Wu Notes Flashcards
Name structures of the ‘tube’ and their function
Pharynx: mechanical digestion + amylase digestion
Esophagus: has amylase, but mostly just an avenue to get from mouth
Stomach: Digestion with pH+mechanical
Small intestine: absorption, but also has digestive enzymes from pancreas
Large intestine: absorption!
Function of pancreas, gallbladder, and liver
Pancreas: makes digestive enzymes that dumps into small intestine; endocrine & exocrine
Gallbladder: Store bile that dumps into small intestine; helps digest/absorb fats
Liver: Makes bile salts that also helps digest/absorb fats; does a lot
What does the spleen do? It’s very prone to ____.
- Filters blood as part of the immune system
- Lymph node
Very prone to bleeding
What are the retroperitoneal organs? They refer pain to ___.
SADPUCKER Suprarenal/adrenal glands Aorta & IVC Duodenum (except 1st part) Pancreas (except tail) Ureters Colon (only desc & ascending) Kidneys Esophagus Rectum Refers pain to the back
Sensory innervation of the peritoneum - relevance to appendicitis?
Visceral peritoneum is visceral afferent Parietal peritoneum is somatic afferent Appendicitis: referred pain only affects the visceral afferents, but when inflammation gets bad enough, it can reach the parietal peritoneum and suddenly cause sharp, stabbing pain
Unlike the pleura, the space between visceral and parietal peritoneum ____
is filled with fluid
You would perform an exploratory laporotomy for patients with ___ or ___.
Acute abdominal pain, because it indicates that the problem has affected the somatic afferent, so it must be bad. Blunt abdominal trauma, because it can cause a lot of bleeding into this space.
Three layers of fascia for the spermatic cord an what they’re continuous with
EXTERNAL FASCIA continuous with ext oblique aponeurosis
CREMASTER FASCIA continuous with the internal oblique muscle and aponeurosis
INTERNAL FASCIA continuous with the transversalis fascia
Nerves found between the external and internal oblique muscles:
ILIOINGUINAL NERVE from L1
- enters spermatic cord
- Innervates the int oblique & transversus abdominus
ILIOHYPOGASTRIC NERVE from L1
- more superior
- Innervates same muscles as ^
SUBCOSTAL NERVE from T12
Above the arcuate line, the anterior rectus sheath is made of _________.
Below the arcuate line, the anterior rectus sheath is made of ________.
Above: Ext oblique & int oblique aponeuroses
Below: Ext oblique aponeurosis; int oblique aponeurosis; abdominus transversalis aponeurosis
Where are the inferior epigastric vessels?
Between the rectus abdominis muscle and the posterior rectus sheath
Where is the ligamentum teres hepatis and what was it embryologically?
It’s in the round ligament of the liver; it’s the obliterated umbilical vein
What maneuver facilitates exploration of IVC, SMV, Rt renal vessels, and abdominal aorta?
Cattle Braasch maneuver
What maneuver facilitates exploration of abdominal aorta and left renal veins?
Mattox maneuver
Direct vs indirect inguinal hernias
DIRECT HERNIAS: Occurs medial to the inferior epigastric vessels; intestines herniate through a weak point in the abdominal wall. INDIRECT HERNIAS: lateral to inferior epigastric vessels; intestines herniate into the spermatic canal
Above the arcuate line, ____ & ___ are posterior to the rectus sheath
Internal oblique aponeurosis
Transversalis abdominis aponeurosis
If the aorta is occluded, what collateral can the rectus sheath use?
The rectus sheath still feed the lower body by using arterial circulation from the thoracic region via the superior & inferior epigastric arteries.
Superior epigastric artery is a continuation of _____
. Inferior epigastric artery is a branch of the ____.
Both are on the rectus abdominis.
Superior is a continuation of internal thoracic artery of thorax.
Inferior is a branch of the external iliac artery.
Boundaries of the epiploic foramen
Anterior - hepatoduodenal ligament
Posterior - IVC
Superior - caudate lobe of liver
Inferior - first part of duodenum
Fxn of abdominal wall muscles.
Transversus abdominis involved in forced expiration
Fxn of external oblique
Rotate ipsilaterally.
If your left side contracts, you rotate to the right
Woman has a severe peptic ulcer disease. She had a flat, firm, tender abdomen with guarding and rebound tenderness. Perforated peptic ulcer diagnosed and patient gets a laparotomy. Which of the following sites is least likely’ to show fluid collection?
