Lecture 10 (abdomen) pt 3 Flashcards
Is McBurney’s point somatic or visceral pain?
Somatic
Initial pain around T10 dermatome (periumbilical) that transitions to RLQ pain is likely what?
Appendicitis
Esophagus passes through diaphragm; initially it’s posterior to the trachea and ___________________.
As aorta arches posteriorly and slightly left, the aorta becomes more posterior than the ______________ and _____________
ascending aorta; esophagus and IVC.
True or false: Small part of esophagus is intraperitoneal but most is retroperitoneal
True
What is the esophageal hiatus also called?
(Distal) esophageal sphincter
1) What is the esophagogastric junction/ where is it?
2) Is the esophagus retroperitoneal or intraperitoneal in the abdomen?
3) What is the difference between the gastric mucosa and esophageal mucosa?
1) It’s the “Z” line; abrupt transition in mucosa; left of the midline, 7th costal cartilage/T11
2) Retroperitoneal in abdomen
3) Esophageal mucosa is not well-suited to high-acidity like gastric juices, gastric mucosa is because it has tight junctions and lots of mucous cells.
1) What makes up the esophageal muscle layers?
2) What are the 3 esophageal muscle layers?
-Somatic blended into visceral muscle
1) Superior 1/3: voluntary m.
2) Middle 1/3: transition
3) Inferior 1/3: smooth m.
What part of the stomach does the esophagus enter? What is right next to that area?
Cardia; cardial notch
List 4 clinical applications/ pathologies that can happen to the esophagus
1) GERD
2) Hiatal hernia
3) Barrett’s esophagus
4) Esophageal cancer
What is a hiatal hernia? What are the two types?
Part of the stomach has herniated through the diaphragm and into the chest:
1) Para-esophageal
2) Sliding
1) What is the difference between gastric and duodenal peptic ulcers?
2) What is the most common cause of peptic ulcers? What can help?
1) Gastric peptic ulcers occur inside stomach, duodenal peptic ulcers occur on inside of upper portion of duodenum of small intestine.
2) Most commonly caused by H. pylori (not stress or spicy foods), NSAIDs can help.
List the 4 parts of the duodenum
1st) Superior part
2nd) Descending part: bile and main pancreatic duct enters posteromedial wall via hepatopancreatic ampulla
3rd) Inferior (horizontal or third) part: between aorta and SMA
4th) Ascending (4th) part
The bile and main pancreatic duct enter the posteromedial wall via hepatopancreatic ampulla at what part of the small intestine?
Descending (2nd) part of the duodenum
What part of the small intestine is between aorta and SMA?
Inferior (horizontal/ third) part of the duodenum
What are the first 2cm of the duodenum called? What is unique about it?
Ampulla or duodenal cap; it’s “free” suspended by mesentery
What does the hepatoduodenal ligament containing the portal triad demarcate?
The end of the ampulla or duodenal cap (first 2cm of duodenum) being suspended freely be mesentery; it’s intraperitoneal after this point
Most of duodenum is “fixed” in _______________ space
retroperitoneal
1) Suspensory ligament of duodenum (ligament of Treitz aka suspensory muscle of the duodenum) is located where?
2) What is its significance?
1) Duodenojejunal flexure
2) Clinically divides “upper GI” from “lower GI” tract
What clinically divides “Upper GI” from “lower GI” tract?
Suspensory ligament of duodenum
(aka ligament of Treitz aka suspensory muscle of the duodenoum)
The area between what two junctions makes up the jejunum and ileum?
Duodenojejunal junction to ileocecal junction
1) What artery has branches that runs between layers of mesentery in the jejunum and iliac regions?
2) Where does it go?
1) Superior mesenteric artery (SMA)
2) Sends many branch arteries to jejunum & ilium, unite to form loops or arches called arterial arcades which gives rise to vasa recta
What nervous system controls the jejunum and ilium?
Enteric nervous system
Describe the relationship between the cecum, the mesentery, and the peritoneum
No mesentery, but entirely covered by peritoneum, and can be lifted freely
1) Where is the appendix and does it have mesentery?
