GI- Bleeding

The most common causes of occult bleeding with iron deficiency are

(1) neoplasms; (2) vascular abnormalities (angioectasias); (3) acid-peptic lesions (esophagitis, peptic ulcer disease, erosions in hiatal hernia); (4) infections (nematodes, especially hookworm; tuberculosis); (5) medications (especially NSAIDs or aspirin); and (6) other causes such as inflammatory bowel disease

Anorectal disease

(hemorrhoids, fissures) usually results in small amounts of bright red blood noted on the toilet paper, streaking of the stool, or dripping into the toilet bowl; clinically significant blood loss can sometimes occur. Hemorrhoids are the source in 10% of patients admitted with lower bleeding. Rectal ulcers may account for up to 8% of lower bleeding, usually in elderly or debilitated patients with constipation

black stools

(melena) predict a source proximal to the ligament of Treitz

patients under age 30

A nuclear scan for Meckel diverticulum should be obtained

In patients with significant bleeding

two 18-gauge or larger intravenous lines should be started prior to further diagnostic tests. Blood is sent for complete blood count, prothrombin time with international normalized ratio (INR), serum creatinine, liver enzymes, and blood typing and screening (in anticipation of need for possible transfusion)

Diverticular bleeding

usually presents as acute, painless, large-volume maroon or bright red hematochezia in patients over age 50 years. More than 95% of cases require < 4 units of blood transfusion. Bleeding subsides spontaneously in 80% but may recur in up to 25% of patients.

Low to moderate risk pts

All other patients are admitted to a step-down unit or medical ward after appropriate stabilization for further evaluation and treatment. Patients without evidence of active bleeding undergo nonemergent endoscopy usually within 24 hours

Painless large-volume bleeding

usually suggests diverticular bleeding

Hct

Because the may take 24-72 hours to equilibrate with the extravascular fluid, it is not a reliable indicator of the severity of acute bleeding.

Portal hypertension

Bleeding usually arises from esophageal varices and less commonly gastric or duodenal varices or portal hypertensive gastropathy

Anoscopy and sigmoidoscopy

In otherwise healthy patients without anemia under age 45 years with small-volume bleeding, anoscopy and sigmoidoscopy are performed to look for evidence of anorectal disease, inflammatory bowel disease, or infectious colitis. If a lesion is found, no further evaluation is needed immediately unless the bleeding persists or is recurrent. In patients over age 45 years with small-volume hematochezia, the entire colon must be evaluated with colonoscopy to exclude tumor.

Acute Upper Gastrointestinal Bleeding

Hematemesis (bright red blood or "coffee grounds"). Melena in most cases; hematochezia in massive upper gastrointestinal bleeds. Volume status to determine severity of blood loss; hematocrit is a poor early indicator of blood loss. Endoscopy diagnostic and may be therapeutic.

Acute Lower Gastrointestinal Bleeding

Hematochezia usually present. Ten percent of cases of hematochezia due to upper gastrointestinal source. Evaluation with colonoscopy in stable patients. Massive active bleeding calls for evaluation with sigmoidoscopy, upper endoscopy, angiography, or nuclear bleeding scan.

Assessment of GI bleed

Hemodynamic status! SBP < 100 mm Hg = a high-risk patient with severe acute bleeding. HR>100 beats/min with SBP>100 mm Hg signifies moderate acute blood loss. Normal SBP & HR suggest relatively minor hemorrhage. Postural hypotension and tachycardia are useful when present but may be due to causes other than blood loss.

Diverticulitis

Hemorrhage occurs in 3-5% of all patients with diverticulosis and is the most common cause of major lower tract bleeding, accounting for 50% of cases (see endoscopy). increased risk of diverticular hemorrhage among patients who use aspirin or nonsteroidal anti-inflammatory agents

Therapeutic colonoscopy

High-risk lesions (eg, angioectasias or diverticulum, rectal ulcer with active bleeding, or a visible vessel) may be treated endoscopically with epinephrine injection, cautery (bipolar or heater probe), or application of metallic endoclips or bands. In diverticular hemorrhage with high-risk lesions identified at colonoscopy, rebleeding occurs in half of untreated patients compared with virtually no rebleeding in patients treated endoscopically. Radiation proctitis is effectively treated with applications of cautery therapy to the rectal telangiectasias, preferably with an argon plasma coagulator

