Module 9A - Abdomen Flashcards
Abdominal cavity location
Between thoracic diaphragm and pelvic inlet
What protects the abdominal organs?
Lower ribs
Muscular abdominal wall
Pelvis
Transtubercular plane location
Level of iliac tubercles and body of L5
Subcostal plane location
Level of inferior borders of 10th costal cartilage on each side
9 region system of abdomen
Hypochondriac (R/L) Lumbar (R/L) Inguinal (R/L) Epigastric Umbilical Hypogastric
Two horizontal planes of abdomen (9 region system)
Transtubercular
Subcostal
Two vertical planes of abdomen (9 region system)
R/L midclavicular planes
Horizontal plane of abdomen (quadrant system)
Transumbilical plane
Transumbilical plane location
Level of umbilicus and L3-L4 disc space
Vertical plane of abdomen (quadrant system)
Median plane
RUQ contents
- Liver/gallbladder
- Pylorus of stomach, duodenum, ascending/R half of transverse colon
- Head of pancreas
- R kidney
LUQ contents
- L lobe of liver, jejunum, ileum, descending/L half of transverse colon
- Spleen
- Body & tail of pancreas
- L kidney
RLQ contents
- Cecum, inferior portion of ascending colon, appendix
- R ureter, bladder (if distended)
- R ovary, R uterine tube, uterus (if enlarged)
- Spermatic cord - abdominal part
LLQ contents
- Sigmoid colon, inferior portion of descending colon
- L ureter, bladder (if distended)
- L ovary, L uterine tube, uterus (if enlarged)
- Spermatic cord - abdominal part
Abdominal superficial fascia is composed of 2 layers:
- Camper’s fascia (fatty)
- Scarpa’s fascia (membranous, inner layer)
Transverse fascia of abdominal wall
- Lines inner portion of transverse abdominal wall
- Continous with linea alba
Anterolateral abdominal wall is composed of:
- Skin
- Superficial fascia (Camper’s, Scarpa’s)
- Deep fascia
- Muscles
- Transverse fascia
- Extraperitoneal fat
- Parietal and visceral peritoneal layers
Muscles of anterolateral abdominal wall
External oblique Internal oblique Transverse abdominal Rectus abdominis Pyramidalis
External oblique attachments
Ribs 5-12 + linea alba/anterior half of iliac crest
External oblique innervation
Thoracic nerves (T5-T12) *NOTE: T12 nerve is called subcostal nerve
External oblique actions
Flex and rotate trunk
Compress viscera (assists w/expiration)
Support viscera/spine
Inguinal ligament is formed by:
Inferior aponeuroses of external oblique (fold back on itself)
Internal oblique attachments
Thoracolumbar fascia/anterior iliac crest/lateral inguinal ligament + ribs 10-12/linea alba
Internal oblique innervation
Thoracic nerves (T6-12) and first lumbar nerves
Internal oblique actions
Flex and rotate trunk
Compress viscera (assists w/expiration)
Support viscera/spine
Transverse abdominal attachments
Costal cartilage 7-12/TL fascia/iliac crest + linea alba
Transverse abdominal innervation
Thoracic nerves (T6-12) and first lumbar nerves
Transverse abdominal actions
Compress viscera (assists w/expiration) Support viscera/spine
Rectus abdominis attachments
Costal cartilages 5-7/xiphoid process + pubic symphysis/crest
Rectus abdominis innervation
Thoracic nerves (T6-T12)
Rectus abdominis actions
Flexes trunk
Compress viscera (assists w/expiration)
Support viscera/spine
Rectus sheath is formed by aponeuroses of:
External oblique
Internal oblique
Transverse abdominal
Rectus sheath encloses:
Rectus abdominis
Arcuate line location
Between level of umbilicus and pubic symphysis
Above the arcuate line:
Posterior portion of rectus sheath covers rectus abdominis
Below the arcuate line:
Rectus sheath travels anterior to rectus abdominis
Linea alba
Fibrous band of connective tissue located between the R/L rectus abdominis muscles
Linea alba is attachment for:
Oblique and transverse abdominal muscles
Inguinal ligament extends between:
ASIS and pubic tubercle
Inguinal ligament is formed by:
Folded aponeurosis of external oblique
Inguinal canal contents
Males: spermatic cord, ilioinguinal nerve
Females: round ligament of uterus, ilioinguinal nerve
Inguinal canal - anterior/posterior/superior/inferior borders
- Anterior: aponeurosis of external & internal oblique
- Posterior: transverse fascia
- Superior: Fibers of transverse abdominal and internal oblique
- Inferior: inguinal ligament (formed by inferior fold of external oblique)
Two openings to the inguinal canal:
Superficial (external) ring
Deep (internal) ring
Superficial ring of inguinal canal formed by:
An arch in external oblique aponeurosis
Deep ring of inguinal canal formed by:
Transverse fascia
Indirect inguinal hernia