2) Where is McBurney point?
1) Has a small mesentery, location varies
2) 1/3 distance along line from right ASIS to umbilicus
Where does the appendix enter the small intestine?
At the ileocecal junction into the cecum
Semilunar folds and haustra are characteristics of what part of the intestine?
Cecum
Briefly describe the appendix and cecum
-Appendix: mesentery, mobile, location varies
-Cecum: nearly covered in peritoneum, no mesentery, but can be elevated
1) Is the ascending colon retroperitoneal or intraperitoneal?
2) What is its feature? What artery supplies this pt of the colon?
3) What flexure is here?
1) Retroperitoneal
2) Right paracolic gutter; SMA
3) Right colic or hepatic flexure
1) Describe the mobility of the transverse colon. Why is it this way?
2) What supplies this part of the colon?
3) What flexure is here?
1) Mobile due to transverse mesocolon, often swings inferior to umbilicus or below
2) Mostly SMA
3) Left colic or splenic flexure
1) Is the descending colon retroperitoneal or intraperitoneal?
2) What is its feature?
3) What supplies this part of the colon with blood?
1) Retroperitoneal
2) Left paracolic gutter
3) IMA
1) Where is the sigmoid colon?
2) What signifies grossly sigmoid colon?
3) Does it have mesentery? Is it mobile? What supplies this pt of the colon with blood?
1) Descending colon to rectum, “S” shaped
2) Termination of tinea coli
3) Mesentery, mobile, IMA
Everything below the umbilicus drains where?
To inguinal nodes
All lymph drainage of the abdomen ultimately goes where?
To thoracic duct
True or false: the abdomen has a rich supply of lymph nodes and spread of infection and or metastatic spread of cancer can be vast
True
1) What sympathetic fibers innervate the GI tract? Where do they come from?
2) What parasympathetic fibers innervate the GI tract and where do they come from?
1) Thoracic and lumbar splanchnic nerves; prevertebral ganglia
2) From vagal trunk; plexuses (symp & parasym)
All the lymph vessels, arteries, and nerves that supply the large intestine are where?
Within the mesentery/ retroperitoneal
(reiterating)
1) What type of sympathetic outflow is the symp. innervation to the GI tract??
2) What nerves are these? Where do they go? What do they do?
1) Thoracolumbar sympathetic outflow
2) Splanchnic nerves to pre-vertebral/pre-aortic ganglia and plexuses; moderate enteric nervous system
(reiterating)
1) What is the parasympathetic outflow to the GI tract? What plexus and ganglia do they go to?
2) What do they do?
1) Vagus and S2-4 spinal nerves to pre-aortic plexuses, Intramural ganglia
2) Moderate enteric nervous system
1) Is visceral afferent innervation to the GI tract always unconscious? If so, why? If not, what it is perceived as?
2) How does visceral afferent innervation travel?
1) Visceral reflexes are autonomic and unconscious; visceral pain, distention, or ischemia may reach conscious level and perceived as hunger or nausea
2) Travels retrograde via para and sympathetic fibers to spinal cord segment where the visceral motor fibers originate; poorly localized
1) What 4 conditions can affect the large intestine?
2) Where is the base of the appendix?
1) Diverticulosis, appendicitis, ischemic colitis, and hypovolemia
2) At McBurney point
1) What is ischemic colitis?
2) What is the area most affected by this called?
1) Reduced blood flow
2) “Water shed” area.
What can cause hypovolemia?
Hemorrhage or significant volume depletion from dehydration
What are the two anatomical arterial transitions in the gut
1) Duodenum has artery supply from 2 different vessels
-1st and 2nd part via celiac trunk via supraduodenal and gastroduodenal aa.
-3rd and 4th part of the duodenum to splenic flexure of colon via SMA via pancreaticoduodenal a.
2) Splenic or left flexure of the colon
-SMA and IMA
Duodenum has artery supply from 2 different vessels; what are they?
1) 1st and 2nd part via celiac trunk via supraduodenal and gastroduodenal aa.
2) 3rd and 4th part of the duodenum to splenic flexure of colon via SMA via pancreaticoduodenal a.
