GI bleeding Flashcards
Top differentials for hematemesis in patient with pneumonia on Abx
ulcer and gastritis
How do you differentiate between melena and iron supplements
melena smells
Occult GI bleeding positive = think …
colon cancer
Top differential in alcoholic with haematemesis
varices secondary to liver disease
Differences in the presentation of oesophageal vs gastric tumour
oesophageal tumour more likely to cause haematemesis at a later stage after dysphagia, whereas gastric tumour will have necrosis in ulcer so first presentation is often haematemesis
Mechanism of stress ulcers
Vagal stimulation due to acid hyper secretion, systemic acidosis causes mucosal injury, splanchnic vasoconstriction - hypoxia due to reduction of blood flow
Mallory weiss tears are common in
alcoholics (often also have oesophagitis) and bulimics
2 causes of peptic ulcer disease
Increased acid: zollinger Ellison syndrome, hyperparathyroidism, chronic renal failure
Reduced mucosal defence: H pylori (most common), NSAIDs, cigarettes, corticosteroids
How does H pylori weaken mucosal defence
Mucous is rich is carbs, H pylori digests carbs and exposes mucosa to action of acid
Functions of paracetamol
1 = redue temperature
2= painkiller
How does codeine cause constipation
Inhibits peristalsis of bowels, contents become more dehydrated, vicious cycle
Pain killers for colic
Buscopan > paracetamol/NSAIDs
Mechanism behind gastroesophageal varices
Resistance to portal blood flow, angiogenic factors and increased nitrous oxide production in splanchnic vascular bed, splanchnic arteriolar vasodilation and increased portal outflow
Varices temporary fix
balloon can be used to compress
Uncommon causes of haematemesis
Dieulafoy’s lesion- dilated aberrant submucosal vessel that erodes overlying epithelium not associated with ulcer (endoscopy reveals active arterial pumping from a site)
◦ Watermelon stomach or gastric antral vascular ectasia
◦ Aorta-enteric fistula (often infected prosthetic aortic graft eroding into intestine), some present with back/abdo pain, others with fever associated with sepsis
Benign lesions of oesophagus or stomach
Lipomas, polyps, blue rubber bleb Nevus syndrome
What type of cancer is most common in oesophagus
adenocarcinoma more than Squamous cell carcinoma (look at barrets oesophagus)
Points to remember when diagnosing GI bleed
where is blood loss, colour/smell/consistency, amount, history of PUD, signs of chronic liver disease, recent negation of NSAIDs/aspirin/warfarin, history of retching
Diverticulitis vs cancer
Cancer more common cause of bleeding in over 50, diverticulitis could present with abdominal pain too
Fissure and piles gender distribution
Piles more common in men, fissures more common in women
What is always indicated with PR bleeding
DRE/PR
Rectal cancer order of symptoms usually
pain and then bleeding
Angiodysplasia leads to bleeding in presence of
constipation or blood thinners
When to think about inflammatory/ischaemic colitis or UC
Abdo pain, raised inflammatory markers, haematochezia
Bleeding in ischaemic colitis
Jelly, dark, mucous-like bleeding
Why is it important not to miss ischaemic colitis
necrosis and perforation requiring surgery can occur
Features of colonic diverticula
often psychiatric patients due to reduced bowel motility from medications, painless/painful haematochezia,
herniation of colonic mucosa and submucosa through the muscular layers of the colon, colonic tissue is pushed by the intra-luminal pressure,
common location is left colon (most common cause of benign lower GI bleed in adults) (more common in women due to constipation and distension, in men the more common cause of haematochezia is perforation)
Colonoscopy is often indicated in
haematochezia from haemorrhoids just to rule out cancer and check piles is actual cause
Which type of haemorrhoids is more common
Internal
Classic presentation of colon cancer
recent change in bowel habits, can have palpable mass on abdo/PR exam, painless occult bleed is most common manifestation, iron deficiency anaemia
features of colon cancer genetics
- Colon cancer has a strong genetic component, can present young, more common in young men, young patients often have a very aggressive cancer leading to worse outcomes
What is IBD
inappropriate immune response to endogenous commensal microbiota within the intestines, intestinal epithelial dysfunction with or without some component of autoimmunity
major UC symptoms
diarrhoea, rectal bleeding, tenesmus, crampy abdo pain, look for extra intestinal manifestations
Ischaemic colitis is associated with
atherosclerosis/vasculitis, segmental due to collateral circulation
Points to remember in blood PR
amount of bleed and colour of blood, blood on toilet paper, blood coated in stool pattern, diarrhoea and mucus PR, FH of colorectal cancer, Age (children - Meckel’s diverticulum)
Is admission warranted in melena
- Admission warranted in malaena due to suspicion of internal bleed- give colonoscopy if OGD unremarkable
What divides upper and lower GI
ligament of treitz
Treatment of upper GI bleed
- Treatment of GI bleed: clinical assessment, blood test, aggressive resuscitation, diagnostic tests (endoscopy/radiology), transfusion
- Must keep perfusion of vital organs, assess bp and urine output/kidney function to assess success of fluid resuscitation
Appearance and source of PR bleeding
