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
What is Omentum ?
(1.) Double layered extension of peritoneum containing vessels + lymphs + nerves
(2. ) Greater Omentum
- From greater curvature of stomach and proximal duodenum to posterior abdominal wall
- This can fold on itself to form 4 layers
(3. ) Lesser Omentum
- From lesser curvature + proximal duodenum to liver
What is the epiploic foramen
(1. ) Opening to lesser sac from greater sac
(2. ) Hepatic duodenal ligament runs along the free edge of the lesser omentum. This contains the portal triad
What is a peritoneal dialysis?
(1. ) Used in pt with renal failure
(2. ) Peritoneum is semi-permeable to small molecules
(3. ) Sterile dialysis soln introduced into cavity
(4. ) Soln absorbs waste products from blood
(5. ) This is then drained out the cavity
Where are the lowest places in the body when in a supine + upright position?
Bacteria and tumours gravitate to these areas
1. ) Behind the right lobe of liver (supine
(2. ) Pelvic cavity (upright)
Describe the structure of the stomach
(1. ) It is a J shaped intraperitoneal organ found in LUQ
(2. ) It contains rugae (mucosa folds) that inc SA
(3. ) Comprises of: cardia, fundus, body, antrum, pylorus
(4. ) Inferior-oesophageal sphincter is not under voluntary control
(5. ) Pyloric sphincter = controls exit of chyme (food + gastric acid)
Describe the structure of the duodenum
(1. ) 1st part = smooth wall, intraperitoneal
(2. ) 2nd, 3rd, 4th part = plicae circularis, retroperitoneal
(3. ) Papillae is found halfway the 2nd part, this allows for the opening of pancreatic secretion + bile from ampulla of Vatar
How may a peptic ulcer cause brisk bleeding?
(1. ) Gastroduodenal artery is found behind the 1st part duodenum
(2. ) Peptic ulcer will erode the duodenum mucosa + erode the GDA -> brisk bleeding
(3. ) Causes = chronic NSAID therapy, h.pylori infection
Describe the nerve supply (PNS and SNS), blood supply and venous drainage of the stomach
Nerve Supply
(1. ) CNX (PNS)
(2. ) T5-9 (SNS)
Blood Supply
(1. ) Short gastric + R + L gastric a. = lesser curvature
(2. ) R + L gastricepiploic a = greater curvature
Venous drainage
(3. ) R + L gastric vein - drains into HPV
(4. ) Short gastric v., L+R gastricepiploic v. drains into SMV
What branches come off the coeliac trunk
(1. ) Common hepatic A
- gives rise to R.Gastric A. + GDA (which gives rise to R.gastroepiploic a.)
- Hepatic artery proper is a continuation of the artery
(2.) L.Gastric A.
(3. ) Splenic A.
- gives rise to short gastric a. + L.gastroepiploic A
Where would you palpate the liver
(1. ) R.hypochondrium + epigastrium area
(2. ) L.lobe is above the costal margin so can’t be palpated
(3. ) R.lobe may be palpated on inspiration
Describe the microscopic structure of the liver + portal triad
(1. ) Hepatocytes arrange in lobules
(2. ) Drained by a central hepatic vein
(3. ) Portal triad found on the periphery
(4. ) Porta hepatitis comprises of: HPV, Hepatic A, Bile duct, lymphatic vessels, CNX parasymp fibres
Describe the blood supply to the liver + where does it get its oxygen from ?
(1. ) Hepatic artery proper
- comes from common hepatic artery of CT
- branches into left and right hepatic A, cystic a comes of the r. hepatic a.
- supplies 25% of liver’s oxygen via arterial blood
(2. ) HPV
- Liver receives most of its blood from HPV.
- This is poorly oxygenated venous blood from the bowel that need to be detoxified but still carries 75% of livers oxygen supply
(3. ) Hepatic vein
- venous blood from hepatocytes drained in to IVC
What is hepatic encephalopathy?
Normal:
- Liver reconfigures proteins (absorbed into the blood in bowel) + ensures they are safe
Liver Disease
- Above process fails
- Short AA chains are toxic and may bypass liver through porto-systemic shunt
- Toxic protein enters brains -> neurological disease
Describe the surface of the liver
Surface
(1. ) Diaphragmatic, concave smooth surface = anterior and superior aspects
(2. ) Visceral surface = posterior-inferior surface
Lobes
(1. ) Porta hepatis separates the CAUDATE and QUADRATE (inferior) lobes. Neurovascular structures enter and leave here except for HV
(2. ) RIGHT and LEFT lobes separated by falciform ligament
Bare area
(1. ) Under central tendon of diaphragm
(2. ) Within anterior and posterior folds of the coronary ligament
Describe the ligaments of the liver
(1. ) Coronary ligament
- comprises of anterior and posterior folds
- attaches superior surface of liver to inferior surface of diaphragm
(2. ) Triangular ligaments
- continuation of coronary ligaments
(3. ) Falciform ligament
- Divides R+L lobes
- Attaches liver to abdominal wall
- Free border has ligament teres
(4. ) Ligament venosum
- Remnant of the ductus venosum
(5. ) Ligament teres
- Remnants of umbilical vein
- makes up inferior aspect of falciform ligament
What cause hepatomegaly
(1. ) Cirrhosis
(2. ) Congestive heart failure
(3. ) Viral infection (hepatitis)
These impedes blood flow
What is a porto-systemic shunt?
