Abdomen - diaphragm + abdominal structures

Abdomen - diaphragm + abdominal structures

1. wall

   • inguinal hernia - due to inguinal canal weakness
     • direct
       • medial to the inferior epigastric artery
       • intestine passes through superficial ring only
     • indirect
       • intestine protrudes at deep inguinal ring and passes through superifical inguinal ring
       • lateral to inferior epigastric artery
   • femoral hernia
     • occurs below inguinal canal
       • due to femoral canal weakness

2. peritoneum

   • retroperitoneum
     • covers organs - mnemic = sad pucker
       • s - suprarenal (adrenal glands)
       • a - aorta
       • d - duodenum except cap
       • p - pancreas
       • u - ureters
       • colon - except transverse
       • k - kidneys
       • e - esophagus
       • r - rectum
   • intrperitoneum
     • around organs
       • stomach
       • liver
       • spleen
   • folds
     • mesentry - connects organs to abdominal wall
     • omentum - extends from stomach to other organs
       • greater - from greater curvature of stomach to transverse colon
       • lesser - from lesser curvature of stomach to liver

3. diaphragm

   • muscles involved in forced inspiration
     • accessory muscles
       • scalenes
       • sternocleidomastoid
       • pectoralis major + minor
     • serratus anterior
     • latissimus dorsi
   • muscles involved in forced expiration
     • abdominal muscles
     • intercostal muscles
       • internal
       • innermost
   • works with intercostal muscles but does most of work
   • left crus
     • right crus

4. liver

   • if blood flow through portal system is obstructed by liver cirrhosis = pressure increases = portal hypertension

5. bowel

   • function
     • digestion
     • absorption
     • excretion

6. oesophagus

   • anatomy
     • upper 3rd skeletal, lower 3rd muscle, in middle mix
     • inner circular + outer longitudinal
     • squamous epithelium
   • innervation
     • innervated by vagus nerve
     • controlled by upper oesophageal sphincter called cricopharynx
       • lower oesophageal sphincter stops stomach contents travelling backwards
     • myentric plexus - controls motility
     • aurbechs plexus - peristaltic movements
     • submucosal plexus
     • meisners plexus
     • intrinsic afferents
       • submucosal AH neurones
       • myentric AH neurones
       • myentric s neurones

7. stomach (gastrum)

   • part of innate immunity
   • controls rate of food entering duodenum by pyloric sphincter
   • acid secretion/microbacterial infection
   • 3 muscle layers
     • longitudinal
     • oblique
     • circular
   • rugae (folding of wall)
   • columnar epithelium
   • gastric pits

8. pancreas + duodenum

   • hepatic duct from liver drain valve
     • when not eating = stored in cystic duct
     • when eating hepatic juices through common valve and to duodenum
       • gallstones from gallbladder to duodenum = x gallblader drainage
         • an get pancreatitis as pancreatic duct cannot drain
   • foregut + midgut supplied by celiac + superior mesentreric arteries
   • peyers patches (lymphoid aggregated in ileal mucosa) can go inside out when young = intussuscpetion
   • layers of GI wall -

9. small intestine

   • from jejunum to ileum diameter, thickness, + no. of folds increase
   • illeovaecal phincter - seperates small + large intestine
   • mesentry
   • intestinal villi
     • lacteal - cisterna chyli
       • originates from cisterna chylii in the abdomen - goes through diaphragm and into neck
         • drains bowel
           • fats absorbed from bowel goes up cisterna chylii - if damaged have to stop eating fatty things
     • venule portal system

10. colon

    • ileum to anal canal
    • re-absorbs water + electrolytes
    • eliminates waste
    • no villi
    • some mesentry
    • mucosa has crypts for mucus secretion

Images and files in the map