Radiologic Management of Lower Gastrointestinal Tract Bleeding

Variant: 1 Lower gastrointestinal tract bleeding. Active bleeding clinically observed as hematochezia or melena in a hemodynamically stable patient. Next step.

Procedure	Appropriateness Category
CTA abdomen and pelvis without and with IV contrast	Usually Appropriate
Diagnostic/therapeutic colonoscopy	Usually Appropriate
RBC scan abdomen and pelvis	Usually Appropriate
Transcatheter arteriography/embolization	May Be Appropriate
MRA abdomen and pelvis without and with IV contrast	Usually Not Appropriate
Surgery	Usually Not Appropriate

Variant: 2 Lower gastrointestinal tract bleeding. Active bleeding in a hemodynamically unstable patient or a patient who has required more than 5 units of blood within 24 hours. Next step.

Procedure	Appropriateness Category
CTA abdomen and pelvis without and with IV contrast	Usually Appropriate
Transcatheter arteriography/embolization	Usually Appropriate
Diagnostic/therapeutic colonoscopy	May Be Appropriate (Disagreement)
Surgery	May Be Appropriate
RBC scan abdomen and pelvis	Usually Not Appropriate
MRA abdomen and pelvis without and with IV contrast	Usually Not Appropriate

Variant: 3 Lower gastrointestinal tract bleeding. Colonoscopy localized the bleeding site and treatment was attempted. Ongoing or recurrent bleeding. Next procedure or intervention.

Procedure	Appropriateness Category
Transcatheter arteriography/embolization	Usually Appropriate
Surgery	May Be Appropriate
CTA abdomen and pelvis without and with IV contrast	May Be Appropriate (Disagreement)
Diagnostic/therapeutic colonoscopy	May Be Appropriate (Disagreement)
MRA abdomen and pelvis without and with IV contrast	Usually Not Appropriate
RBC scan abdomen and pelvis	Usually Not Appropriate

Variant: 4 Lower gastrointestinal tract bleeding. Transcatheter arteriography localized the bleeding site and treatment was attempted. Ongoing or recurrent bleeding. No other prior radiological or endoscopic investigations. Next procedure or intervention.

Procedure	Appropriateness Category
Diagnostic/therapeutic colonoscopy	Usually Appropriate
CTA abdomen and pelvis without and with IV contrast	May Be Appropriate
Surgery	May Be Appropriate
Transcatheter arteriography/embolization	May Be Appropriate
MRA abdomen and pelvis without and with IV contrast	Usually Not Appropriate
RBC scan abdomen and pelvis	Usually Not Appropriate

Variant: 5 Lower gastrointestinal tract bleeding. Obscure (nonlocalized) recurrent bleeding in a hemodynamically stable patient (assumes a prior negative adequate colonoscopy and upper gastrointestinal endoscopy). Next procedure or intervention.

Procedure	Appropriateness Category
Capsule endoscopy	Usually Appropriate
CT enterography abdomen and pelvis with IV contrast	Usually Appropriate
RBC scan abdomen and pelvis	May Be Appropriate
RBC scan with SPECT or SPECT/CT abdomen and pelvis	May Be Appropriate
Push enteroscopy	May Be Appropriate
Transcatheter arteriography/embolization	May Be Appropriate (Disagreement)
MR enterography	May Be Appropriate
Surgery	Usually Not Appropriate
Fluoroscopy small bowel follow-through	Usually Not Appropriate

Panel Members

Baljendra S. Kapoor, MD^a; Karunakaravel Karuppasamy, MD, MSc^b; Nicholas Fidelman, MD^c; Hani Abujudeh, MD, MBA^d; Twyla B. Bartel, DO, MBA^e; Drew M. Caplin, MD^f; Brooks D. Cash, MD^g; Steven J. Citron, MD^h; Khashayar Farsad, MD, PhDⁱ; Aakash H. Gajjar, MD^j; Marcelo S. Guimaraes, MD^k; Amit Gupta, MD^l; Mikhail C.S.S. Higgins, MD, MPH^m; Daniele Marin, MDⁿ; Parag J. Patel, MD^o; Jason A. Pietryga, MD^p; Paul J. Rochon, MD^q; Kevin S. Stadtlander, MD^r; Pal S. Suranyi, MD, PhD^s; Jonathan M. Lorenz, MD^t.

Summary of Literature Review

Introduction/Background

Special treatment considerations

Discussion of Procedures by Variant

Variant 1: Lower gastrointestinal tract bleeding. Active bleeding clinically observed as hematochezia or melena in a hemodynamically stable patient. Next step.