Colonoscopy

In patients with acute, large-volume bleeding requiring hospitalization, colonoscopy is the preferred initial study in most cases. The bowel first is purged rapidly by administration of a high-volume colonic lavage solution, given until the effluent is clear of blood and clots (4-10 L of GoLYTELY, CoLYTE, NuLYTE given orally or 1 L every 30 minutes over 2-5 hours by nasogastric tube). For patients with stable vital signs and whose lower gastrointestinal bleeding appears to have stopped, colonoscopy can be performed electively within 24 hours of admission. For patients with signs of hemodynamically significant bleeding (unstable vital signs) or who have signs of continued active bleeding during bowel preparation, urgent colonoscopy should be performed within 1-2 hours of completing the bowel purgative, when the bowel discharge is without clots. The probable site of bleeding can be identified in 70-85% of patients, and a high-risk lesion can be identified and treated in up to 20%.

Tx for Lower GI bleed

Initial stabilization, blood replacement, and triage are managed in the same manner as described above for Acute Upper Gastrointestinal Bleeding

Other Tx

Intra-arterial embolization Transvenous intrahepatic portosystemic shunts (TIPS)

Acute pharm therapies

Intravenous proton pump inhibitors Oral proton pump inhibitors Octreotide (potent inhibitor of growth hormone, glucagon, and insulin than the natural hormone): reduces splanchnic blood flow and portal blood pressures and is effective

MALLORY-WEISS TEARS

Lacerations of the gastroesophageal junction Many patients report a history of heavy alcohol use or retching.

Transvenous intrahepatic portosystemic shunts (TIPS)

Placement of a wire stent from the hepatic vein through the liver to the portal vein provides effective decompression of the portal venous system and control of acute variceal bleeding. It is indicated in patients in whom endoscopic modalities have failed to control acute variceal bleeding.

Nuclear bleeding scans and angiography

Technetium-labeled red blood cell scanning can detect significant active bleeding and, in some cases, can localize the source to the small intestine, right colon, or left colon. Thus, some physicians obtain a nuclear bleeding scan to guide initial decision-making. If no bleeding is detected on scintigraphy, an "elective" colonoscopy is performed within 24 hours after conventional bowel preparation. If bleeding is detected on scintigraphy, urgent angiography is performed instead of colonoscopy. Nuclear studies are more apt to be positive in patients who are passing bright red or maroon stools at the time of the scan. Because most bleeding is slow or intermittent, less than half of nuclear studies are diagnostic and the accuracy of localization is poor. Thus, the main utility of scintigraphy is to determine whether bleeding is ongoing in order to determine whether angiography should be pursued. Less than half of patients with a positive nuclear study have positive angiography. Accordingly, angiograms are performed only in patients with positive technetium scans believed to have significant, ongoing bleeding. In patients with massive lower gastrointestinal bleeding manifested by continued hemodynamic instability and hematochezia, urgent angiography should be performed without attempt at colonoscopy or scintigraphy.

Small Intestine Push Enteroscopy or Capsule Imaging

Up to 5% of acute episodes of lower gastrointestinal bleeding arise from the small intestine, eluding diagnostic evaluation with upper endoscopy and colonoscopy. Because of the difficulty of examining the small intestine and its relative rarity as a source of acute bleeding, evaluation of the small bowel is not usually pursued in patients during the initial episode of acute lower gastrointestinal bleeding. However, the small intestine is investigated in patients with unexplained recurrent hemorrhage of obscure origin.

In an older patient with significant comorbid illnesses, no gastrointestinal symptoms, and occult or obscure bleeding in whom the suspected source of bleeding is angioectasias

may be reasonable to limit diagnostic evaluations, provided the anemia can be managed with long-term iron therapy or occasional transfusions.

occult bleeding in an adult is identified by

a positive FOBT, FIT, or iron deficiency anemia in the absence of visible blood loss. FOBT or FIT may be performed in patients with gastrointestinal symptoms or as a screening test for colorectal neoplasia

High risk pts

active bleeding manifested by hematemesis or bright red blood on nasogastric aspirate, shock, persistent hemodynamic derangement despite fluid resuscitation, serious comorbid medical illness, or evidence of advanced liver disease require admission to an intensive care unit (ICU). After adequate resuscitation, endoscopy should be performed within 2-24 hours may be delayed in selected patients with serious comorbidities (eg, acute coronary syndrome) who do not have signs of continued bleeding.

