Gastrointestinal

Question 1

What is the most common cause of small bowel obstruction?

Answer 1

Intra-abdominal adhesions related to abdominal surgery

Crohn’s Disease

Question 2

What are the most common causes of large bowel obstruction?

Answer 2

Mechanical obstruction - Abdominal or pelvic malignancy, sigmoid volvulus
Functional obstruction - toxic megacolon or pseudo-obstruction (Ogilvie Syndrome)

Question 3

Which measurement in an ABG is mode indicative of ischaemia?

Answer 3

High lactate

Question 4

What does the ‘coffee-bean sign’ represent?

Answer 4

Classical appearance of sigmoid colon volvulus on an abdominal x-ray.

Question 5

Patients with bowel obstruction are usually made NBM - why is this?

Answer 5

To help decompress the bowel (NG tube also inserted).
Also, it is likely that they may need surgery and patients have to starved of food for 6 hours and clear fluid for 2 hours prior to surgery to reduce risk of aspiration during induction of anaesthesia.

Question 6

Why is bowel obstruction a potential complication of Crohn’s Disease?

Answer 6

In CD you can get stricture or abscess formation which causes obstruction. Obstruction is much more common with CD than UC.

Question 7

What is a ‘true colic’?

Answer 7

When there is a baseline of no pain - biliary colic and renal colic are not classed as true colics because you usually still experience mild pain at baseline.

Question 8

Why might flexible sigmoidoscopy be contraindicated in a patient with bowel obstruction?

Answer 8

Risk of perforation

Question 9

What is Ogilvie Syndrome?

Answer 9

Another name for pseudo-obstruction, when a patient presents with very similar features to mechanical bowel obstruction but there is no obstructing lesion in the lumen. It is a functional problem.

Question 10

How does acute appendicitis present?

Answer 10

Central abdominal pain that worsens and radiates to RIF
Feverish
Vomiting

Question 11

What is Rosving’s sign?

Answer 11

Pain in RIF on palpation of LIF, can indicate acute appendicitis.

Question 12

What is Psoas sign?

Answer 12

Pain in RIF on extension of R hip, caused by irritation of psoas major muscle due to inflamed appendix being in a retrocaecal position.

Question 13

Where is McBurney’s Point?

Answer 13

2/3rds of the way between the umbilicus and the ASIS - there is likely to be rebound tenderness and percussion pain over this point in acute appendicitis.

Question 14

What is rebound tenderness?

Answer 14

Pain that occurs on sudden release of pressure on the abdomen.

Question 15

What is the management for acute appendicitis?

Answer 15

Urgent appendicectomy (laparoscopic where possible)
Pre-operative antibiotics if the appendix is perforated
Appendix is usually sent to histopathology to check for malignancy.

Question 16

What does a Hartmann’s procedure involve?

Answer 16

Proctosigmoidectomy with formation of an end colostomy.

Question 17

What is Whipple’s procedure?

Answer 17

Pancreaticoduodenectomy - removal of the head of the pancreas, first part of duodenum, gallbladder and bile duct

Question 18

Name some risk factors for pancreatic cancer.

Answer 18

Diabetes
Smoking
Alcohol

Question 19

What does the term ‘icterus’ mean?

Answer 19

Medical term for jaundice

Question 20

List some common differentials for epigastric pain.

Answer 20

Acute pancreatitis
Peptic ulcer disease
Rule out cardiac events e.g. MI, aortic dissection(can present with epigastric pain)
Gastritis
Boerhaave's perforation

Question 21

What is Boerhaave’s perforation/syndrome?

Answer 21

Distal oesophagus ruptures due to a sudden raised pressure caused by forceful emesis - this is an emergency.
Presents with triad of vomiting, chest pain and subcutaneous emphysema.
Important in a history to establish if epigastric pain started before or after vomiting - if after then consider this differential

Question 22

Name some risk factors for peptic ulcer disease.

Answer 22

H. Pylori
Smoking
Drugs - NSAIDs, steroids
Stress
Reflux (gastric ulcers)

Question 23

What is acute pancreatitis?

Answer 23

Sudden inflammation of the pancreas that causes enzymes (amylase) to be released into the small intestine and hormones (insulin and glucagon) into the bloodstream. Can lead to damage and potential necrosis of the pancreas.

Question 24

Name some complications of acute pancreatitis.

Answer 24

Pancreatic pseudocyst
Necrosis
Abscess/infection
ARDS
Sepsis + death

Question 25

What is the difference between MRCP and ERCP?

Answer 25

MRCP uses a magnetic field and radio waves to evaluate the gallbladder, bile ducts, pancreas and pancreatic duct. ERCP is an endoscopic procedure and is more invasive than MRCP. MRCP is not a therapeutic procedure and is only used for diagnosis, whereas ERCP is used for both diagnosis and treatment.