What two things supply the splenic or left flexure of the colon?
SMA and IMA
1) Describe the mobility of the spleen
2) What type of organ is it?
3) Is it intraperitoneal or retroperitoneal?
4) Where is it normally located? Where does it not descend below?
5) What vein drains it?
1) Mobile
2) Lymphoid organ
3) Intraperitoneal; suspended via mesentery
4) Normally rests on the left colic flexure and does not descend below costal arch
5) Drains via portal vein
1) What type of gland is the pancreas?
2) Where is it? Is it retroperitoneal or intraperitoneal?
3) What are its three parts?
1) Accessory digestive gland
2) Retroperitoneal (almost all) against posterior wall
3) Head, body, tail
1) Where is the tail of the pancreas and what’s unique about it?
2) Where does the pancreas drain lymph?
1) Adjacent to splenic hilum; only part of pancreas that’s intraperitoneal
2) Towards the midline
1) What forms the posterior wall of the omental bursa?
2) What about the anterior wall?
1) Pancreas
2) Lesser omentum and the stomach.
1) When can gallbladder stones be a big problem?
2) Why?
1) When they descend and obstruct the major pancreatic ampulla and sphincter
2) There will be backup of both the bile system, causing jaundice, and the pancreatic sphincter, causing pancreatitis (most common cause)
1) What does the sphincter of the bile duct do?
2) What does the sphincter of the pancreatic duct do?
3) What is the hepatopancreatic sphincter also called?
1) Controls flow of bile
2) Prevents reflux of bile into pancreatic duct
3) “Sphincter of Oddi”
What are the demographics of the average pt with gallbladder stones?
Overweight, female, over 40
The second most common cause of pancreatitis is what?
Alcohol
Name two organs that are mobile because they have mesentery.
Spleen and stomach
1) What are the anatomic divisions of the liver?
2) What are the functional (portal/bile secretion lobes) divisions of the liver?
1) 4 lobes: right + caudate & quadrate + left lobe.
2) Divided into the independent right and left portal lobes.
1) What two things form the left sagittal fissure?
2) What does this fissure do?
1) Round ligament (umbilical vein) & ligamentum venosum (ductus venosus)
2) Separates the right and left livers (portal lobes)
What is the right sagittal fissure?
The continuous groove formed by the fossa for the gall bladder anteriorly and the IVC fossa posteriorly.
Name 2 fetal structures that have remnants after birth and help form the left sagittal fissure
1) Round ligament (umbilical vein)
2) Ligamentum venosum (ductus venosus)
What acts as the lungs for fetuses?
Placenta
1) What uses ductus venous to bypass the fetal liver?
2) What does this turn into after birth?
1) Umbilical vein
2) Round ligament & ligamentum venous
1) What bypasses the fetal lungs?
2) What does it turn into after birth?
1) Ductus arteriosus
2) Ligamentum arteriosus
-What two main things supply the liver with blood
Describe the oxygenation and origin of the blood in each, and how much of the liver each supplies.
-What do these two things divide into?
1) Hepatic Portal Vein (HPV) -75%
-Poorly oxygenated, nutrient dense blood from GI track
2) Hepatic Artery (HA) – 25%
-Oxygen rick blood from systemic circulation
-Both divide into right and left branches at or near portal hepatis then form Segmental branches
HPV (hepatic portal vein) and HA (hepatic artery) divide into right and left branches at or near ___________________ then form ________________ branches
portal hepatis; segmental branches
What drains the liver of blood between its segments? Where does it go?
Hepatic veins drain into IVC
Describe the “in” and “out” of the liver
1) IN: Hepatic portal veins and hepatic artery
2) OUT: Hepatic veins + bile collecting system
1) What skips the liver?
2) What drains the liver of blood?
1) Systemic IVC
2) Hepatic vein (NOT the hepatic portal vein)
What make up the interlobular portal triads between liver lobules?
Hep artery, portal vein, bile duct
1) Portal and hepatic artery blood percolates thru sinusoids to where? Then where?
2) Bile flows from hepatocytes thru ducts to where? Then where?