Clinical predictors of increased risk of rebleeding and death

age > 60 years, comorbid illnesses, systolic blood pressure < 100 mm Hg, pulse > 100 beats/min, and bright red blood in the nasogastric aspirate or on rectal examination

in younger patients with obscure bleeding and symptomatic older patients with overt or obscure bleeding

aggressive diagnostic evaluation is warranted Upper endoscopy and colonoscopy should be repeated to ascertain that a lesion in these regions has not been overlooked If these studies are unrevealing, capsule endoscopy should be performed to evaluate the small intestine.

In patients without hemodynamic compromise or overt active bleeding

aggressive fluid repletion can be delayed until the extent of the bleeding is further clarified

In the colon, the most commonly overlooked lesions are

angioectasias and neoplasms.

Dx tests

anoscopy and sigmoidoscopy, colonoscopy, nuclear bleeding scans and angiography, and small intestine push enteroscopy or capsule imaging.

Patients with evidence of hemodynamic compromise

are given 0.9% saline or lactated Ringer injection and cross-matched for 2-4 units of packed red blood cells. Rarely necessary to administer type-specific or O-negative blood. Central venous pressure monitoring is desirable in some cases, but line placement should not interfere with rapid volume resuscitation.

In patients under 50 years of age, the most common causes

are infectious colitis, anorectal disease, and inflammatory bowel disease.

The most common causes of small intestinal bleeding in patients younger than 40

are neoplasms (stromal tumors, lymphomas, adenocarcinomas, carcinoids) Crohn disease, celiac disease, and Meckel diverticulum

Obscure bleeding (either occult or overt) most commonly

arises from lesions in the small intestine. In up to one-third of cases, however, a source of bleeding has been overlooked in the upper or lower tract on prior endoscopic studies

Benign polyps and carcinoma

associated with chronic occult blood loss or intermittent anorectal hematochezia In general, prompt colonoscopy is recommended to treat postpolypectomy hemorrhage and minimize the need for transfusions.

amount of fluid and blood products

based on assessment of vital signs, evidence of active bleeding from nasogastric aspirate, and laboratory tests. Sufficient packed red blood cells should be given to maintain a hemoglobin of 6-10 g/dL, based on the patient's hemodynamic status, comorbidities (especially cardiovascular disease), and presence of continued bleeding.

Etiology lower GI bleeds

cause of these lesions depends on both the age of the patient and the severity of the bleeding

Bloody diarrhea associated with cramping abdominal pain, urgency, or tenesmu

characteristic of inflammatory bowel disease, infectious colitis, or ischemic colitis.

Ischemic colitis

commonly in older patients, most of whom have atherosclerotic disease. Most cases occur spontaneously due to transient episodes of nonocclusive ischemia In most patients, the bleeding is mild and self-limited.

Evaluation of obscure bleeding

depends on the age and overall health status of the patient, associated symptoms, and severity of the bleeding

Melena

develops after as little as 50-100 mL of blood loss in the upper gastrointestinal tract, whereas hematochezia requires a loss of more than 1000 mL. Although hematochezia generally suggests a lower bleeding source (eg, colonic), severe upper gastrointestinal bleeding may present with hematochezia in 10% of cases.