Morison’s pouch
Rectouterine pouch
Paracolic gutter
Omental bursa
Greater sac
“Tender” –> somatic pain –> parietal peritoneum must be affected.
Stomach contents are coming out and touching the parietal peritoneum.
The greater sac is the answer because it’s pretty much everywhere; whereas, fluid collects in any of the other regions (pouches, gutters, lesser sac)
Umbilical folds
Lateral umbilical fold holds the inferior epigastric vessels, which anastomose with superior epigastric vessels to supply the abdominal wall.
Medial umbilical folds - obliterated umbilical artery that returned blood to placenta
Median umbilical fold- median umbilical ligament; urachus = remnant of allantois
Remnant of umbilical vein
Ligamentum teres of the liver
If you see ‘urachus’, think
Allantois
What two types of hernia are caused by developmental problems?
Indirect inguinal hernias - patent processus vaginalis
Umbilical hernia - failure of lateral fold closure
What 3 types of hernia have an anatomic/acquired cause?
Lumbar hernia
Femoral hernia
Direct inguinal hernia
What’s in the foregut?
- Mouth -> duodenum
- Liver
- Pancreas
- Galbladder
What artery feeds the foregut? Where is the lymphatic drainage for foregut organs?
Celiac trunk.
Lymph node is also here!
Parasympathetic to the foregut?
Preganglion: vagus nerve (CN X)
Postganglionics at the target organ
Sympathetic to the foregut?
Preganglion: IMLT5-T9 -> greater splanchnic nerves.
Postganglion: celiac ganglion
If you have hypogastric pain, that’s visceral pain in the hypogastric area. Where must it be originating from?
Can only be between the transverse colon and the anal canal
If you have epigastric pain, where could it be from?
The foregut derivatives all refer pain to epigastrium through the greater splanchnics.
Mouth, esophagus, stoamch duodenum
Liver
Pancreas
Gallbladder
Spleen
Celiac trunk’s major branches
- Left gastric artery
- Common hepatic artery
- Splenic artery
What two arteries are behind the stomach, and thus could be affected in a peptic or duodenal ulcer?
Splenic artery
Gastroduodenal artery
The folds of the stomach are called
Rugae
Stabbing in the _th/_th/_th rib is gonna rupture your spleen.
9th/10th/11th
Splenomegaly
Enlarged spleen –> excessive bleeding could kill you
Fxns of fetal liver
Cardiovascular (umbilical vein/artery)
Produces major hormones before gonads
Bile dissolves fat, but the enzymes that digest fat come from the
pancreas
Describe the portal system function
Everything absorbed in your GI goes to your portal veins
- > sends it to liver for metabolism
- > deliver this detoxified blood to the inferior vena cava
- > heart
LARP
Left vagus nerve is anterior
Right vagus nerve is posterior
Almost everything in the GI is endodermal origin except
spleen - that’s mesoderm because it forms all the blood
Hepatosplenomegaly
Cirrhosis or hepatitis swells up the liver –> blood backs up to the spleen
Cholelithiasis
Gallstones (“lith”=stone)
Choledocholithiaseis
Gallstones in duct
“docho”=duct
Cholecystitis
Inflammation of the gallbladder
Common locations for gallstones to get stuck and consequences
Cystic duct/neck of gallbladder: pain, but no jaundice.
Start of common bile duct: pain with jaundice bc bile backs up to liver
Ampulla of vater/Hepatopancreatic ampulla: pancreatic pain with jaundice because backup of pancreatic enzymes + backup of bile to liver.
A woman with epigastric pain that migrates right and posteriorly toward the scapula. Has cholecystitis and large gallstone with no jaundice. What structure is the gallstone most likely located in?
Common bile duct; Hartmann’s pouch; Left hepatic duct; Pancreatic duct; Right hepatic duct
If there’s no jaundice, then outflow to liver must not be blocked. Only Hartmann’s pouch (an intestine thing) doesn’t block liver.
Ligament of Treitz- what does it connect? what is its clinical significance?
Holds the duodenojejunal flexure up to the connective tissue.
Clinical significance: prevents the midgut from rotating and causing a small bowel obstruction.
How can you distinguish between the ileum and the jejunum?
Ileum has shorter vasa recta and more arcades.
Jejunum has longer vasa recta and fewer arcdes.
Small intestine has what two kinds of muscles? Where is the plexus?
Between the circular (more superficial) and longitudinal muscles.