Variant 1: Lower gastrointestinal tract bleeding. Active bleeding clinically observed as hematochezia or melena in a hemodynamically stable patient. Next step.
A. CTA abdomen and pelvis without and with IV contrast

Variant 1: Lower gastrointestinal tract bleeding. Active bleeding clinically observed as hematochezia or melena in a hemodynamically stable patient. Next step.
B. Diagnostic/therapeutic colonoscopy

Variant 1: Lower gastrointestinal tract bleeding. Active bleeding clinically observed as hematochezia or melena in a hemodynamically stable patient. Next step.
C. MRA abdomen and pelvis without and with IV contrast

Variant 1: Lower gastrointestinal tract bleeding. Active bleeding clinically observed as hematochezia or melena in a hemodynamically stable patient. Next step.
D. RBC scan abdomen and pelvis

Variant 1: Lower gastrointestinal tract bleeding. Active bleeding clinically observed as hematochezia or melena in a hemodynamically stable patient. Next step.
E. Surgery

Variant 1: Lower gastrointestinal tract bleeding. Active bleeding clinically observed as hematochezia or melena in a hemodynamically stable patient. Next step.
F. Transcatheter arteriography/embolization

Variant 2: Lower gastrointestinal tract bleeding. Active bleeding in a hemodynamically unstable patient or a patient who has required more than 5 units of blood within 24 hours. Next step.

Variant 2: Lower gastrointestinal tract bleeding. Active bleeding in a hemodynamically unstable patient or a patient who has required more than 5 units of blood within 24 hours. Next step.
A. CTA abdomen and pelvis without and with IV contrast

Variant 2: Lower gastrointestinal tract bleeding. Active bleeding in a hemodynamically unstable patient or a patient who has required more than 5 units of blood within 24 hours. Next step.
C. MRA abdomen and pelvis without and with IV contrast

Variant 3: Lower gastrointestinal tract bleeding. Colonoscopy localized the bleeding site and treatment was attempted. Ongoing or recurrent bleeding. Next procedure or intervention.

Variant 3: Lower gastrointestinal tract bleeding. Colonoscopy localized the bleeding site and treatment was attempted. Ongoing or recurrent bleeding. Next procedure or intervention.
A. CTA abdomen and pelvis without and with IV contrast

Variant 3: Lower gastrointestinal tract bleeding. Colonoscopy localized the bleeding site and treatment was attempted. Ongoing or recurrent bleeding. Next procedure or intervention.
C. MRA abdomen and pelvis without and with IV contrast

Variant 4: Lower gastrointestinal tract bleeding. Transcatheter arteriography localized the bleeding site and treatment was attempted. Ongoing or recurrent bleeding. No other prior radiological or endoscopic investigations. Next procedure or intervention.

Variant 5: Lower gastrointestinal tract bleeding. Obscure (nonlocalized) recurrent bleeding in a hemodynamically stable patient (assumes a prior negative adequate colonoscopy and upper gastrointestinal endoscopy). Next procedure or intervention.

Summary of Highlights

Supporting Documents

The evidence table, literature search, and appendix for this topic are available at https://acsearch.acr.org/list. The appendix includes the strength of evidence assessment and the final rating round tabulations for each recommendation.

For additional information on the Appropriateness Criteria methodology and other supporting documents, please go to the ACR website at https://www.acr.org/Clinical-Resources/Clinical-Tools-and-Reference/Appropriateness-Criteria.

Appropriateness Category Names and Definitions

Appropriateness Category Name	Appropriateness Rating	Appropriateness Category Definition
Usually Appropriate	7, 8, or 9	The imaging procedure or treatment is indicated in the specified clinical scenarios at a favorable risk-benefit ratio for patients.
May Be Appropriate	4, 5, or 6	The imaging procedure or treatment may be indicated in the specified clinical scenarios as an alternative to imaging procedures or treatments with a more favorable risk-benefit ratio, or the risk-benefit ratio for patients is equivocal.
May Be Appropriate (Disagreement)	5	The individual ratings are too dispersed from the panel median. The different label provides transparency regarding the panel’s recommendation. “May be appropriate” is the rating category and a rating of 5 is assigned.
Usually Not Appropriate	1, 2, or 3	The imaging procedure or treatment is unlikely to be indicated in the specified clinical scenarios, or the risk-benefit ratio for patients is likely to be unfavorable.

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Disclaimer

The ACR Committee on Appropriateness Criteria and its expert panels have developed criteria for determining appropriate imaging examinations for diagnosis and treatment of specified medical condition(s). These criteria are intended to guide radiologists, radiation oncologists and referring physicians in making decisions regarding radiologic imaging and treatment. Generally, the complexity and severity of a patient’s clinical condition should dictate the selection of appropriate imaging procedures or treatments. Only those examinations generally used for evaluation of the patient’s condition are ranked. Other imaging studies necessary to evaluate other co-existent diseases or other medical consequences of this condition are not considered in this document. The availability of equipment or personnel may influence the selection of appropriate imaging procedures or treatments. Imaging techniques classified as investigational by the FDA have not been considered in developing these criteria; however, study of new equipment and applications should be encouraged. The ultimate decision regarding the appropriateness of any specific radiologic examination or treatment must be made by the referring physician and radiologist in light of all the circumstances presented in an individual examination.