Abdomen pt. 2 Flashcards
Fascia contributing to the abdomen from the Transversus Abdominis Muscle.
-Deep to this is pre-peritoneal Fat
Transversalis Fascia
Which abdomen is weaker, upper or lower?
Lower is weaker than upper. In the lower abdomen, aponeuroses don’t go completely around the abdominal aorta. They combine and go anterior to the Rectus Abdominis, but not posterior.
-Hernias are more likely to occur here due to incomplete Rectus Sheath not bracing these muscles.
-Has rectus sheath anteriorly and posteriorly
-External Abdominal Oblique aponeurosis runs in front
-Internal Abdominal Oblique aponeurosis splits, and some go in font and some go behind
-Transversus Abdominis aponeurosis fibers run behind
Upper Abdomen
The deepest layer; the body wall itself. Lines the internal abdominal cavity
Parietal Peritoneum
Connects the peritoneum posteriorly with a visceral structure. Fold of peritoneum that sticks out. Ligament that attaches something in back to something in front.
Mesentery
Attaches the stomach to the liver
Lesser Omentum
Joins the stomach, and then flops down, folds on itself to wrap around transverse colon.
-Has to be kept warm during surgery, can lower a patient’s body temp
-Fatty Apron
-Has a free end
Greater Omentum
Runs from posterior body wall, has parietal peritoneum on it.
-Attaches into Transverse Colon
Transverse Mesocolon
A sac between the stomach and pancreas, has liver above it and transverse colon below.
-Cushion for organs to rest on
-Has an opening formed by the free edge of Lesser Omentum, called the Epiploic Foramen of Winslow.
Omental Bursa
The entrance into the Omental Bursa.
-Good place for infections to hide (blind pouch)
-Acts as a water-bed for organs to rest on
-Found on the Right side of the body at the attachment between the Duodenum and Liver
-Lesser Omentum lies in front and IVC is behind
Epiploic Foramen of Winslow
Liver is suspended from Diaphragm. LO joins Liver to stomach, so stomach is suspended from Liver via LO. Then, Transverse Colon. GO forms the fold (Apron of fat) that overlies abdominal viscera.
Omentum
A vertical layer of peritoneum between the right and left lobes of the liver.
-Attaches to the posterior side of the abdominal wall
-In fetal life, was the Umbilical Vein
Ligamentum Teres Hepatis (Round Ligament of the Liver) & Falciform Ligament
-Cardia: portion that joins esophagus
-Fundus: Part that bulges, touches spleen
-Body: biggest portion
-Pylorus: termination into the duodenum
-Attached to the liver via Lesser Omentum
Stomach
Hidden from view unless enlarged. Tucked in under 12th rib. Have to retract viscera to view.
Spleen
Fits snugly between right lobe and quadrate lobe in fossa for the gallbladder.
Gallbladder
-Attached between right and left lobe. Vertically running slip of peritoneum. Attaches to the anterior body wall from the posterior side.
-Supports the vein running in the free edge of the Falciform Ligament called the Ligamentum Teres Hepatis (old Umbilical vein in-utero)
Falciform Ligament
Found to the left of the IVC where it passes through the liver.
-IVC passes between this and the Right Lobe
Caudate Lobe
-C Shaped with concavity facing towards the left.
-Comes off the pyloric portion of stomach, then get to portion lying horizontally called the Superior Portion of the Duodenum or the Duodenal Bulb. Significant for dz - peptic ulcers occur here (70% of cases occur here).
-Descending Portion of the Duodenum
-Transverse Portion of the Duodenum
-Ascending Portion of the Duodenum
These are about the level of the xiphoid process
Duodenum
Drain the liver. Come together to form the Common Hepatic Duct.
Right/Left Hepatic Ducts
Created by the Right and Left Hepatic Ducts, joins with the Cystic Duct (drains gallbladder)
Common Hepatic Duct
Purpose is for storage and concentration of bile. Liver produces dilute bile, excretes it into ducts where it loses water and exits as more concentrated. Bile is necessary for digesting fats (acts as an emulsifying agent).
Gallbladder
Cystic Duct & the Common Hepatic Duct pass behind the Duodenal Bulb and form the _______
-Terminates in the Descending portion of the Duodenum
Common Bile Duct
-Head of the pancreas fits right into the C of the Duodenum
-Ducts come off of the pancreas: Main Pancreatic Duct (Duct of Wirsung) and an Accessory Pancreatic Duct (Duct of Santorini). Not everyone has an Accessory Duct.
-Terminates above and behind the termination of the Common Bile Duct.
-Pathology of the pancreas, patient will retain bile, leading to jaundice. Blockage of flow of bile duct. Also blocks flow of pancreatic duct and issues with enzymes that breakdown fats, carbs, and proteins.
Pancreas
Common Bile Duct and Main Pancreatic Duct have the same drainage point, called _____.
