IM15.1-18 | GI Bleeding — Glossary

Life-threatening ABO-incompatible transfusion complication causing intravascular haemolysis; presents with fever, rigors, back pain, haemoglobinuria, hypotension, and DIC; management: immediately stop transfusion, saline IV, repeat crossmatch and Coombs test, maintain urine output, renal support if AKI.

A linear tear in the anoderm, usually posterior midline; presents with severe perianal pain during and after defecation, and bright red blood on the toilet paper; diagnosis by perianal inspection.

Acquired arteriovenous malformations of the colon, typically in elderly patients (>60 years); associated with aortic stenosis and chronic renal failure (Heyde's syndrome); presents with recurrent painless lower GI bleeding.

An abnormal communication between the aorta (or aortic graft) and the GI tract, most commonly the third portion of the duodenum; presents as the herald bleed (small sentinel haemorrhage preceding massive UGIB) and is a surgical emergency.

Second-line H. pylori eradication for clarithromycin-resistant or triple-therapy-failure cases: bismuth subcitrate + tetracycline + metronidazole + PPI for 10–14 days; eradication rates approximately 85–90%.

A hard palpable mass in the pouch of Douglas felt on digital rectal examination; indicates peritoneal carcinomatosis, most often from gastric, ovarian, or colonic primary tumours — sometimes called 'rectal shelf.'

The ratio of blood urea nitrogen to serum creatinine; a value >20:1 (or BUN/creatinine >30 in mg/dL) in the absence of pre-existing renal disease suggests an upper GI source of bleeding due to protein digestion and absorption raising BUN.

Wireless swallowed capsule camera that captures images of the small bowel mucosa over 8–10 hours; first-line investigation for obscure GI bleeding (negative OGD and colonoscopy); identifies source in ~50–60% of obscure bleeds.

IV ceftriaxone 1 g/day for 7 days is the standard antibiotic prophylaxis for cirrhotic patients with variceal haemorrhage; reduces spontaneous bacterial peritonitis, bacteraemia, and bacterial infections that trigger rebleeding; Level 1A evidence for reducing mortality — not optional.

A clinical scoring system for cirrhosis severity using bilirubin, albumin, INR/prothrombin time, ascites (clinical), and encephalopathy grade; scores 5–6 = Class A (compensated), 7–9 = Class B (significant dysfunction), 10–15 = Class C (decompensated, highest mortality); used to estimate 30-day mortality in variceal bleeding.

A rapid urease test performed on antral mucosal biopsy at endoscopy to detect H. pylori infection; produces a colour change if urease is present; susceptible to false-negatives with PPI, bismuth, or antibiotic use within 2 weeks of testing.

A multi-phase CT scan of the abdomen and pelvis with contrast that can detect active GI bleeding at rates as low as 0.3–0.5 mL/min; provides anatomical localisation and identifies the feeding vessel prior to therapeutic angiography; the primary advanced investigation when endoscopy fails.

Omeprazole and esomeprazole inhibit CYP2C19, which is required to bioactivate clopidogrel to its active antiplatelet metabolite; this interaction reduces clopidogrel efficacy and may increase cardiovascular event risk; pantoprazole and rabeprazole have minimal CYP2C19 inhibition and are preferred in clopidogrel-treated patients.

A congenitally enlarged submucosal artery in the stomach that erodes into the lumen without overlying ulceration, causing recurrent painless massive haematemesis; difficult to identify endoscopically.

Examination of the anal canal and rectum by insertion of a lubricated gloved finger; assesses sphincter tone, rectal wall (for masses, mucosal irregularity), prostate (in males), and stool character; essential in all patients with lower GI bleeding or unexplained iron-deficiency anaemia.

Acute painless haematochezia from erosion of an arteriole at the neck of a colonic diverticulum; the most common cause of significant acute LGIB in adults over 50; ceases spontaneously in ~80% of cases.

Herniation of the colonic mucosa through the muscle wall, most common in the sigmoid colon; diverticular bleeding is the most common cause of significant acute lower GI bleeding in adults over 50 — painless, abrupt, large-volume, ceasing spontaneously in ~80% of cases.

Endoscopic placement of elastic bands around oesophageal varices at OGD, causing ischaemic necrosis and fibrosis; first-line endoscopic treatment for oesophageal variceal bleeding; more effective and with fewer complications than endoscopic sclerotherapy.

Dilated vascular cushions below the dentate line; visible externally as soft vascular masses; classic positions at 3, 7, and 11 o'clock; present with bright-red blood coating the stool or on the toilet paper, typically with straining.

An immunochemical test for haemoglobin in stool, specific for human haemoglobin and not affected by diet; used for screening of colorectal carcinoma and investigation of unexplained iron-deficiency anaemia; superior specificity compared to guaiac-based occult blood tests.

