Clinical Management of Obscure- Overt Gastrointestinal Bleeding. Presented by Dr. 張瀚文

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1 Clinical Management of Obscure- Overt Gastrointestinal Bleeding Presented by Dr. 張瀚文

2 Definition Obscure: : hard to understand; not clear. Overt: : public; not secret. Occult: : hidden from the knowledge or understanding of ordinary people.

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4 Obscure GI bleeding A negative diagnostic evaluation consisted of a negative upper endoscopy and colonoscopy, perhaps with the addition of small bowel radiographic evaluation. 5% of patients with overt GI hemorrhage will have negative upper endoscopy and colonoscopy.

5 Obscure Small-Bowel Bleeding Vascular ectasia : associated with advanced age, chronic renal failure, valvular heart disease, von- Willebrand s disease, CREST syndrome. Small bowel tumors: GI stromal tumors, adenocarcinoma,, lymphoma, carcinoid,, Kaposi s sarcoma, and metastatic tumors. Ulcerations or erosions due to Crohn s disease or NSAID use. AV fistula. Meckel s diverticulum. Polyps Varices.

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7 Patient Observation Iron-replacement replacement therapy. Correction of existing coagulopathies or platelet abnormalities. Intermittent transfusion. Blood loss is small. The risk of further interventional diagnostic modalities.

8 Repeat Upper Endoscopy Repeat upper endoscopy or push enteroscopy can find a source of hemorrhage within reach of a standard gastroscope in 28%-75% obscure GI bleeding. Lesions commonly missed: gastric or duodenal vascular ectasias,, Cameron s s erosions or ulcers within a hiatal hernia sac, peptic ulcers, malignancy, Dieulafoy s lesions, isolated gastric varices,, and gastric antral vascular ectasias.

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12 Push Enteroscopy Push enteroscopy may be performed directly instead of repeating upper endoscopy. Permit evaluation to cm beyond the ligament of Treitz. Diagnostic yield is reported to increase with a greater depth of scope insertion. Preferred over SBFT: better accuracy, ability to obtain tissue, perform polypectomy or hemostasis,, and mark the bleeding location. Does not allow visualization of the entire small bowel. Complications: perforation, mucosal lacerations.

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14 Repeat Colonoscopy Colonic lesions missed at initial colonoscopy have been reported in up to 3% of patients with obscure GI bleeding. Missed lesions: vascular ectasias, neoplasms,, and diverticular disease. Cecal intubation?? Bowel preparation? terminal ileum evaluation?

15 Small-Bowel Contrast Radiography Poor sensitivity in identifying definite lesions on obscure bleeding(0%-6%). Inability to diagnose flat mucosal and subepithelial lesions. Small-bowel enteroclysis: diagnositc yield still low (10%-25%), more uncomfortable, more radiation exposure.

16 Nuclear Medicine Tagged Red Blood Cell Scan Technetium-99m 99m-labeled RBC scan: long-life life of technetium allows for delayed scans to be performed for up to 24 hours. Overall rate of positive tagged RBC scans is about 45%(26%-78%). Early scans may be helpful in gross localization of bleeding when the rate of blood loss exceeds ml/min. Delayed scans :pooling of blood in the bowel. Intermittent nature of GI bleeding may result in false- negative scans.

17 Angiography It is more likely to document the specific site of bleeding than tagged RBC scan, yet the bleeding rate must be >0.5 ml/min. Can identify lesions that are not actively bleeding because of demonstration of typical vascular features seen in vascular ectasias and tumors. Administer embolization therapy. Provocative angiography using anticoagulants, vasodilators, or thrombolytic agents.

18 Pennazio et al Gastroenterology 2004

19 Pennazio et al Gastroenterology 2004

20 Pennazio et al Gastroenterology 2004

21 Costamagna et al Gastroenterology 2002

22 Capsule Endoscopy vs SBFT 13 patients with obscure-overt overt GI bleeding. Capsule endoscopy made a definite diagnosis in 4 (31%). 1 (8%) with SBFT. Costamagna et al Gastroenterology 2002

23 Pennazio et al Gastroenterology 2004

24 Ell C et al Endoscopy 2002

25 Ell C et al Endoscopy 2002

26 Limitations of Capsule Endoscopy Neither Biopsy, nor hemostatic therapy,nor endoscopic marking is possible. All of the intestinal mucosa is not visualized: debris, imaging cannot be controlled. Not all examination reach the ileocecal valve. Precise location of lesions cannot be determined. Patients with cardiac pacemakers or defibrillators or those with potential GI tract obstruction.

27 Yamamoto H et al Gastrointest Endoscopy 2001 Double-Balloon Enteroscopy

28 Double-Balloon Enteroscopy Yamamoto H et al Gastrointest Endoscopy 2001

29 Double-Balloon Enteroscopy Yamamoto H et al Gastrointest Endoscopy 2001

30 Double-Balloon Enteroscopy Limited clinical experience. Potential limitations in visualizing the entire small bowel. Miss subepithial lesions due to insufflation. Potential complications.

31 Exploratory Laparotomy With Intraoperative Enteroscopy Zaman A et al Gastrointest endosc 1999

32 Exploratory Laparotomy With Intraoperative Enteroscopy Zaman A et al Gastrointest endosc 1999

33 Exploratory Laparotomy With Intraoperative Enteroscopy Allow for hemostatic therapy Identification of lesions for definite surgical resection. Reported complications : mucosal lacerations, perforations, prolonged ileus, abdominal abscess, and bowel ischemia.

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35 Conclusions Up to 5% of overt GI hemorrhage will have negative upper endoscopy and colonosocopy. There is no single uniform diagnostic approach for obscure GI bleeding; push enteroscopy,, repeat colonoscopy with retrograde evaluation of the terminal ileum, capsule endoscopy,, and possible exploratory laparotomy with intraoperative endoscopy is often warranted. UGI series with SBFT, enteroclysis,, tagged RBC, mesenteric angiography have a limited role in the diagnostic evaluation of obscure GI bleeding. Future technological advances such as double-balloon balloon enteroscopy remain to be fully evaluated