Acute presentations and emergencies
Upper GI bleeding
Overview and approach
Upper GI bleeding presents with haematemesis or melaena; brisk upper bleeding can cause haematochezia.
- Causes: peptic ulcer, varices/portal hypertensive gastropathy, erosive oesophagitis/gastritis, Mallory-Weiss tear, malignancy, Dieulafoy lesion, angiodysplasia.
- Separate variceal from non-variceal bleeding early: management differs1,2.
- How common each cause is: peptic ulcer is the leading cause (up to about half, increasingly NSAID-related). Varices range from about 5% to 40% depending on the population. Mallory-Weiss tears are about 5-10%. Erosive gastropathy and oesophagitis usually cause only minor bleeding4.
- Who dies: overall mortality is about 5-10%, but few die from blood loss itself; most die from decompensation of other illnesses. Under 60 without major comorbidity, mortality is under 1%. Older age, comorbidity and tachycardia or hypotension predict rebleeding and death4.
- Mallory-Weiss tear: usually on the gastric side of the junction after retching or vomiting; 80-90% stop on their own and few rebleed4.
- Rarer causes worth naming: Dieulafoy lesion (a large aberrant artery bleeding through a pinpoint mucosal defect), gastric antral vascular ectasia (watermelon stomach), hereditary haemorrhagic telangiectasia, aorto-enteric fistula after aortic graft surgery, and bleeding from the bile or pancreatic duct4.
- Stress ulceration occurs only in the critically ill: major trauma, surgery, burns over a third of the body, severe brain injury, ventilation or coagulopathy4.
Assessment and clinical features
ABCDE, haemodynamic trends, perfusion, comorbidities and antithrombotics; assess liver disease/varices and resuscitate while investigating.
- History: NSAIDs, aspirin, anticoagulants, alcohol, liver disease, prior ulcer, vomiting before haematemesis (Mallory-Weiss), weight loss.
- Signs: tachycardia, hypotension, postural drop, pallor, stigmata of chronic liver disease, melaena on PR.
- Reading the stool: melaena means blood has been in the gut for at least about 14 hours, so the more proximal the source, the more likely melaena is. Fresh red or maroon blood from an upper source means very brisk bleeding and usually comes with instability and a falling haemoglobin4.
Differentials and investigations
FBC, electrolytes, renal function, coagulation and group/crossmatch; urgent senior review and endoscopy planning. Risk tools supplement clinical assessment.
- Urea disproportionately raised suggests upper source. Lactate and ECG in unstable or elderly patients.
- Why urea rises: blood proteins digested and absorbed in the small bowel, plus reduced renal perfusion from volume loss4.
- Haemoglobin lags: it can be near normal at first and falls over up to 72 hours as fluid moves into the circulation. Slow chronic bleeding can give a very low haemoglobin with normal vital signs, plus a low MCV and high RDW from iron deficiency4.
- A clear nasogastric aspirate does not exclude upper bleeding: it occurs in up to 18%, usually from a duodenal source4.
- What the ulcer looks like at endoscopy predicts rebleeding4.
| Ulcer finding | Rebleeding risk | Implication |
|---|---|---|
| Active bleeding or visible vessel | High (about a third without endoscopic treatment) | Endoscopic haemostasis and admission |
| Adherent clot | Intermediate | Admission; endoscopic therapy considered |
| Flat pigmented spot | Low | No endoscopic therapy needed |
| Clean base | Close to zero | Early discharge if stable and otherwise well |
- Most rebleeding happens within the first 3 days4. Risk scores (for example Glasgow-Blatchford) can identify low-risk patients; use the local tool and threshold.
Management and follow-up
IV access, targeted fluid/blood resuscitation and gastroenterology involvement; suspected variceal bleeding needs its specific vasoactive/antibiotic pathway. Reversal decisions require senior input.
- Non-variceal (ACG 2021): endoscopy within 24 hours of presentation; restrictive transfusion threshold haemoglobin 7 g/dL (8 g/dL with cardiovascular disease); erythromycin may be used before endoscopy; after successful haemostasis of an ulcer, high-dose PPI for 3 days then twice-daily PPI to 2 weeks1,3.
- Suspected variceal (Baveno VII): immediate vasoactive drug (terlipressin, somatostatin or octreotide) for 2-5 days, antibiotic prophylaxis from admission, endoscopy within 12 hours after resuscitation2.
- Anticoagulant reversal and restart: senior and haematology advice.
- Preventing recurrence: about a third of bleeding ulcers rebleed within 1-2 years if nothing is changed. Prevention targets the three drivers: H. pylori (eradication cuts rebleeding to under 5%), NSAIDs and acid4.
Red flags and clinical pearls
Shock, ongoing haematemesis or impaired airway protection demands immediate escalation. An initially normal haemoglobin does not exclude major acute blood loss.
- Early airway protection if large haematemesis or reduced consciousness.
References
- ACG Clinical Guideline: Upper Gastrointestinal and Ulcer Bleeding (2021)
- Baveno VII: Renewing consensus in portal hypertension (PMC)
- Gastroenterology Advisor: 2021 ACG guideline summary
- Longo DL, Fauci AS, Kasper DL, Hauser SL, Jameson JL, Loscalzo J, editors. Harrison's Principles of Internal Medicine. 18th ed. New York: McGraw-Hill; 2012. Chapter 41, Gastrointestinal bleeding.
Last updated from Sen’s notes on 22 October 2026.