-Has stripes called the Sphincter of Oddi. Muscle that regulates flow from Ducts. Relaxes = inc flow. tightens = reduced flow. Spasms with opioid use, causing discomfort (stuff backs up into system due to closed sphincter)
Ampullae of Vater (within Descending Duodenum)
-Anterior Surface is covered by Visceral peritoneum
-2nd and 3rd parts (Descending and Transverse) are Retroperitoneal.
Duodenum
Retroperitoneal except for the Tail
Pancreas
Entirely retroperitoneal, sit up against the posterior body wall.
-Not covered. by peritoneum
Kidneys
Look like fat perched on top of the kidneys
-blood supply is from the Middle (aorta), Inferior (Renal Artery), and Superior (diaphragmatic portion of the vessels) Suprarenal Arteries.
Adrenal Glands
Interior portion. Produces catecholamines (Epi - tachycardia & norepi - HTN). Fight or flight to inc blood flow in some way via SNS Stimulation.
Medulla (Adrenal Glands)
Exterior portion:
-Mineralocorticoids: Hormones that work with electrolyte substances (Na, K+)
-Glucocorticoids: manage BG
Cortex (Adrenal Glands)
Proximal ⅓ of the SI past the Duodenum
-Mesentery proper supports it
Jejunum (of the Small Bowel)
Distal ⅔ of the SI past the Duodenum
-Larger and longer
-Mesentery proper supports it, and it is more fatty here.
-More absorption occurs here
Ileum (of the Small Bowel)
Beginning of the Large Bowel
-Has a valve where the Ileum terminates that regulates flow into the large bowel.
Cecum
Ascending colon -> Transverse colon -> Descending Colon -> Sigmoid Colon (S-Shaped) -> terminate in the rectum and the anal canal
Large Bowel Flow
-Large Bowel Corner on the right side
-Occurs underneath the Liver
Hepatic Flexure (Right Colic Flexure)
-Large Bowel Corner on the left side
-Occurs underneath the Spleen
Splenic Flexure (Left Colic Flexure)
Can be surgically removed or involuted over time with aging. Appendix has its own layer of peritoneum called the Meso-Appendix
Vermiform Appendix
Long line of longitudinal shaped muscles that follows large bowel from beginning to end. Helps with peristalsis. Moves waste products on through the bowel.
-Forms pockets called Haustrae
Taenia Coli
Fat tags you see around the large bowel.
Appendices Epiploica
Drains blood from the middle portion of abd cavity and abd viscera
Superior Mesenteric Vein
Drains the distal bowel, lower ⅓ of the bowel below the diaphragm
-Drains into the Splenic Vein
Inferior Mesenteric Vein
Most proximal part. Upper ⅓ of abdominal viscera. Runs along body/tail of the Pancreas. Drains pancreatic veins and gastric veins.
-Joins with Inferior Mesenteric Vein
-Then, joins with Superior Mesenteric Vein
Splenic Vein
Inferior Mesenteric Vein drains into the Splenic Vein. Then, the Splenic Vein drains into the Superior Mesenteric Vein to form _____.
-Takes blood from all these systems, penetrates the liver via the Porta Hepatis (Liver Hilum - where blood comes and goes). Blood from GI tract is channeled to Liver, where the blood is filtered, synthesize raw materials from GI tract like Amino Acids into proteins, etc.
Hepatic Portal Vein
Once it enters the liver via the Porta Hepatis, it immediately divides into a right and left Hepatic Portal Vein, which drain into a Liver Lobule (functional unit of the Liver), then into Hepatic Sinusoids, which drain into the Central Vein
Hepatic Portal Vein
Substances are taken to the Central Vein (Hepatic Venule), and then we form veins to take blood back to the IVC
-Right, Middle, and Left
-Terminate at the level of the notch in the liver for the IVC, to drain into the IVC to bring blood back up to the heart for recycling.
Hepatic Veins
dz of the liver (Hepatitis C, etc) leads to inflammation of liver, swelling, and scarring over of the liver.
-Esophageal veins are being overloaded with blood. Blood backs up into veins causing congestion, so veins dilate, making the walls even thinner, and can tear easily. Patient also doesn’t clot well due to issues with coagulation. Lack of Vit K.
-Occlusion of the hepatic portal vein causes blood to take another route (portal system anastomosis) around the Liver to try to get back to the heart. Causes veins to join hepatic portal system like L or R gastric veins. Problem is these aren’t very big and become overloaded and swell.
-All this is happening because blood cannot get through the liver due to it being occluded. Blood takes another course to get back to the heart. One of these courses is through the esophageal veins which are very tiny and cannot accommodate the congestion.
-Patients have problems with esophageal bleeding.
Esophageal Varices
Portal HTN -> difficulty getting blood to the liver, so it backs up into abdominal viscera which start swelling with fluid. Then, they start “weeping” fluid into abdominal cavity, showing up as a belly full of fluid.
Ascites
