GI: Acute Appendicitis

Question 1

What is appendicitis? How is it caused?

Answer 1

Inflammation of the appendix, usually initiated by obstruction of the lumen causing invasion and infection of appendix wall by gut flora.

Obstruction usually secondary to a FAECOLITH, but may involve LYMPHOID HYPERPLASIA. IMPACTED STOOL and rarely, APPENDICEAL or CAECAL TUMOUR.

Question 2

What is the lifetime risk of appendicitis?

Answer 2

7-8%

Question 3

Describe the possible positions of the appendix.

Answer 3

• retrocaecal (12 o’clock): 65%
• pelvic (4 o’clock): 30%
• paracolic (11 o’clock): 2%
• midinguinal (6 o’clock): 2%
• pre-ileal (2 o’clock): 1%
• post-ileal (2 o’clock(: 0.4%

Question 4

Describe the common symptoms of acute appendicitis.

Answer 4

• abdominal pain: initially peri-umilical (dull and poorly localised) then migrates to RIF (sharp and well localised), aggravated by movement and coughing
• nausea and vomiting
• anorexia
• diarrhoea or constipation

Question 5

In which patient groups do classical symptoms often not appear?

Answer 5

• young children
• elderly
• pregnant women

Question 6

What signs might be present in a pt with appendicitis?

Answer 6

• tachycardia
• pyrexia
• rebound tenderness
• percussion pain over McBurney’s point
• guarding (if perforated)
• rovsing’s sign: RIF pain on palpation of LIF

Question 7

What sign may be elicited in a pt with a retrocaecal appendix?

Answer 7

PSOAS SIGN: RIF pain on extension of right hip due to inflamed appendix abutting psoas major

Question 8

What sign may be elicited in a pt with a pelvic appendix?

Answer 8

OBTURATOR SIGN: pain with internal rotation of hip due to inflamed appendix abutting obturator

Question 9

Which investigations would you perform in a Pt with suspected appendicitis?

Answer 9

1. Bedside tests
   - urinalysis: exclude UTI
   - pregnancy test: exclude ectopic pregnancy
2. Bloods
   - FBC: usually mild increase WCC
   - CRP: usually increased
3. Imaging
   - USS abdo: may help if unclear diagnosis or in assessment of appendix mass or abscess
   - CT abdo: more sensitive and specific than USS for acute appendicitis
   - diagnostic laparoscopy - may be consideredd

Question 10

Which signs would suggest appendicitis on a CT scan?

Answer 10

• appendix enlargement
• appendiceal wall thickening and enhancement
• peri-appendiceal fat stranding

Question 11

How would you manage a Pt with appendicitis?

Answer 11

1. ABCDE
2. IV fluids
3. analgesia - opiates
4. laparoscopic appendicectomy (or open if complicated) - send appendix to histopathology to look for malignancy
   +/- antibiotic therapy

Question 12

Suggest possible complications of appendicitis.

Answer 12

1. perforation and peritonitis
2. surgical site infection
3. appendix mass: omentum and small bowel adhere to appendix. Usually presents with a fever and palpable mass. Initial treatment usually conservative with fluids, analgesia and antibiotics but urgent surgical intervention may be required if the mass enlarges or the patient’s condition deteriorates.
4. appendix abscess: can be shown by USS or CT. Initial treatment is usually by percutaneous or open drainage (open drainage also enables appendicectomy).