Question 26

What is malaena and what is the explanation for it?

Answer 26

Black tar-like stools that are usually a result of an upper GI bleed. The blood is partly digested as it passes throughout the GI tract.

Question 27

How does H.pylori lead to ulcer formation?

Answer 27

The gram negative bacterium is present in the stomach of some people. It can weaken the protective mucosal coating in the stomach, allowing acid to get through and damage mucosa, forming an ulcer.

Question 28

What is the eradication regime for helicobacter pylori?

Answer 28

Triple therapy for 7 days of 2 antibiotics and a PPI, usually: Clarithromycin Amoxicillin Omeprazole or lansoprazole

Question 29

How is H.pylori tested for?

Answer 29

Urea breath test Stool antigen test Lab serology (bloods) Any of the above can be used, although urea breath test should not be performed within 2 weeks of treatment with a PPI or within 4 weeks of ABX treatment.

Question 30

How does the urea breath test diagnose H.pylori?

Answer 30

Patients swallow urea that is labelled with an isotope (often radioactive), if isotope-labelled carbon dioxide is detected in exhaled breath then this indicates that H.pylori is present - this is because H.pylori uses the enzyme urease to convert urea to ammonia and carbon dioxide.

Question 31

What shape is H.pylori and what colour would it be on a gram stain?

Answer 31

Spiral-shaped | Gram negative therefore pink/red

Question 32

What colours are gram negative and gram positive bacteria on a gram stain?

Answer 32

Gram positive - distinct purple due to the retention of the violet stain in the thick peptidoglycan layer of the cell wall. Gram negative - pink/red as they are unable to retain the violet stain due to the structure of their cell wall.

Question 33

What is a Mallory-Weiss tear?

Answer 33

Tear of the mucous membrane most commonly at the gastroesophageal junction - may result in bleeding from the GI tract.

Question 34

What is the difference between a Mallory Weiss Tear and Boerhaave's Syndrome?

Answer 34

MWT - not transmural | BS - transmural perforation

Question 35

What is the gold-standard investigation for an upper GI bleed?

Answer 35

OGD

Question 36

What are the 2 types of hiatus hernia?

Answer 36

Sliding -gastro-oesophageal junction slides up into the chest, more likely to cause GORD symptoms. Rolling - gastro-oesophageal junction remains intact but a bulge of stomach herniated up into the chest alongside the oesophagus, less likely to cause GORD symptoms.

Question 37

What is peritonitis?

Answer 37

Acute inflammation in the peritoneal cavity.

Question 38

What are the 2 types of peritonitis?

Answer 38

Primary - usually streptococcal infection (pneumoniae or pyogenes) that spreads from bloodstream. Secondary - perforation of any of the organs in the peritoneal cavity e.g. peptic ulcer, appendicitis, diverticular disease, anastomotic leak etc... Secondary is much more common than primary.

Question 39

What sign on abdominal examination is typically characteristic of peritonitis?

Answer 39

Guarding + rigidity.

Question 40

What is the management for an acute upper GI perforation?

Answer 40

Conservative - IV PPI Surgical - sutured closure of perforation, partial gastro to my if recurrent perforation Triple eradication therapy if H.pylori present

Question 41

What is the screening programme for bowel cancer in the UK?

Answer 41

Testing offered to both men and women between the ages of 60-75 every 2 years. Home test - uses antibodies against human Hb to detect blood in faeces..

Question 42

How do symptoms differ between left and right sided colon cancer?

Answer 42

Left - tumours usually present earlier, more likely to present with change in bowel habit, rectal bleeding and tenesmus. Right - tumours usually present later on, more likely to experience abdominal pain, and anaemia.

Question 43

What is familial adenomatous polyposis?

Answer 43

Autosomal dominant inherited condition that causes numerous polyps to form in the epithelium of the large intestine, polyps are benign but if left untreated can become malignant.

Question 44

What is the gold standard imaging for colorectal carcinoma?

Answer 44

Colonoscopy with biopsy. | CT chest abdo pelvis may be done later on for staging purposes.

Question 45

Which staging system is used for colorectal carcinoma?

Answer 45

TNM staging (Duke’s staging can also be used but is being phased out).

Question 46

Name some differentials for a groin lump.

Answer 46

``` Hernia Groin abscess Saphena varix Femoral aneurysm Inguinal lymphadenopathy Ectopic or undescended testes ```

Question 47

What is a saphena varix?

Answer 47

Dilatation of the saphenous vein at its junction with the femoral vein in the groin, often mistaken for a femoral hernia as it displays a cough impulse.

Question 48

Which imaging investigation would be first line in diagnosing a hernia?

Answer 48

Ultrasound