Vascular anomalies

found throughout the gastrointestinal tract and may be the source of chronic or acute gastrointestinal bleeding. most common are angioectasias telangiectasias

most common presentation of upper gastrointestinal bleeding

hematemesis or melena is self-limited in 80% of patients; urgent medical therapy and endoscopic evaluation are obligatory in the rest

In the absence of continued bleeding

hemoglobin should rise approximately 1 g/dL for each unit of transfused packed red cells. Transfusion of blood should not be withheld from patients with brisk active bleeding regardless of the hemoglobin value. It is desirable to transfuse blood in anticipation of the nadir hematocrit

Large volumes of bright red blood

suggest a colonic source

Lower gastrointestinal bleeding is defined as

that arising below the ligament of Treitz, ie, the small intestine or colon; however, up to 95% of cases arise from the colon

maroon stools

imply a lesion in the right colon or small intestine

Capsule endoscopy

is superior to radiographic studies (standard small bowel follow through, enteroclysis, or CT enterography) and standard push enteroscopy for the detection of small bowel abnormalities, demonstrating possible sources of occult bleeding in 60% of patients, most commonly vascular abnormalities (30%), ulcers (25%), and neoplasms (< 1-5%). Further management depends on the capsule endoscopic findings

Laparotomy

is warranted if a small bowel tumor is identified by capsule endoscopy or radiographic studies

Etiology-Acute upper gastrointestinal bleeding

listed in order of their frequency and discussed in detail below: PEPTIC ULCER DISEASE PORTAL HYPERTENSION MALLORY-WEISS TEARS VASCULAR ANOMALIES GASTRIC NEOPLASMS EROSIVE GASTRITIS EROSIVE ESOPHAGITIS

Obscure-overt bleeding

manifested by persistent or recurrent visible evidence of gastrointestinal bleeding (hematemesis, hematochezia, or melena).

Abdominal CT

may be considered to exclude a hepatic or pancreatic source of bleeding

Hematemesis

may be either bright red blood or brown "coffee grounds" material

Serious lower gastrointestinal bleeding

more common in older men

In older patients

most often seen with diverticulosis, angiectasias, malignancy, or ischemia.

Exclusion of upper tract source

nasogastric tube with aspiration should be considered, especially in patients with hemodynamic compromise. Aspiration of red blood or dark brown ("coffee grounds") guaiac-positive material strongly implicates an upper gastrointestinal source of bleeding. Upper endoscopy should be performed in most patients presenting with hematochezia and hemodynamic instability to exclude an upper gastrointestinal source before proceeding with evaluation of the lower gastrointestinal tract.

Angiectasias (angiodysplasias)

occur throughout the upper and lower intestinal tracts and cause painless bleeding ranging from melena or hematochezia to occult blood loss most often seen in the cecum and ascending colon. They are flat, red lesions most common in patients over 70 years and in those with chronic renal failure. Bleeding in younger patients more commonly arises from the small intestine

inflammatory bowel disease

often have diarrhea with variable amounts of hematochezia Bleeding varies from occult blood loss to recurrent hematochezia usually mixed with stool. Symptoms of abdominal pain, tenesmus, and urgency are often present.

diverticula are more prevalent

on the left side of the colon, bleeding more commonly originates on the right side.

In actively bleeding patients

platelets are transfused if the platelet count is under 50,000/mcL and considered if there is impaired platelet function due to aspirin or clopidogrel use (regardless of the platelet count).

Brown stools mixed or streaked with blood

predict a source in the rectosigmoid or anus.

Obscure gastrointestinal bleeding

refers to bleeding of unknown origin that persists or recurs after initial endoscopic evaluation with upper endoscopy and colonoscopy

Obscure-occult bleeding

refers to bleeding that is not apparent to the patient. It is manifested by recurrent positive FOBTs or FITs or recurrent iron deficiency anemia, or both in the absence of visible blood loss (as described below).

Gastric neoplasms

result in 1% of upper gastrointestinal hemorrhages

Patients with iron deficiency anemia

should be evaluated for possible celiac disease with either IgA anti-tissue transglutaminase or duodenal biopsy

Asymptomatic adults with positive FOBTs or FITs

should undergo colonoscopy

All symptomatic adults with positive FOBTs or FITs or iron deficiency anemia

should undergo evaluation of the upper and lower gastrointestinal tract with colonoscopy and upper endoscopy, unless the anemia can be definitively ascribed to a nongastrointestinal source (eg, menstruation, blood donation, or recent surgery).

Virtually all patients with upper tract bleeding

should undergo upper endoscopy within 24 hours of arriving in the emergency department.

Bright red blood that drips into the bowl after a bowel movement or is mixed with solid brown stool

signifies mild bleeding, usually from an anorectosigmoid source, and can be evaluated in the outpatient setting.