Hirschsprung disease/Congenital megacolon
Nerve cells (from neural crest cells) in the colon never form, so the colon can’t move stuff.
Porto-caval anastomoses - where are they? what are they between? what are the consequences of each if pressure is elevated
Ways that the portal system connects to your systemic circulation.
-
Gastroesophageal jxn around cardia of stomach
- Left gastric vein (portal) + Esophageal vein of azygous system (sys)
- Esophageal varices
-
Anorectal jxn
- Superior rectal vein (portal) + middle&inferior rectal vein (systemic)
- Varices at anorectal jxn
-
Anterior abdominal wall around umbilicus
-
Para umbilical veins (portal) + veins of ant abd wall (systemic)
- Veins of ant abd wall = superficial epigastric veins
- Caput medusae at umbilicus
- Umbilical vein in the round ligament can re-canalize and contribute to caput.
-
Para umbilical veins (portal) + veins of ant abd wall (systemic)
Hemorrhoids: dilated veins around the anal canal.
Which is more painful - internal or external hemorrhoids? why?
Above the pectinate line, the anal canal is innervated by visceral afferents. Thus, internal hemorrhoids aren’t painful if they bleed.
External hemorrhoids are painful because they are below the pectinate line.
Both are hindgut, so they’re innervated by pelvic and splanchnicnerves.
There is no scarpa’s fascia above the
Umbilicus region
What layers would you go through if you got stabbed in the left epigastric region?
Above arcuate line.
- Skin
- Superficial fascia (bc above umbilical region)
-
Anterior rectus sheath
- Aponeurosis of ext oblique
- Apo of int oblique
- Rectus abdominus
-
Posterior rectus sheath
- Aponeurosis of int oblique
- Aponeurosis of transverse abdominus
- Transversalis fascia
- Parietal peritoneum
What layers would I go through if stabbed in the left hypogastric region?
Below the arcuate line.
- Skin
- Camper’s fascia
- Scarpa’s fascia
- External oblique muscle
- Internal oblique muscle
- Transversus abdominus muscle
- Rectus abdominus muscle
- Transversalis fascia
- Parietal peritoneum
The celiac trunk supplies the foregut. Which organs of the forgut are ALSO supplied by the SMA?
Duodenum (with SMA)
Pancreas (with SMA)
The suprarenal artery comes off the
inferior phrenic artery
Functions of adult liver
Anabolic biochemistry
Detoxification/drug metabolism
Bile secretion
Fat storage + fat-soluble vitamins
Ampulla vater
The junction between the main pancreatic duct and common bile duct
Not the same as the accessory pancreatic duct, which drains directly into the duodenum via the minor duodenal papilla.
Describe fat digestion
Liver makes fat-emulsifying bile that gets stored in the gallbladder and sent to the duodenum.
Pancreas makes lipase to break down fats.
Cholangitis
Inflammation of the biliary tract from obstruction
3 important characteristics of the colon/large intestine
Teniae coli are longitudinal muscle in the large intestine
Omental appendages are all over the colon, but absent in the rectum
Haustra
The crura separates the upper GI from the lower GI. What is it derived from?
Dorsal mesentery of esophagus
Gallstone ileus
Gallstone is lodged in the ileocecal valve because it perforated through the wall of the gallbladder into the duodenum.
Appendicitis pain
Referred pain: somatic pain caused by visceral afferents via lesser splanchnic to DRG -> umbilical pain
McBurney’s point: near appendix; peritoneum irritated
Psoas sign
Psoas=hip flexors
Stretching someone’s leg to see if it hurts because the psoas muscle would touch the appendix –> indicates appendicitis.
Adrenal medulla
Specialized sympathetic post-ganglionic cells that secrete epinephrine & norepinehphrine (catecholamines).
Because it’s a peripheral nerve, it’s derived from neural crest.
Blood supply for adrenal gland
Superior suprapraneal artery off the inferior phrenic artery
Middle suprarenal artery off the aorta
Inferior suprarenal artery off the renal artery
Which of the retroperitoneal organs are secondary?
- Ascending colon
- Descending colon
- Duodenum
- Pancreas
Endocrine
Signaling released in the blood stream to reach distant targets.
Includes thyroid gland, adrenal gland, and pancreas.
Adrenal cortex
An actual endocrine gland that releases their ‘neurotransmitter’ directly into the blood stream (as opposed to through axons like the medulla) for a big synchronized sympathetic response.
Still derived from neural crest
