Appendicitis

Question 1

What is your impression and goals of management?

A 10 year old boy presents with a 2-day history of fever and acute abdominal pain which later localises to RIF.

Answer 1

Impression → Acute appendicitis. I am concerned about the potential for perforation and intraperitoneal sepsis and/or abscess formation and I would perform a rapid bedside assessment using the paediatric assessment triangle and proceed to a complete a-e assessment as appropriate, particularly if there are signs of shock or sepsis. I would like help from a paeds reg or the paediatric surgery team on call, with a view for urgent surgical intervention.

Goals

1. Ensure the patient is haemodynamically stable
2. Take a targeted history/examination to assess the pain and proceed with further investigations as appropriate
3. Management with supportive and definitive treatment, likely including a laparoscopic appendicectomy
4. Prevention of short term and long term complications (gangrene, perforation, abscess, paralytic ileus and adhesions)

Differentials

• GIT → IBD, Meckel’s diverticulitis, mesenteric adenitis, gastroenteritis, tumour (neuroblastoma, Wilms’), bowel obstruction, volvulus, intussusception
• Non-GIT → testicular torsion, abdominal trauma, DKA, EBV

Question 2

Appendicitis: history

Answer 2

History

• Classic pattern → periumbilical pain that migrates and is localised over McBurney’s point in the RIF. May differ depending on anatomical position of appendix.
• Associated symptoms → low grade fever, anorexia, nausea, vomiting, diarrhoea, generalised malaise
• Screen for peritonism → car ride painful? Does it hurt to cough?
• Targeted history to rule out differentials → IBD (blood in stool, change in bowel habit, extra-articular manifestations), intussusception (abrupt onset of episodic intermittent abdo pain, vomiting, blood in stool), lower lobe pneumonia (resp symptoms), DKA (vague abdominal pain), S/LBO (vomiting, distension, constipation, pain)
• Past medical history including developmental and family history → recent viral infection (mesenteric adenitis, lymphoid hyperplasia as cause of appendicitis), low fibre diet/constipation, surgical history, vaccinations, comorbidities, allergies (AMPLE for surgery)

Question 3

Appendicitis: examination

Answer 3

Examination

• Vitals and fluid status → fever, hypotension & tachycardia (sepsis)
• Abdominal examination
  
  • McBurney’s point tenderness (maximum tenderness ⅓ of the distance from R ASIS to umbilicus)
  • Peritonitis → rebound tenderness, percussion tenderness, guarding, Dunphy’s sign (pain on coughing), Rovsing’s sign (RLQ pain on LLQ palpation)
  • Psoas sign → RLQ pain with passive right hip extension (retrocecal appendix lies against psoas major m.)
  • Obturator sign → RLQ pain on internal rotation of flexed right hip (pelvic appendix lies against obturator internus m.)
  • Mass → peri-appendiceal abscess (perforation that contained by the omentum)
• Respiratory examination → rule out LL pneumonia

Question 4

Appendicitis: investigations

Answer 4

Appendicitis is a presumptive clinical diagnosis, with clinical tools such as the Alvarado score combining clinical criteria to rule out appendicitis with a sensitivity of 96% (migratory RLQ pain, anorexia, nausea/vomiting, RLQ tenderness, rebound tenderness, fever and leukocytosis).

• Bedside → BGL (DKA), UA (UTI, DKA), blood cultures
• Bloods → FBC, CRP, EUC, consider LFT, coags and group & hold
• Imaging
  
  • Abdominal ultrasound → non-compressible appendix dilated >6mm with increased wall thickening (>3mm), pain on probe application, periappendicular fluid accumulation, sonographic McBurney sign
  • Consider CT abdo with IV contrast (if U/S inconclusive), erect CXR/AXR (pneumoperitoneum, bowel obstruction)

Question 5

Appendicitis: management

Answer 5

Supportive

• IV fluid resuscitation
• Analgesia
• Keep patient NBM

Specific

• Antibiotic therapy – pending surgery
• Gentamicin + metronidazole + amoxicillin/ampicillin
  
  • Uncomplicated → if acute non-perforated appendicitis, stop after surgery
  • Complicated → if acute perforated appendicitis – swap antibiotics based on sensitivities from surgery, total therapy duration is 5 days (IV + oral - step down once able). If sensitivites not back after 72 hours stop gentamicin and change to amoxicillin+clavulanate
• Surgery – laparoscopic appendicectomy

Disposition

• OT + recovery in surgical ward
• Discharge home once afebrile, tolerating regular diet, pain-free or well controlled on simple analgesia