Lower gastrointestinal bleeding

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Lower gastrointestinal bleeding
Other namesLGIB
A positive fecal occult blood test
SpecialtyGastroenterology Edit this on Wikidata
Symptomsbright blood in stool dark blood in vomit

Lower gastrointestinal bleeding, commonly abbreviated LGIB, is any form of

lower gastrointestinal tract. LGIB is a common reason for seeking medical attention at a hospital's emergency department.[1] LGIB accounts for 30–40% of all gastrointestinal bleeding and is less common than upper gastrointestinal bleeding (UGIB).[2] It is estimated that UGIB accounts for 100–200 per 100,000 cases versus 20–27 per 100,000 cases for LGIB.[3] Approximately 85% of lower gastrointestinal bleeding involves the colon, 10% are from bleeds that are actually upper gastrointestinal bleeds, and 3–5% involve the small intestine.[4]

Signs and symptoms

A lower gastrointestinal bleed is defined as bleeding originating distal to the

ligament of Treitz, which included the aforementioned parts of the intestine and also included the last 1/4 of the duodenum and the entire area of the jejunum and ileum.[1] This has been divided into middle gastrointestinal bleeding (from the ligament of Treitz to the ileocecal valve) and lower gastrointestinal bleeding which involves a bleed anywhere from the ileocecal valve to the anus.[2]

The

proximal colon.[5] Bright red stool, called hematochezia, is the sign of a fast moving active GI bleed.[1] The bright red or maroon color is due to the short time taken from the site of the bleed and the exiting at the anus. The presence of hematochezia is six-times greater in a LGIB than with a UGIB.[5]

Occasionally, a person with a LGIB will not present with any signs of internal bleeding, especially if there is a chronic bleed with ongoing low levels of blood loss. In these cases, a diagnostic assessment or pre-assessment should watch for other signs and symptoms that the patient may present with. These include, but are not limited to,

heart attack, and shock
.

Causes

The following are possible causes of a LGIB:

Diagnosis

Diverticular disease – a cause of LGIBs

Diagnostic evaluation must be performed after patients have been adequately resuscitated. If an upper GI source is suspected, an

radiologic studies.[6]

History

The history in these patients should focus on factors that could be associated with potential causes: blood coating the stool suggests hemorrhoidal bleeding while blood mixed in the stool implies a more proximal source; bloody diarrhea and tenesmus is associated with

colon cancer; abdominal pain can be associated with inflammatory bowel disease, infectious colitis, or ischemic colitis; painless bleeding is characteristic of diverticular bleeding, arteriovenous malformation (AVM), and radiation proctitis; nonsteroidal anti-inflammatory drug (NSAID) use is a risk factor for diverticular bleeding and NSAID-induced colonic ulcer; and recent colonoscopy with polypectomy suggests postpolypectomy bleeding. Patients should be asked about symptoms of hemodynamic compromise, including dyspnea, chest pain, lightheadedness, and fatigue.[7]

Physical findings

Orthostatic hypotension implies at least a 15% loss of blood volume and suggests a more severe bleeding episode. Evaluate for abdominal tenderness, masses, and enlargement of the liver and spleen. Additional key elements include a careful and thorough inspection of the anus, palpation for rectal masses, characterization of the stool color, and a stool guaiac card test to evaluate for the presence of blood.[citation needed]

Laboratory findings

Among the blood tests that should be performed are a

electrolytes, and typing and cross-matching for transfusion of blood products.[8]
A
hemophilia A and B with factor VIII and IX inhibitors. Evidence of possible benefit in patients with cirrhosis and GI bleeding has been demonstrated, although the optimal dose is unclear and recombinant activated factor VII is very expensive.[6]

Anoscopy

Anoscopy is useful only for diagnosing bleeding sources from the anorectal junction and anal canal, including internal

hemorrhoids and anal fissures. It is superior to flexible sigmoidoscopy for detecting hemorrhoids in an outpatient setting and can be performed quickly in the office or at the bedside as an adjunct to flexible sigmoidoscopy and colonoscopy.[citation needed
]

Flexible sigmoidoscopy

Flexible sigmoidoscopy uses a 65-cm long sigmoidoscope that visualizes the left colon. It can be performed without sedation and only minimal preparation with enemas. However, the diagnostic yield of flexible sigmoidoscopy in acute lower GI bleeding is only 9%. The role of anoscopy and flexible sigmoidoscopy in inpatients with acute lower GI bleeding is limited, as most patients should undergo colonoscopy.[citation needed
]

Colonoscopy

Colonoscopy is the test of choice in the majority of patients with acute Lower GI bleeding as it can be both diagnostic and therapeutic. The diagnostic accuracy of colonoscopy in lower GI bleeding ranges from 48% to 90%, and urgent colonoscopy appears to increase diagnostic yield. This wide range in yield is partially explained by different criteria for diagnosis, as often if no active bleeding, nonbleeding visible vessel, or adherent clot is found, bleeding is attributed to a lesion if blood is present in the area. The presence of fresh blood in the

terminal ileum
is presumed to indicate a non colonic source of bleeding. The overall complication rate of colonoscopy in acute lower GI bleeding is 1.3%. Bowel preparation is safe and well tolerated in most patients. The complication rate of colonoscopy in an unprepped colon may be higher. About 2–6% of colonoscopy preparations in acute lower GI bleeding are poor. Between 4 and 8 L of Golytely should be administered orally or via nasogastric tube until the effluence is clear.[9]

Management

Basic algorithm for the management of lower GI bleed.

In most cases requiring emergency hospital admission, the bleeding will resolve spontaneously.[2][10] If a patient is suspected of having severe blood loss they will most likely be placed on a vital sign monitor and administered oxygen either by nasal cannula or simple face mask. An intravenous catheter will be placed into an easily accessible area and IV fluids will be administered to replace lost blood volume.[1] Endoscopic evaluation with a colonoscopy (and possibly an esophagogastroduodenoscopy to exclude an UGIB) should typically occur within 24 hours of hospital presentation.[2]

If the person with LGIB is on low-dose

Dual antiplatelet therapy (e.g., use of both aspirin and clopidogrel) should continue if the person with a LGIB underwent stenting of the heart's coronary arteries within the last 30 days or a recent acute coronary syndrome episode (e.g., unstable angina or a myocardial infarction) within 90 days of the LGIB event.[2] Individuals at high risk of another heart attack but not meeting the above criteria should continue their aspirin during the LGIB event but stop the other antiplatelet medication for 1–7 days following cessation of the bleed.[2]

Predicting which patients will develop adverse outcomes, complications or severe bleeding can be difficult. One recent study identified poor kidney function (creatinine > 150 μm), age over 60 years, abnormal haemodynamic parameters on presentation (low blood pressure) and persistent bleeding within the first 24 hours as risk factors for worse outcome.[10]

Surgical intervention is warranted in cases of LGIB that persist despite attempts to stop the bleeding with endoscopic or interventional radiology interventions.[2] It is most likely that a surgical consult will be ordered if the patient is unable to be stabilized by non-invasive techniques, or if a perforation is found that requires surgery (e.g., subtotal removal of the colon).[1]

References

  1. ^
    ISBN 0-7817-5125-X
    .
  2. ^
    S2CID 44539833
    .
  3. PMID 11432297
    .
  4. PMID 18851756
    .
  5. ^
    PMID 9177503
    .
  6. ^
    PMID 12695275
    .
  7. S2CID 25632485
    .
  8. PMID 15181617
    .
  9. S2CID 20881020
    .
  10. ^
    S2CID 26514078
    .

External links
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