MET3 Revision - Gastroenterology II Flashcards
State the causes of upper GI bleeds [5]
Peptic Ulcer Disease – 44%
Oesophagitis - 28%
Gastritis/Erosions – 26%
Erosive Duodenitis – 15%
Varices – 13%
Portal Hypertensive gastropathy – 7&
Malignancy - 5%
Mallory Weiss Tear – 5%
Vascular Malformation – 3%
State the causes of lower GI bleeds [5]
Diverticular disease (30%)
* Haemorrhoids (14%)
* Mesenteric Ischaemia (12%)
* Colitis (9%)
* Cancer (6%)
* Rectal ulcers (6%)
* Angiodysplasia (3%)
* Radiation (3%)
* Drugs
* Other
What is this cause of upper GI bleeding? [1]
Gastritis
What is the most common cause of portal HTN worldwide? [1]
Schistomiasis
Describe pathophysiology is diverticular disease causing lower GI bleeding? [1]
How does diverticular disease lead to lower GI bleeding? [1]
Diverticular disease:
- a condition where small pouches (called diverticula) form in the lining of your bowel and push out through your bowel wall due to high intra-luminal pressure
-
Diverticulae lie adjacent to mesenteric blood flow and because they cause decreased thickness of colonic thickness; increases chance of bleeding
What are causes of diverticular disease? [6]
- Constipation
- Genetics
- Obesity
- NSAIDs
- Low fibre diet
- Muscle spasm
State 5 causes of haemorrhoids [5]
- Straining (in bowel movement)
- Sitting for long periods
- Chronic diarrhoea or constipation
- Overweight / obese
- Pregnancy
Describe how colonic cancer develops [3]
- polyps;
- larger polyp (severe dysplasia)
- adenocarcinoma
State 4 reasons that cause colitis which in turn causes lower GI bleeding [4]
Ishcaemic colitis: in distal transverse colon / descending colons - position as watershed area between SMA & IMA can lead to bleeding
IBD
Infection
NSAIDs
What are the different classes of blood loss? (% and volume lost?) [4]
Class 1:
- 10-15%
- 750mls
Class 2:
- 15-30%
- 1.5L
Class 3:
- 30-40%
- 2L
Class 4:
- >40%
- 3L
Describe the symptoms that classify each class of shock with regards to blood loss? [4]
Class 1:
- no clinical signs
Class 2:
- postural hypotension
- generalised vasoconstriction
Class 3:
- Hypotension
- Tachycardia over 120
- Tachyopnea
Class 4:
- Marked hypotension
- Marked tachycardia
- marked tachyopnea
- Comatose
Which cannulae are wide bore? [4]
- 14G (300ml/min)
- 16G (150 ml/min)
- 17G
- 18G (75ml/min)
What are possible complications of massive blood transfusion [5]
- Fluid overload
- Electrolyte / Acid-Base disturbance
- Transfusing products devoid of clotting factors (consider giving additional platelets)
- Hypothermia (blood transfused is cold)
Repeated transfusions:
- Iron overload
Which blood tests would you suggest for investigating upper GI bleed? [7]
- Blood gas: contains Hb and lactate levels
- FBC: Hb and clotting levels
- U&E: kidney function
- LFTs
- Coagulation screen
- Cross match (to find a compatible samples for transfusion)
OR - Group and save (instruct transfusion lab to find blood group of patient and save serum of sample sent for later cross match
How do you optimise clotting:
- What levels should: platelets [1] and INR [1] be above/below? [2]
- Drug management? [2]
Platelets: > 50
INR: < 1.5
Do not give any anti-coagulants the Ptx may be on (warfarin, clopidogrel, aspirin, DOAC)
Reverse warfarin with vitamin K
What drugs might be prescribed if have an upper GI bleed? [2]
PPI:
- Decrease lesions identified at endoscopy level; but no difference in transfusion, surgery or mortality
- NICE does not rec. PPI before endoscopy
Tranexamic acid?
- improves clotting in area of GI bleeding, but may improve clotting with poor vascular blood flow & cause CAD.
Specific treatment for variceal bleeding? [2]
Terlipressin:
- causes mesenteric and splachnic vasoconstriction
- contraindicated in IHD
Antibiotics:
- cephalosporin; quinolone; augmentin
- reduces liklihood of sepsis, which decreases portal pressure
- treat chest infection if aspiratio has occurred.
NOTE: Propanolol is prophylaxis
Name the scoring system used to determine if risk of re-bleeding [1]
Which scores result in outpatient endoscopy [1]
Blatchford score
< 2: low risk - outpatient endoscopy
> 6: endoscopic Rx
Name another score (other than Blatchford score) for upper GI blleds [1]
What is important to note about this score [1]
Rockall score: needs endoscopic diagnosis to calculate full score
Describe management of high risk, actively bleeding ulcer [4]
Adrenaline:
- vasoconstriction
- causes local tamponade of blood vessels
Clip: closes bleeding
Diathermy: (therapeutic treatment that uses electric currents (radio and sound waves) to generate heat in layers of your skin below the surface)
Haemospray: powder in endoscope; promotes clotting}}
Describe the endoscopic management of varices [3]
Band ligation
Injection sclerotherapy (glue)
Sengestaken blakemore tube: compresses varices
Explain post-endoscopical / medical therapy for ulcers: [3]
PPIs:
- allow ulcers to heal
- increase gastric pH; improves clotting ability (low pH activates pepsin which inactivates platelets)
- some patients will need continous infusion for 72hrs
H. pylori eradication (triple therapy: 1xPPI; 2xantibiotics)
Reassess of OGD
Describe post-endoscopic treatment of varices [4]
- Beta blockers (reduce portal pressure: carvedilol; propanolol)
- Sequential banding procedures (close future varices)
- TIPPS: blood from portal vein goes straight from liver into systemic system (reduces pressure)
- Liver transplant
When would you use interventional radiology or red cell scanning with GI bleeds? [2]
Describe the procedures [2]
If endoscopy fails / too unwell to have endoscopy
Interventional radiology:
- CT angiogram: IDs bleeding vessel
- Angiography: embolise the vessel
Surgery:
- If have uncontrolled bleeding
- Failed 2x endoscopic treatment
What is the most common cause of small bowel bleeding? [1]
Angiodysplasia: abnormal, tortuous, dilated small blood vessel in the mucosal and submucosal layers of the GI tract.