An endoscopic classification of peptic ulcer stigmata of recent haemorrhage: Ia (spurting artery, ~55% rebleed), Ib (oozing), IIa (visible non-bleeding vessel, ~43%), IIb (adherent clot, ~22%), IIc (flat pigmented spot, ~10%), III (clean base, <5%); guides decision for endoscopic haemostasis.

A blood product containing all coagulation factors; indicated in GI bleeding when INR exceeds 1.5 or in massive transfusion protocols to correct dilutional coagulopathy.

A pre-endoscopy clinical risk score for upper GI bleeding that incorporates BUN, haemoglobin, systolic BP, pulse, presence of melaena/syncope, hepatic disease, and cardiac failure; used to identify patients who can be safely discharged without endoscopy (score 0 = very low risk) and to predict need for clinical intervention.

Standard first-line H. pylori eradication regimen: PPI twice daily + clarithromycin 500 mg BD + amoxicillin 1 g BD (or metronidazole 400 mg BD if penicillin-allergic) for 14 days; eradicates H. pylori in approximately 75–85% of cases; confirm eradication with urea breath test or stool antigen test at ≥4 weeks post-therapy.

Vomiting of blood, either fresh bright-red or 'coffee-ground' (partially digested by gastric acid); indicates an upper GI source proximal to the ligament of Treitz.

Passage of fresh red or maroon blood per rectum; typically indicates a lower GI source, but can occur in massive rapid upper GI bleeding.

A state of circulatory failure and tissue hypoperfusion caused by loss of intravascular blood volume; classified into four phases based on estimated blood volume loss and physiological decompensation.

Intravenous proton pump inhibitor (e.g. omeprazole or pantoprazole 80 mg bolus, then 8 mg/hour for 72 hours) given after endoscopic haemostasis for peptic ulcer bleeding; maintains gastric pH >6 to optimise haemostatic clot formation and platelet aggregation; reduces rebleeding and mortality.

Chronic relapsing inflammatory disease of the GI tract; ulcerative colitis (UC) affects the colon/rectum with bloody diarrhoea and mucus; Crohn's disease can affect any segment with transmural inflammation; both present with systemic features (fever, weight loss, arthralgia).

The self-amplifying combination of hypothermia, metabolic acidosis, and coagulopathy seen in severe haemorrhagic shock; each component worsens the others, making haemorrhage increasingly refractory to treatment.

The suspensory ligament of the duodenojejunal flexure, anatomically marking the boundary between the upper and lower GI tract; used to classify GI bleeding sources.

Haemorrhage originating from the jejunum, ileum, colon, rectum, or anus, distal to the ligament of Treitz; typically presents as haematochezia (fresh red blood per rectum).

A longitudinal mucosal laceration at the gastro-oesophageal junction resulting from forceful vomiting or retching; commonly associated with alcohol use; usually self-limiting.

Black, tarry, foul-smelling stool resulting from digestion of blood by intestinal bacteria during transit; indicates haemorrhage proximal to or from the right colon; ~50–100 mL blood required.

Model for End-Stage Liver Disease; calculates 3-month mortality using creatinine, bilirubin, and INR; MELD ≥18 in variceal bleeding identifies patients benefiting from early pre-emptive TIPS; used alongside Child-Pugh for transplant prioritisation.

Bleeding of unknown origin after negative upper GI endoscopy and colonoscopy; typically originates from the small bowel; investigated with capsule endoscopy as first-line, then deep enteroscopy (balloon-assisted) for therapeutic access.

A synthetic somatostatin analogue; inhibits release of vasodilatory gut peptides (glucagon, VIP), causing indirect splanchnic vasoconstriction and reduced portal pressure; dose: 50 mcg IV bolus then 50 mcg/hour infusion for 3–5 days; fewer cardiovascular side effects than terlipressin; preferred alternative when terlipressin is contraindicated (ischaemic heart disease).

Dilated tortuous submucosal veins in the lower oesophagus forming as portosystemic collaterals when portal pressure exceeds 12 mmHg; rupture causes torrential haematemesis with high mortality.

Ulceration of the gastric or duodenal mucosa caused principally by H. pylori infection and/or NSAID use; the most common cause of UGIB worldwide.

A resuscitation strategy in uncontrolled haemorrhage that targets a MAP of 50–65 mmHg (below normal) to avoid diluting coagulation factors and worsening bleeding until definitive haemostasis is achieved; particularly relevant in trauma and in variceal bleeding.

Elevation of portal venous pressure above 5–12 mmHg, typically due to cirrhosis; when portal pressure exceeds 12 mmHg, oesophageal and gastric varices form and risk haemorrhage.

A fall in systolic blood pressure of ≥20 mmHg (or diastolic ≥10 mmHg) on moving from lying to standing, accompanied by a rise in pulse of ≥20 bpm; in the context of GI bleeding, indicates significant intravascular volume deficit (typically ≥1 litre).

