MET3 Revision - Gastroenterology II COPY Flashcards
Which anatomical point distinguishes between an upper and lower GI bleeding? [1]
Ligament of Treitz:
- Proximal: upper GI
- Distal: lower GI
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
What is a mallory weiss tear? [1]
Describe typical presentation [1]
Forceful vomiting / retching causing a mucosal tear in the oesophagus causing subsequent bleeding
First bout of vomiting has no bleeding (prior to tear)
Second + bout of vomiting has bleeding
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
When taking a history for upper GI bleed, what should you investigate? [3]
History:
- Determine if upper or lower GI bleed: haematemesis?
Systemic symptoms of blood loss?
- Dizzyness
- Palpitations
- Chest pain
Risk factors?
- Drugs
- Chronic liver disease (portal HTN?); IHD (anticoagulants); CKD (poorer prognosis)
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.
What is this endoscopic tx for oesophageal variceal bleeding? [1]
Explain how it works [2]
Sengstaken-Blakemore Tube [1]
Tube into stomach; inflate balloon; pull up agaisnt fundus of stomach; compresses varices so that blood can’t flow into varices}
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.
Describe the presentation of diverticulosis [3]
Diverticulosis may cause lower left abdominal pain that relieved by defecation, constipation or rectal bleeding
Describe the presentation of the complications of significant peptic ulcerations [4]
Haematemesis (vomiting blood)
Coffee ground vomiting
Melaena (black, tarry stools)
Fall in haemoglobin on a full blood count
Describe the treatment pathway for the initial resuscitation of perforated peptic ulcer disease [4]
IV fluids
Nasogastric tube insertion:
- reduces amount of gastric fluids in GIT AND allows nill by mouth
IV PPI
- loading and maintence doses
- enhance sealing of perforation
Antibiotics:
- stop sepsis due to leaking of fluids into peritoneum
Use one of the following methods to achieve haemostatic control of an actively bleeding ulcer via endoscopy:
A mechanical method (e.g., clips) with adrenaline (epinephrine)
Thermal coagulation with adrenaline
Fibrin or thrombin with adrenaline.
Describe what is meant by Zollinger-Ellison syndrome [1]
It is made from a triad of which three causes? [3]
Zollinger-Ellison syndrome (ZES) is a condition caused by a gastrin-secreting tumour that causes hypersecretion of gastric acid leading to ulcer disease.
Triad:
1) gastric acid hypersecretion, sustained by:
2) fasting serum hypergastrinemia causing:
3) peptic ulcer disease and diarrhea
