Acute Appendicitis Flashcards
In which patients is the diagnosis of acute appendicitis difficult
- patients less than three
- pregnant
- older than 60
At which age does appendicitis usually occur
Occurs most frequently in the second and third decades of life
What is the incidence of appendicitis in the 10 to 20 year age group
233/ 100 000
Where is the vermiform appendix located
-Near the ileocaecal valve where the taenia coli converge on the caecum
What is the blood supply of the appendix
It is supplied by the appendicular artery, terminal branch of the ileocolic artery, which is a branch of the superior mesenteric artery
The attachment of the appendix to the base of the caecum is constant, however where may the tip migrate to?
It may migrate to the retrocaecal, subcecal, preileal, post ileal and pelvic positions
What has been proposed as the primary cause of appendicitis?
- Obstruction of the lumen (Frequently implicated but not always required)
- Appendiceal obstruction may be caused by faecoliths, calculi, lymphoid hyperplasia, infectious processes and beneign or malignant tumours
What is the natural history of appendicitis following obstruction
- Obstruction leads to increased luminal and intramural pressure resulting in thrombosis and occlusion of the small vessels in the appendiceal wall and stasis of lymphatic flow
- As the appendix becomes engorged, the visceral afferent nerve fibres at T8-10 are stimulated
- Significant inflammation –> necrosis –> perforation –> localized abcess formation or diffuse peritonitis
What are the classic symptoms of acute appendicitis
- Right lower quadrant (iliac fossa) abdominal pain
- Anorexia
- Nausea and vomiting
- Abdominal pain is the first symptom; it is peri umbilical in nature with subsequent migration to the right lower quadrant as the inflammation progresses
- Fever and leucocytosis follow later in the cause of the illness
- High grade fever may be a sign of a perforated appendix
Differential diagnosis of acute appendicitis
- Urinary tract infection
- Renal calculi
- Gastroenteritis
- Ruptured ovarian cyst
- Pelvic inflammatory disease
- Cholecystitis
- Diverticulitis
- Small bowel obstruction
Signs of acute appendicitis
- Localized tenderness
- Rebound tenderness
- Guarding
- Generalized peritonitis (perforation)
What is Rovsing’s sign
-Palpation of the left lower quadrant eliciting pain in the right lower quadrant
What is obturator sign
Pain with internal rotation of the hip (Pelvic appendix)
What is iliopsoas sign
Extension of the right hip eliciting pain in the right hip (retrocaecal appendix)
What lab investigations should be done if acute appendicitis is suspected
- Full blood count
- Urinalysis
- Pregnancy test
