Gastrointestinal Hemorrhage

ACUTE GASTROINTESTINAL HEMORRHAGE Acute gastrointestinal (GI) bleeding remains a common major medical problem despite recent advances in diagnosis and treatment the overall mortality rate from acute bleeding episodes has remained essentially unchanged during the past half-century, owing to an aging population and an increased prevalence of serious concomitant illnesses.

Clinical Presentation Significant GI bleeding typically manifests with some combination of weakness, dizziness, lightheadedness, shortness of breath, postural changes in blood pressure or pulse, cramping abdominal pain, diarrhea and bleeding from GI

GIB: Overt or Occult bleeding Overt GIB: visible blood loss from GI Occult bleeding: subacute or not clinically visible & absence of overt bleeding Patients present with symptoms of blood loss or anemia such as lightheadedness, syncope, angina, dyspnea in routine diagnostic evaluation reveals IDA ,positive fecal occult blood test

Obscure GIB: source is unclear(not apparent after EGD & Colonoscopy) Upper GI.bleeding or lower Gi.bleeding or obscure GIB Upper: proximal treitz ligamentsss Lower: distal treitz ligament UGIB ~1.5–2 times more common than LGIBs Obscure GIB: source is unclear(not apparent after EGD & Colonoscopy)

Severe GI bleeding Hematemesis, melena, hematochezia, or positive nasogastric lavage accompanied by shock or orthostatic hypotension, ↓ Hct ≥6% or ↓Hb ≥ 2 g/dL or transfusion of at least 2 units of P/C

Hematemesis The patient vomits bright red blood(recent or ongoing bleeding) or coffee grounds(stopped some time ago) After exclusion of swallowed blood from the nasopharynx or the respiratory tract (hemoptysis), the source of bleeding is likely to be proximal to the ligament of Treitz

Melena Black, tarry, usually foul-smelling stools are most often a manifestation of upper GI bleeding(>90%) ; however, a small bowel or proximal colonic source of bleeding may on occasion lead to melenic stools(>10-14hours in bowel) Volumes as little as 50 to 100 mL of blood in the stomach can result in melena.

Hematochezia The passage of bright-red blood or maroon stools per rectum frequently indicates a L.GI.B However, 10% to 15% of patients with acute severe hematochezia have an upper GI source of brisk bleeding. This group of patients commonly displays signs of hemodynamic instability

Etiology Distinguish between upper and lower GI is a major goal …. management strategies are different The symptoms, the history and physical examination, the age of the patient, and results of laboratory studies may be effective In many patients, the site of bleeding frequently remains uncertain after the initial evaluation.

Approach to the Patient with Acute Gastrointestinal Bleeding Assessment of Vital Signs and Resuscitation A simple manner for the approach to gastrointestinal bleeding is SET: Stabilization, Evaluation (endoscopy), and Treatment

Vital signs with postural changes should be recorded immediately If the systolic blood pressure drops more than 10 mm Hg or the pulse increases more than 10 beats per minute as the patient changes position from supine to standing, it is likely the patient has lost at least 800 mL (15%) of circulating blood volume.

Hypotension, tachycardia, tachypnea, and mental status changes in the setting of acute GI hemorrhage suggest the loss of at least 1500 mL (30%) of circulating blood volume.

The goals of resuscitation are to restore the normal circulatory volume and to prevent complications from blood loss, such as cardiac, pulmonary, renal, or neurologic consequences Initially, at least two large-bore intravenous catheters are used to administer isotonic solutions (e.g., lactated Ringer’s solution, 0.9% NaCl), and blood products if indicated

If the patient is in shock …. central venous access(CVP line) If coagulation studies are abnormal, as is commonly observed in cirrhotic patients …. fresh frozen plasma, platelets, or both may be required to control ongoing hemorrhage

Initial Evaluation While resuscitation is underway, the following information should be obtained by history and P/E to determine the source of bleeding 1. The nature of the bleeding: melena, hematemesis, hematochezia, or occult blood

A digital rectal examination is essential for determination of stool color and identification of anal fissures or rectal neoplasms 2. The duration of GI bleeding, which helps dictate the appropriate pace of the evaluation to determine the bleeding source .

3. The presence or absence of abdominal pain for example, hematochezia caused by diverticula or angiodysplasia typically is painless but hematochezia due to intestinal ischemia is often accompanied by abdominal pain.

4. Other associated symptoms, including fever, urgency or tenesmus, recent change in bowel habits and weight loss 5. Current or recent medication use, particularly nonsteroidal anti-inflammatory drugs (NSAIDs), including aspirin, which may predispose to ulceration or gastritis , anticoagulants, and alcohol

6. Relevant past medical and surgical history, including a history of prior GI bleeding, abdominal surgery (prior abdominal aorta repair …. aortoenteric fistula) radiation therapy (radiation proctitis), major organ diseases (including cardiopulmonary, hepatic, or renal disease), inflammatory bowel diseases, and recent polypectomy (postpolypectomy bleeding)

The physical examination: assessment of vital signs, cardiac and pulmonary examinations, abdominal and digital rectal examinations. The initial laboratory examination: complete blood cell count, blood typing and cross-matching and measurements of serum electrolytes, blood urea nitrogen, creatinine, and coagulation factors.

