Medicine Library

Gastroenterology

Upper and lower gastrointestinal bleeding

Written 30 September 2026. This date is not a physician-review date.

Why this matters

The color of the blood matters less than whether the patient is shocked.

Rapid clinical summary

  • Resuscitate before you negotiate an elective endoscopy.
  • Hematemesis and melaena are upper until proved otherwise. Fresh red blood per rectum can still be a brisk upper bleed.
  • A transfusion target is protocol-specific. It is not printed here.

Mechanism

Blood leaves the gut faster than it can be replaced. Portal hypertension, ulcer, and mucosal disease are different sources with different definitive treatments, but shock looks the same at the door.

Recognition

Shock plus gastrointestinal blood is a resuscitation problem first.

Typical

  • Hematemesis
  • Melaena
  • Hematochezia
  • A liver history
  • Antiplatelet or anticoagulant drugs

Red flags

  • Hypotension
  • Tachycardia
  • Confusion
  • Ongoing hematemesis
  • A suspected variceal source

Differential

ConditionClueTrap
Peptic ulcerPain, an anti-inflammatory drugAssuming every bleed is variceal
VaricesKnown cirrhosis, signs of chronic liver diseaseA routine outpatient endoscopy
Diverticular lower bleedLarge-volume fresh blood, older adult, hemodynamics may still failForgetting that brisk upper bleeding can look the same

Investigations

  • Hemoglobin lags behind acute loss. Do not wait for anemia to believe a shocked patient.
  • Endoscopy after resuscitation, with the timing set by stability and the likely source.

Management

Immediate
Airway if vomiting blood and consciousness is falling. Two points of access, blood bank, and reversal of anticoagulation according to the local protocol.
Definitive
Endoscopic, radiological, or surgical hemostasis depending on the source. Variceal and ulcer pathways are not the same. Drugs are not dosed on this page.
Monitoring
Pulse, blood pressure, and whether bleeding is continuing. A single ‘stable’ set of observations during a pause is not a cure.

Common pitfalls

  • Sending ongoing hematemesis to a clinic.
  • Using the hemoglobin alone to judge acute loss.
  • One protocol for varices and ulcers.

Exam reasoning

The next step in a hypotensive patient is resuscitation, not a booking.

Practice this topic

Opens original Mahazanaka questions in this subject. If this subject is thin on that track, the session uses what exists.

Visual summary

Blood, then the camera

Endoscopy follows resuscitation.

Blood, then the cameraBleedingShock?ResuscitateThen endoscopy

Recognize, reason, prioritize, act safely

  1. Recognize. Blood from the gut, and the vital signs.
  2. Reason. Upper or lower, variceal or not, still bleeding or not.
  3. Prioritize. Airway and circulation before the camera.
  4. Act safely. Resuscitate, then the hemostatic procedure.

Knowledge check

  • Ongoing hematemesis and blood pressure 80/50. What comes before a routine endoscopy slot?

No citation is attached to this chapter. Nothing here is personal medical advice.