Caecum and the appendix Flashcards
What is the caecum
Blind intestinal pouch between the ileum and the ascending colon
Function of the caecum
Stores chyme
Length of the caecum
7.5cm
Location of the caecum
In the right iliac fossa
Inferior to the ileoceacal junction
2.5cm away from the inguinal ligament
When is the caecum palpable
If distended due to faeces, gas or malignancy
Where is the caecum covered with peritoneum
Entirely covered
Does the caecum have mesentery
No
What binds the caecum to the lateral abdominal wall
Cecal folds of peritoneum
What is the appendix
Blind intestinal diverticulum that contains lymphoid tissue
Where is the appendix attached
To the posteromedial end of the caecum inferior to the ileoceacal junction
What are the most common positions of the appendix
Retrocecal (behind the caecum) Sub ileal (parallel with terminal ileum)
Shape of the mesoappendix
Short
Triangular
What is the mesoappendix derived from
Posterior side of the mesentery of the terminal ileum
Arterial supply of the caecum
Abdominal aorta -> SMA -> ileocolic artery -> Anterior and posterior cecal arteries
Arterial supply of the appendix
Abdominal aorta -> SMA -> ileocolic -> appendicular
Venous drainage of the caecum
Ileocolic vein which drains into the SMV
Venous drainage of the appendix
Appendicular vein which drains into the ileocolic vein
Innervation of the caecum and appendix
Ileocolic branch of the superior mesenteric plexus
What does lymph from the caecum and appendix drain into
Upper and lower ileocolic lymph nodes via intermediate mesenteric nodes (many intermediate nodes from caecum, 1 intermediate node from appendix)
Where are the ileocolic lymph nodes
Surrounding the ileocolic artery
What is appendicitis
Acute inflammation of the appendix
Common cause of appendicitis in young people
Increase in lymphoid tissue size which occludes the lumen
Common cause of appendicitis in 30+ people
Blockage in the appendix with faecal matter
Why does the appendix increase in size in appendicitis
It cannot drain
How does the pain in appendicitis change
Stretching if the visceral peritoneum causes vague pain in the umbilical region
As the appendix swells it irritates the parietal peritoneum causing severe pain in the right lower quadrant
Treatment for appendicitis
Appendectomy
What can appendicitis lead to if not removed
Peritonitis as the appendix becomes necrotic and ruptures
