Appendicitis

Question 1

Clinical anatomy
- The appendix is an outpouching of the ________
- Is it intraperitoneal? If so, what is its peritoneum called?
- Does it contain immune tissue?
- Can the position of the appendix be variable? What is its usual location?

Answer 1

Caecum
Intraperitoneal - the mesoappendix
Yes - contains lymphoid follicles
Yes - usually retrocecal

Question 2

Aetiology
- What is the precipitating event for appendicitis?

Answer 2

The lumen of the appendix is obstructed.

May be obstructed by
- Stool: normal or hardened (faecolith)
- Lymphoid hyperplasia: max size during adolescence, can grow in response to viral infection

Question 3

Pathophysiology
- Next steps in appendicitis? (Not complications)

Answer 3

Resident flora of the appendix (E. coli, bacteroides fragilis) get trapped and multiply

Causes an inflammatory response
- WBCs recruited (neutrophils –> pus)
- Fever

Appendix continues to secrete mucus as normal –> increased pressure within the obstructed appendix
- Visceral pain at the umbilical region, N&V, anorexia

Appendix lumen pressure > venous pressure
- Engorgement of vessels –> oedema

Question 4

Pathophysiology
- Why is there migratory pain during appendicitis?

Answer 4

Initially, visceral pain (umbilical region)
Eventually, peritonitic involvement/pain (RIF/McBurney’s point)

Question 5

Complications of appendicitis

Answer 5

• Eventually, appendix can become ischemic/infarcted
• Infarcted appendix can perforate –> gangrenous necrosis
• Inflammation can leak into peritoneal cavity –> peritonitis
• Abscess or phlegmon can form

Question 6

Complications of appendicitis
- Similarities between phlegmon and abscess?
- Differences?

Answer 6

Similarities: both involve neutral infiltration/pus
Difference: abscess has a boundary, phlegmon does not

Question 7

Risk factors for appendicitis?

Answer 7

• Age: 10-30
• Smoking (weak)

Question 8

History
- Murphy’s triad?

Answer 8

RIF pain
N&V
Fever

Question 9

History: all symptoms?

Answer 9

• Migratory abdominal pain
• N&V
• Fever
• Diarrhoea and constipation
• Anorexia

Question 10

Exam
- Vital signs?
- Abdomen?

Answer 10

Vital signs: may indicate shock/sepsis
Abdomen
- Tenderness
- Guarding, rigidity, rebound tenderness
- Cross tenderness (Rosving’s sign)

Question 11

Exam
- Leg signs?

Answer 11

• Psoas sign + obturator sign
• Occur as inflamed appendix comes into contact with these muscles

Question 12

Investigation
- Bedside tests?

Answer 12

Urinalysis: rule out UTI

Question 13

Investigation
- Lab investigations?

Answer 13

• FBC: leukocytosis with left shift (ie. High neutrophil count)
• UEC: potentially raised lactate due to infarction, N&V may cause deranged renal function in severe cases
• CRP: predicts severity of inflammation
  Group and save: in case blood transfusion is needed

Question 14

Investigations: imaging
- First line?
- Second line?

Answer 14

First line: abdominal ultrasound
Second line: contrast enhanced CT abdomen, abdominal MRI

Question 15

Investigations: imaging
- Positive finding on abdominal ultrasound?

Answer 15

> 6mm

Question 16

Investigations: imaging
- Why would a CT be used over ultrasound?
- Why would an MRI be used over ultrasound and CT?

Answer 16

CT: if ultrasound is inconclusive, suspecting complications
MRI: as above, PLUS if pregnant

Question 17

Investigations: imaging
- What findings would be found in CT abdo or MRI?

Answer 17

Diameter >6mm
Calcified appendicolith
Periappendiceal inflammation (eg. fat stranding)

Question 18

Alvarado score (MANTRELS)
- What does it stand for?
- Results?

Answer 18

Question 19

Management
- Initial management?

Answer 19

If in shock: fluid resuscitation
Analgesics: paracetamol or opiod
Prophylactic antibiotics: ceftriaxone and metronidazole
Nil by mouth if surgery is indicated

Question 20

Management: uncomplicated appendicitis
- Surgery indicated?
- Are post op IV antibiotics indicated?
- Alternative?

Answer 20

Question 21

Management of complicated appendicitis?

Answer 21

• Surgery indicated?
• Are post op IV antibiotics indicated?
• Alternative?

Question 22

Patient explanation
- What is the appendix?
- What is appendicitis?
- Importance of treating appendicitis ASAP?

Answer 22

Appendix is an outpouching of your bowel.
Appendix gets blocked, bacteria within it multiply, leading to the appendix becoming infected and inflammed.
Important for appendicitis to be treated ASAP. May burst, causing a serious infection called peritonitis.