(1. ) It is where the portal system (HPV) anastomoses/communicates with the systemic venous system
(2. ) An example is where the oesophagus vein drains into the azygous vein (systemic system) instead of left gastric vein (portal system). This bypasses the liver
(3. ) Liver bypass means detoxification can’t take place and this will enter the circulation and may enter the brain -> disease
(4. ) Cirrhosis can cause portosystemic shunts and oesophageal varices formation
Describe the PNS and SNS to all of the gut structures
PNS
(1. ) Foregut + Midgut = CNX
(2. ) Hindgut = S2,3,4
SNS
(1. ) Foregut = T5-9
(2. ) Midgut = T10-T11
(3. ) Hindgut = T12
why may you get small bowel obstruction?
(1. ) Jejunum and ileum are in mesentery (attached to posterior abdo wall)
(2. ) This allows them to be very mobil so can become volvulus and involved in hernias
How do the the jejunum and ileum allow for nutrient absorption?
They have high SA due to the following:
(1. ) Long length
(2. ) Plicae circularis (mucosal folds)
(3. ) Villi on mucosal folds
(4. ) Microvilli on epithelial cells
List 4 differences between the jejunum and ileum
Jejunum
- Left upper quadrant
- Plicae circularis is more pronounced
- Longer vasa recta
- Less arcades
Ileum
- Lower right quadrant
- Shorter vasa recta
- More arcades
- Payer patch
Describe three features of the large intestines
The large bowel starts in the r.iliac fossa at the ileo-caecal valve.
(1. ) Haustrations = circular inner layer bulges
(2. ) Epiploic appendages = fat filled pouches of peritoneum that hang from the tenia coli
(3. ) Tenai coli = longitudinal muscular strips that run from appendix to rectum -> there is only 3 of these
List 5 difference between the small and large intestines
(1. ) Location
- SI = central
- LI = edges
(2. ) External Structure
- SI = smooth, muscular, cylinder tube
- LI = variable diameter, haustrations, tenai coli
(3. ) Mesentery
- SI = neat + tidy mesentery
- LI = epiploic appendages, t.mesocolon, s.mesocolon
(4. ) Blood supply
- SI = SMA, very high blood supply via vasa rectas
- LI = SMA + IMA, low blood supply
(5. ) Internal structures
- SI = villi, payers patch in ileum, plicae circularis
Describe the biliary tree
(1. ) Liver synthesis and secretes bile
(2. ) This drains into the left and right hepatic ducts that merge into the common hepatic duct.
(3. ) GB stores bile and excretes it (i.e. contract in response to fatty food) into the cystic duct
(4. ) The duct joins the common hepatic duct to form the common bile duct.
(5. ) Common bile duct joins with the pancreatic duct to form the ampulla of vatar
(6. ) Secretion is controlled by the sphincter of oddi and contractions of the papilla muscle - this empties into the 2nd part of the duodenum.
Where is the gallbladder in the abdomen
(1. ) Right hypochondrium region within the midclavicular line at the 9th costal cartilage.
(2. ) It is close to the inferior surface of the liver
Describe where pain may be felt in inflammation of gallbladder (cholecystitis)?
Pain is felt in the epigastrium region (T5-9) and may spread to the shoulder (phrenic nerve) if rubbing under diaphragm. It may also localise to RUQ (dermatome)
pancreas - Surrounding organs/vessels? pancreas function?
- posterior to stomach and SMA (behind uncinate process)
- tail is in contact with spleen’s hilum
- head sits within the ‘C’ of the duodenum
- HPV and abdominal aorta lies behind [head] neck and uncinate process
It is a retroperitoneal organ except for the tail
It is a glandular organ with exocrine and endocrine functions
Blood supply and venous drainage of pancreas
(1. ) Splenic a, pancreatic-duodenal a., SMA
(2. ) HPV
What would you seen in a blockage of the following:
- Sphincter of Oddi
- Pancreatic Duct
(1. ) SoO = Stones may be too large to pas and causes a build up of pigment in blood -> jaundice + liver failure
(2. ) P.Duct = build of pancreatic juice digestive enzymes + high pressure causes it to leak out -> digestion of pancreas (acute pancreatitis)
Where is the spleen and can it be palpated? Function?
(1. ) It is an intraperitoneal organ found in the upper left quadrant
(2. ) It is under the diaphragm and ribcage so can’t be palpated
(3. ) H/e if enlarged it can be palpated at the edge of the left costal margin -> superior border moves inferiormedially and its notches can be palpated
(4.) Function is to filter blood and remove old RBC. It plays a role in both cell mediated + humoral response
Structures that surround the spleen
(1. ) Anterior = stomach
(2. ) Posterior = diaphragm, ribs 9-11
(3. ) Inferior = left colic/splenic flexure
(4. ) Medial = Left kidney, tail of pancreas
why may a splenectomy be performed and will this effect life expectancy?
- Splenectomy may be performed due to ruptured spleen (due to trauma), haematological condition, proliferative disorders
- Liver and bone marrow can take over spleen function h/e pt is at increase infection risk so require life-long Abx.
Describe what you’d find in the 9 regions of the abdomen
(1. ) Epigastric region = some of the pancreas, liver, spleen, stomach
(2. ) Right hypochondriac region = liver, gallbladder and right kidney.
(3. ) Left hypochondriac region = spleen, splenic flexure of the colon, left kidney.
(4. ) Umbilical region = small intestine.
(5. ) Suprapubic region = urinary bladder, sigmoid colon, uterus.
(6.) R and L.Flank
R = A.Colon, right kidney, small intestines
L = D.Colon, left kidney, small intestines
(7.) R and L.Iliac fossa
R = Appendix, caecum, a.colon
L = D.Colon, sigmoid
What is the mediaN and mediaL umbilical ligament?
(1. ) MEDIAN umbilical ligament
- remnant of allantois/urachus
- allantoic duct connected to fetus bladder to umbilical
(2. ) MEDIAL umbilical ligament
- Two of these
- remnant of umbilical a.
- deoxygenated blood from fetus to placenta