The first hematocrit or hemoglobin measurement may not reflect the degree of blood loss, but it will decrease gradually to a stable level over 24 to 48 hours.

Patients older than 60 years of age, those with severe blood loss or continued bleeding (significant decrease in hematocrit or postural changes in blood pressure or pulse rate), and those with significant comorbid illness are at the greatest risk for complications of GI hemorrhage …. ICU admission

Identification of the Bleeding Source In 80% to 90% of cases, acute GI hemorrhage resolves spontaneously without recurrence It is prudent to localize the bleeding source 1.especially in those with significant bleeding or comorbidities 2.direct treatment if does not spontaneously resolve 3.recognition who are at risk for further bleeding.

In patient with acute gastric or duodenal ulcer bleeding, acid suppression with an IV PPI may maximize clot stability and enhance platelet aggregation

PPI in combination with appropriate endoscopic management, decrease the risks for ulcer rebleeding, need for urgent surgery, and death. Direct visualization of the bleeding site by endoscopy can alter patient management.

Classification systems, such as the Forrest Ulcer Description or the Rockall Scoring System, rely heavily on endoscopic criteria for rebleeding risk stratification Various stigmata of hemorrhage may be identified within the ulcer crater.

Stigmata that carry a high risk for rebleeding include Forrest 1A: Active bleeding Forrest 1B: Oozing without visible vessel Forrest 2A: Visible vessele without bleeding Forrest 2B: Adherent clot Forrest 2C: Pigmented spot within the ulcer crater Forrest 3: Clean base ulcer

Patients found to have high-risk stigmata are likely (~50%) to have continued or recurrent bleeding. In such patients, the site of bleeding may be treated by injection therapy with vasoconstrictors or saline, thermal therapy by electrocautery, or mechanical therapy by placement of endoscopic clips(alone or in combination )

These endoscopic therapies decrease rates of rebleeding, mortality, need for transfusion, need for surgery, and length of hospital stay Recently developed alternatives, such as hemostatic sprays and cyanoacrylate compounds

Historical points and objective findings often enable localization of the bleeding site(upper GI tract, the lower GI tract) For the patient with melena or hematemesis, the upper GI tract should be examined first.

Hematochezia more commonly indicative lower GI bleeding, but when the pace of bleeding is brisk …. upper GI tract lesion Placement of a nasogastric tube with aspiration of contents is a reasonable first step.

The absence of blood does not by itself rule out the presence of an upper GI source ….. blood from a duodenal bulb ulcer may not flow back into the stomach to allow sampling by the nasogastric tube In general, in patients with acute GI hemorrhage who have significant blood loss …. upper endoscopy(initial step)

If lower GI tract suspected …. sigmoidoscopy or colonoscopy is choice If lower GI bleeding is so brisk(hemodynamic change) ….. EGD …. colonoscopy ….. scintigraphic erythrocyte scans or technetium-99m(99mTc)-labeled sulfur colloid or pertechnetate can localize the bleeding site if the rate of blood loss exceeds 0.5 mL/minute .

The recent description of capsule endoscopy followed by directed push or balloon enteroscopy has provided a possible endoscopic means of delineating and controlling bleeding lesions in the small bowel There is no role for barium studies in the evaluation of acute GI hemorrhage

CHRONIC GASTROINTESTINAL HEMORRHAGE Chronic GI bleeding is a diagnostic challenge It can manifest as self-limited, recurrent episodes of melena or hematochezia, but usually without the degree of hemodynamic compromise

Some patients have no overt evidence of blood loss but rather have persistent anemia and persistent occult blood loss The evaluation is less urgent, and the likely causes of bleeding differ from those associated with acute GI bleeding.

Patients with this condition usually have undergone upper and lower endoscopy at least once without identification of a bleeding source ….. Small bowel

The small intestine is a difficult area to examine because of its length and configuration In general, the small intestine is initially evaluated radiographically The patient may ingest barium, which is followed through the length of the small intestine ….. enteroclysis ….. Computed tomography and magnetic resonance enterography

Flat mucosal lesions such as vascular ectasias, a common cause of obscure bleeding, may easily be missed If radiographic studies are unrevealing, capsule endoscopy or with push or balloon enteroscopy.

For the patient with persistent blood loss, no endoscopically identified source of bleeding in the upper GI tract or colon, and negative findings on radiologic studies, the entire small intestine may be examined at laparotomy with endoscopy in the operative suite .

In addition, angiographic evaluation of the whole GI tract may reveal the source of chronic blood loss.