1) Central vein to hepatic vein
2) Portal triad and then common bile duct
1) What drains the abdominal viscera of blood? Where does it distribute that blood to, and in what pattern?
2) What is the portosystemic anastomosis?
1) Hepatic portal vein drains abdominal viscera; distributes in a segmental pattern to the sinusoids of the lobules
2) Portal venous system communicates with systemic veinous system
Portosystemic anastomosis:
1) What anastomose with the left gastric vein (portal)?
2) What is it called when this anastomosing area is dilated?
1) Esophageal veins via azygos v. (systemic)
2) Esophageal varices
Portosystemic anastomosis:
1) What anastomose with the superficial epigastric veins (systemic)?
2) What is it called when this anastomosing area is dilated?
1) Para umbilical veins of anterior abdominal wall (portal)
2) Caput medusa
Portosystemic anastomosis:
1) What anastomose with superior rectal veins continuing as the IMV (portal)?
2) What is it called when this anastomosing area is dilated?
1) Inferior and middle rectal veins via IVC (systemic)
2) Hemorrhoids
[Hepatic] portal HTN results in what?
Dilated caps at above anastomosis, rupture, and hemorrhage
Portosystemic anastomosis:
What anastomose with retroperitoneal veins (systemic)?
Twigs of colic veins (portal)
1) Is the left gastric vein considered portal or systemic in its portosystemic anastomosis?
2) What about the superficial epigastric veins?
3) What about the retroperitoneal veins?
1) Portal
2) Systemic
3) Systemic
1) What causes cirrhosis of the liver to occur frequently because of chronic alcohol use?
2) What causes esophageal varices? What can happen to them and how can they be treated?
1) Hepatocytes are destroyed and replaced by fibrous tissue leading to portal HTN
2) Liver disease (often alcoholic liver disease); may rupture, may be viewed and treated by endoscope…sclerosis
1) What causes periumbilical varices or caput medusa and what are they a PE sign of?
2) What are hemorrhoids? What can cause them?
1) Epigastric veins and periumbilical veins; hepatic portal HTN or disease
2) Varices at anal region of anastomosis of superior rectal veins and rectal veins; pregnancy, etc.
1) What is the hepatic nerve plexus derived from?
2) What do the hepatic nerve plexus nerves accompany?
3) Where do the sympathetic fibers here come from?
4) What about the parasympathetic fibers?
1) Celiac plexus
2) Branches of vessels
3) Celiac plexus
4) Parasympathetic fibers from CN X, Vagus n. via anterior and posterior Vagal trunks (from esophageal plexus)
1) What is cholelithiasis?
2) What is cholecystitis?
1) Stones in gall bladder
2) Inflammation/ infection of gall bladder often due to blockage of cystic duct
1) What is cholangitis?
2) What is pancreatitis?
1) A redness and swelling (inflammation) of the bile duct system that results from bacterial infection.
2) Inflammation of pancreas, often related to blocked duct by stone or alcohol use
1) Gallstones can occur in biliary passages; what is the most common location for impaction?
2) What is a cholecystectomy?
1) The narrowest site, the ampulla sphincter.
2) Removal of the gall bladder due to biliary colic
1) What artery should you keep in mind during a cholecystectomy?
2) What anatomically define the cystohepatic triangle?
1) Cystic a. most commonly arises off the right hepatic a. in the cystohepatic triangle (Calot triangle)
2) Cystic duct, common hepatic duct, and inferior surface of the liver
-Must be ID’d early in procedure to safeguards these structures, especially with anatomic variations
1) Where are the kidneys?
2) Where is the inferior pole of the kidneys? What varies between the two kidneys?
1) Lie posterior abdominal wall T-12 to L3 (umbilicus ~L3)
2) About level of umbilicus; right kidney a bit lower
What anatomically defines the cystohepatic triangle? (inferiorly, medially, and superiorly)
1) Inferiorly by cystic duct
2) Medially by the common hepatic duct
3) Superiorly by the inferior surface of the liver
-Must be ID’d early in cholecystectomy to safeguards these structures, especially with anatomic variations