IV erythromycin 250 mg administered 30–90 minutes before OGD for UGIB to stimulate gastric motility (prokinetic effect via motilin receptors) and clear blood/clot from the stomach, improving mucosal visualisation and diagnostic yield.

Non-selective beta-blocker that reduces portal pressure by reducing cardiac output (beta-1 blockade) and causing splanchnic vasoconstriction (beta-2 blockade — unopposed alpha vasoconstriction); given after an acute variceal bleed episode as secondary prophylaxis to reduce re-bleeding risk; combined with repeat endoscopic band ligation until variceal eradication.

A class of drugs that irreversibly inhibit the H⁺/K⁺-ATPase proton pump on parietal cells; most potent acid suppressants available; IV high-dose infusion (80 mg bolus then 8 mg/hour for 72 hours) is standard post-endoscopic therapy for peptic ulcer bleeding (Forrest Ia/Ib/IIa/IIb); maintains gastric pH >6 to support haemostatic clot.

Evidence-based strategy of transfusing packed red cells only when Hb falls below 7 g/dL (or 8 g/dL in cardiovascular disease) in haemodynamically stable patients; shown in the Villanueva 2013 NEJM trial to reduce 45-day mortality, rebleeding rates, and length of stay compared with liberal strategy (Hb <9 g/dL).

The evidence-based strategy of transfusing packed red cells only when haemoglobin falls below 7 g/dL (or 8 g/dL in cardiovascular disease) in haemodynamically stable patients; associated with lower mortality and rebleeding than liberal strategies.

A combined pre- and post-endoscopy risk score for UGIB predicting mortality and rebleeding; requires endoscopic findings (diagnosis, stigmata of recent haemorrhage) for full calculation; used after endoscopy to stratify ongoing risk, not to decide whether to perform endoscopy (that is the Blatchford's role).

Clinical signs that indicate established liver disease and portal hypertension, including spider naevi, palmar erythema, leukonychia, gynecomastia, ascites, splenomegaly, caput medusae, and jaundice; their presence in a patient with GI bleeding strongly suggests variceal haemorrhage and mandates vasoactive therapy.

A non-invasive immunoassay detecting H. pylori antigen in stool; valid in the acute setting (unlike the urea breath test); useful for diagnosing active H. pylori infection when CLO test is negative due to PPI use, and for confirming eradication after treatment.

Nuclear medicine scintigraphy that detects active GI bleeding at rates as low as 0.1–0.4 mL/min over a 24-hour window; most sensitive for intermittent or slow bleeding; localises to a general region (not the specific vessel); used as a first step before angiography when active bleeding is uncertain.

A synthetic long-acting analogue of vasopressin activated in vivo to lysine-8-vasopressin; causes splanchnic vasoconstriction via V1 receptors, reducing portal pressure; given IV 2 mg Q4h for 48 hours then 1 mg Q4h for 3–5 days total; first-line vasoactive therapy for variceal bleeding with Level 1A mortality evidence; contraindicated in ischaemic heart disease.

An interventional radiology procedure creating an intrahepatic shunt between portal and hepatic veins to decompress portal hypertension; salvage therapy for variceal bleeding refractory to two endoscopic treatments; achieves haemostasis in ~90–95%; major complication: hepatic encephalopathy (from portosystemic shunting of nitrogen-containing compounds).

Selective catheterisation and embolisation of the bleeding vessel in the mesenteric circulation using coils, foam, or gel to achieve haemostasis; requires active bleeding ≥0.5–1 mL/min on angiography; used when endoscopic haemostasis fails.

Severe pulmonary oedema occurring within 6 hours of transfusion, not explained by circulatory overload; caused by donor antibodies activating recipient neutrophils; presents as acute respiratory distress with bilateral infiltrates on chest X-ray; managed with respiratory support.

A radiological procedure that creates an intrahepatic shunt between the portal and hepatic veins to decompress portal hypertension; used as salvage therapy for variceal bleeding refractory to two endoscopic and pharmacological interventions; achieves haemostasis in ~90–95% but may precipitate hepatic encephalopathy.

Haemorrhage originating from the oesophagus, stomach, or duodenum, proximal to the ligament of Treitz; typically presents as haematemesis and/or melaena.

Haemorrhage from portosystemic collateral varices (most commonly oesophageal) due to portal hypertension; managed with vasoactive drugs (terlipressin or octreotide), prophylactic antibiotics (ceftriaxone), and endoscopic band ligation.

The original portal-hypotensive vasoconstrictor; largely replaced by terlipressin due to high rates of cardiovascular side effects (myocardial ischaemia, hypertension); if used, must be combined with IV nitroglycerin to mitigate systemic vasoconstriction.