Abdomen Flashcards
GI, inguinal canal
Blood supply to each gut
(1. ) Foregut = coeliac trunk
(2. ) midgut (distal 1/2 duodenum to 2/3 T.colon) = superior mesenteric artery
(3. ) hindgut (1/3 t.colon to rectum) = inferior mesenteric artery
Sympathetic nerve supply to each gut structure and where would pain be referred to?
(1. ) Foregut = greater splanchic nerve (T5-9) referred to epigastrium
(2. ) Midgut = lesser splanchic nerve (T10-11) referred to umbilical
(3. ) Hindgut = least splanchic nerve (T12) referred to suprapubic
Venous drainage of each gut
(1. ) All gut structures ultimately drain into the hepatic portal vein (HPV)
(2. ) Midgut via superior mesenteric v –> HPV
(3. ) Hindgut via inferior mesenteric v –> splenic vein –> HPV
Name 5 parts of the gut that are retroperitoneal?
(1. ) Pancreas
(2. ) Ascending colon
(3. ) Descending colon
(4. ) 2nd part of duodenum
(5. ) 1st part of rectum
Where is start and end of midgut?
(1.) 1/2 of duodenum to 2/3 of transverse colon
Where is McBurney’s point
- McBurney’s point located on the right side of the abdomen
- One-third of the distance from the anterior superior iliac spine to the umbilicus.
- Base of appendics is found here
Name of hernia that is lateral to inferior epigastric artery
Indirect hernia
What is a direct inguinal hernia
- This is acquired (e.g. heavy lifting) and due to weakening of abdo muscles
- Content (viscera, bowel) herniate through posterior wall of inguinal canal.
- This is medial to the inferior epigastric a.
- Protrusion/peritoneal bulge may be palpated over deep ring
What are the 9 regions of the abdomen and how is it formed?
Horizontal planes:
(1. ) Subcostal plane = lowest part of the costal margin
(2. ) Intertubucular plane = between iliac tubercle (most lateral aspects of iliac crest)
Vertical plane
(3.) Mid-clavicular to mid-inguinal
Regions:
- R and L.hypochondrium (1, 3)
- Epigastrium (2)
- R and L.Flank (4, 6)
- Umbilical (5)
- R and L.Iliac fossa (7, 9)
- Suprapubic (8)
What is the rectus abdominis? How does this form the 6-pack?
(1. ) Runs vertically from the pubis up to the costal margin
(2. ) Tendons cross its length (x3)
(3. ) During exercise the muscle hypertrophies whereas the tendon stays the same - this forms the 3 bulges on either side of the midline
What forms the rectus sheath?
It is formed by the aponeurosis of three flat muscles surrounding the rectus abdominis, the arrangement of layers differ above and below the arcuate line.
Upper 2/3 i.e. above arcuate
(1. ) IOA lies in front and behind the RA
(2. ) EOA lies in front of RA
(3. ) TA lies behind the RA
Lower 1/3 i.e. below the arcuate
(1. ) All three lie infront of the RA
(2. ) TF is in direct contact with RA
What muscles make up the abdominal anterior wall? Describe their fibres and action
(1. ) EO
- ‘hands in pockets’ fibres
- rotation of torso
(2. ) IO
- ‘hands on boobs’ fibres
- compress abdomen, rotation of torso
(3. ) TA
- runs horizontally
- compress abdomen
(4. ) RA
- Compress abdomen
- depress ribs
- stabilise pelvis during walking
What is an indirect hernia
(1. ) Failure of vaginalis to regress
(2. ) Content enters via the deep ring
(3. ) Lateral to the inferior epigastric a
What makes up the boundaries of the inguinal canal? (anterior, posterior, roof, floor, rings)
(1. ) Deep ring = TF
(2. ) Superficial ring = EOA
(3. ) Anterior wall = EOA
(4. ) Floor = EOA (curves under)
(5. ) Roof = IO + TA
(6. ) Posterior wall = Conjoint tendon (IO + TA)
What is content found in the inguinal canal? And what passes behind the canal?
(1. ) Spermatic cord (male)
(2. ) Round ligament (female)
(3. ) Ilioinguinal N.
(4. ) Genitofemoral N.
Femoral vessels are found under the canal: NAVy fronts
- Nerve
- Artery
- Vein
Where is the femoral pulse palpated?
- Between pubic symphysis + anterior iliac spine
- This is the mid-inguinal point (NOT the same as mid inguinal ligament point)
Where is the deep ring of the inguinal canal palpated?
- At the mid inguinal ligament point
- This is the midpoint between the pubic tubercle and anterior iliac spine
What makes up the peritoneal cavity?
(1. ) The peritoneum is a serous membrane made up of visceral and parietal layers.
- visceral = lines organs + forms the mesentery
- parietal = abdominal wall
(2.) The peritoneal cavity is a potential space between the visceral and parietal peritoneum
(3. ) Potential space comprises of greater sac, lesser sac + peritoneal fluid.
- greater sac = spans from the diaphragm all the way to pelvic cavity. This is the main and larger part of the peritoneal cavity
- lesser sac = lies posterior to stomach, anterior to pancreas, inferior to liver
- peritoneal fluid = inc volume will lead to ascites and distended abdomen
What is mesentery? What types are there?
Double layer of peritoneum that contains lymphatics, vessels, adipose tissues. Allows organs to move freely.
Types
(1. ) Proper Mesentery
- Attaches to posterior abdo wall from dueodenal-jejunal flexure to ileo-caecal junction
- allows for bowel to be mobile
- can become twisted (volvulus)
- involved in hernia
(2. ) Transverse mesocolon
- T.colon + posterior abdo wall
(3. ) Sigmoid mesocolon
- sigmoid + pelvic cavity
(4. ) Mesoappendix
- appendix + ileum
What is meant by retro-peritoneal? List organs that are retroperitoneal
- They are outside the peritoneal cavity
- SO only the anterior surface has got parietal peritoneum
- They are fixed in position
Retroperitoneal Organs (SAD PUCKER) - Suprarenal, aorta + IVC, duodenum 2nd part, pancreas, ureters, colon ascending + descending, kidneys, esophagus, rectum first 1/3
What is meant by intraperitoneal? List organs that are intraperitoneal
- Covered in visceral peritoneum
- Organs are mobile in mesentery
- If organs are inflammed, pain can be felt on movement + breathing
- Stomach, spleen, 1st part duodenum, jejenum, ileum, caecum, appendix, t.colon, sigmoid
What parts of the bowels are intraperitoneal?
(1. ) 1st part of duodenum
(2. ) Jejunum
(3. ) Ileum
(4. ) Appendix
(5. ) T.Colon
(6. ) S.Colon