are many causes but diverticulitis and angiodysplasia remain the most common sources of major hemorrhage. This article emphasizes the cause and evaluation of moderate to severe acute lower gastrointestinal bleeding.

Lower gastrointestinal bleeding. A systematic approach to classification and management

Early classification of lower gastrointestinal bleeding as occult, minor overt, or major overt allows a practical approach to evaluation and management. Localization of the bleeding site is the next step. In occult and minor overt bleeding, the cause can usually be determined from results of conventional diagnostic tests; however, angiography and even intraoperative endoscopy may be necessary in some particularly difficult cases. In contrast, major overt bleeding may only allow time for angiographic localization before surgery. Using this approach, the primary care physician can successfully manage most patients with lower gastrointestinal bleeding.