2 Gastrointestinal Bleeding

Bleeding patterns and possible sources

Gastrointestinal bleeding is blood loss from anywhere in the digestive tract. It may be overt, meaning visible, or occult, meaning hidden and sometimes detected only through anemia or stool testing. Acute bleeding can rapidly become life-threatening, so recognizing deterioration and supporting circulation are immediate priorities.

Causes include peptic ulcers, varices, diverticular disease, and other intestinal conditions. Slow or recurrent bleeding may cause anemia, fatigue, weakness, pallor, or shortness of breath rather than obvious blood in vomit or stool.

Distinguishing upper and lower bleeding

Upper GI bleeding begins in the esophagus, stomach, or duodenum. Possible signs include hematemesis, which is vomiting bright-red blood; coffee-ground emesis, which is altered blood; and melena, or black, tarry stool. Important causes include ulcers and esophageal or gastric varices.

Lower GI bleeding most often presents as hematochezia, meaning bright-red or maroon blood passed rectally. Causes include diverticular bleeding, angioectasia, colitis, and anorectal conditions.

Stool appearance does not always identify the source. A brisk upper GI bleed can cause hematochezia, particularly when the patient is unstable, so blood passed rectally should not be assumed to come from the colon.

Recognizing deterioration and assessing the patient

Treat suspected significant GI bleeding as an emergency. Escalate promptly for syncope or near-syncope, confusion, new restlessness, tachycardia, falling blood pressure, rapid breathing, cool or clammy skin, pallor, reduced urine output, ongoing large-volume bleeding, or chest pain. These findings can signal poor perfusion or hemorrhagic shock. A normal blood pressure alone does not rule out early deterioration.

What to assess and report

• The amount, color, frequency, and timing of blood in vomit or stool; note clots and recurrence.

• Vital-sign trends, mental status, skin perfusion, pain, and urine output.

• Relevant history, including prior GI bleeding, ulcer or liver disease, cardiovascular disease, and recent procedures.

• Medicines that affect bleeding, especially anticoagulants, antiplatelet drugs, and NSAIDs. Record the medication and last dose; medication changes or reversal require clinician-directed decisions.

Initial stabilization and nursing care

Resuscitation and assessment proceed at the same time. Follow local emergency protocols and the clinical team’s orders.

1. Escalate and support ABCs. Call for urgent clinical help for instability or active heavy bleeding. Assess airway and breathing, provide oxygen if indicated or ordered, and use aspiration precautions if the patient is vomiting blood or has reduced alertness.

2. Support circulation. Keep the patient at rest and NPO while urgent evaluation is underway. Establish or assist with large-bore IV access as directed, and prepare ordered fluids and blood products. Obtain blood samples promptly; these commonly include CBC, chemistry, coagulation studies, and blood type and crossmatch. An initially normal hemoglobin does not by itself exclude acute blood loss; interpret results with the clinical picture and trends.

3. Monitor closely. Repeat vital signs and assess perfusion, mental status, visible bleeding, and response to treatment at a frequency appropriate to acuity. Measure and document intake and output. Report declining urine output, recurrent bleeding, or worsening observations immediately. Use continuous cardiac monitoring when indicated by instability or comorbidity.

4. Reassess and communicate. Document stool or emesis characteristics, measured volumes when feasible, interventions, and response. Give concise handoff updates, including trends and medication history. Provide calm explanations and preserve privacy.

Diagnostic procedures and treatment decisions

Prepare for clinician-directed diagnostic and definitive treatment. Assist with ordered endoscopy, imaging, or interventional procedures, and verify preparation and safety instructions.

For hospitalized upper GI bleeding, upper endoscopy is generally performed within 24 hours after initial stabilization. For hemodynamically significant ongoing lower bleeding, CT angiography may help localize the source. Stable patients may undergo colonoscopy after appropriate preparation; it need not routinely occur within 24 hours. For most hospitalized patients with lower GI bleeding, colonoscopy within 24 hours has not improved key outcomes compared with nonurgent inpatient colonoscopy. Timing depends on stability, ongoing bleeding, preparation, and the treating team’s plan.

For hospitalized upper GI bleeding, ACG guidance suggests a red-cell transfusion threshold of hemoglobin $7\ \text{g/dL}$ for most patients. Decisions are individualized, especially with ongoing instability or relevant comorbidities. This is a clinician-directed treatment threshold, not a substitute for bedside assessment or emergency resuscitation.