Bowel protrudes through deep ring and descends through inguinal canal
Direct inguinal hernia
Bowel protrudes through defect in anterior abdominal wall
MC site of direct inguinal hernia
Hesselbach’s triangle
Hesselbach’s triangle borders
Lateral border of rectus abdominis
Inguinal ligament
Inferior epigastric artery/vein
Mesentary
- Double layered fold of peritoneum
- Suspends or connects organ to posterior abdominal wall
- Contains blood vessels, lymph vessels, nerves
Greater omentum
- Peritoneal fold that hangs down from greater curvature of abdomen
- Loops back up to attach to transverse colon
Lesser omentum
-Double layer of peritoneum that attaches to stomach and proximal duodenum and then attaches to liver
Peritoneal ligament
Doubled layer of peritoneum that attaches an organ to the abdominal wall or another organ
Two examples of peritoneal ligament
Falciform ligament (liver to anterior abdominal wall) Gastrosplenic ligament (spleen to stomach)
Intraperitoneal organs
- Suspended and covered anteriorly/posteriorly by peritoneum
- Did not invaginate into peritoneum during development
Retroperitoneal organs
- Covered anteriorly by one layer of peritoneum
- Did not invaginate into peritoneum during development
3 divisions of abdominal viscera
Foregut
Midgut
Hindgut
Foregut - boundaries and blood supply
Oropharynx to hepatopancreatic ampulla
Celiac trunk
Midgut - boundaries and blood supply
Hepatopancreatic ampulla to distal 1/3 transverse colon
Superior mesenteric artery
Hindgut - boundaries and blood supply
Distal 1/3 transverse colon to anus
Inferior mesenteric artery
Esophagus definition
Muscular tube connects pharynx to stomach
Esophagus passes through diaphragm in _____
Esophageal hiatus
Upper esophageal sphincter location and muscles
- Junction of pharynx and esophagus
- Inferior pharyngeal constrictors and cricopharyngeus muscles
Lower esophageal sphincter location and muscles
- Junction of esophagus and stomach
- Smooth muscle
Divisions of stomach
Cardia
Fundus
Body
Pylorus
Muscular layers of stomach
Oblique
Circular
Longitudinal
Rugae
- Gastric folds
- Large longitudinal in mucosal folds of stomach
- Will flatten out with food in stomach
Pyloric sphincter
Connects stomach to small intestine
Divisions of small intestine
Duodenum
Jejunum
Ileum
Duodenum
- Proximal portion has mesenteric attachments and is “intraperitoneal”
- Becomes “retroperitoneal”
Major landmark of internal surface of duodenum
Hepatopancreatic ampulla
Pancreas function
Secrete digestive enzymes
Gallbladder function
Secrete bile
Ligament of Treitz
- Loops over esophageal hiatus in diaphragm
- Peritoneal fold at junction of duodenum and jejunum
Jejunum
-Loops tend to be found in the LUQ
Ileum
- Loops tend to be fuond in RLQ
- Terminates at ileocecal valve
Ileocecal valve
Connection of ileum to cecum of large intestine
-Site of Vit B12 absorption
External wall of large intestine comprised of:
Taeniae coli
Haustra
Taeniae coli
3 bands of longitudinal muscle - converge at appendix
Haustra
Sacculations of the large intestine formed by contractions oft he taeniae coli
Divisions of large intestine (proximal to distal)
Appendix Cecum Ascending Transverse Descending Sigmoid Rectum
Appendix location
RLQ at McBurney’s point
McBurney’s point
Approx. halfway between ASIS and umbilicus
Cecum
Junction of ileum and large intestine separated by ileocecal valve
Ascending colon
Retroperitoneal
Transverse colon
Intraperitoneal
Descending colon
Retroperitoneal
Sigmoid colon
Intraperitoneal
Diverticula
Abnormal sacs or pouches
Diverticulitis
Inflammation or rupture (perforation) of diverticula
Primary function of sigmoid colon
Storage of feces
Spleen location and protected by?
LUQ - intraperitoneal - near tail of pancreas
lower ribs 9-12
*Difficult to palpate if WNL
If enlarged, what position can the spleen be palpated?
R lateral decubitus
Functions of spleen
Filter RBCs - removes old or abnormal
Storage of platelets
Lymphatic/immune functions
Divisions of pancreas
Head, neck, body, tail
Location of pancreas
Retroperitoneal
Crosses midline of abdomen
Head in close contact with duodenum
Tail in close contact with spleen
Ducts of the pancreas
Main pancreatic duct (Wirsung) Accessory duct (Santorini)
Main pancreatic duct
- Joins with bile duct to form hepatopancreatic ampulla
- Opens into descending duodenum via major duodenal papilla
Functions of pancreas
Endocrine - Islets of Langherhans releases hormones
Exocrine - digestive enzymes
Liver location
Intraperitoneal
RUQ and LUQ
Liver is attached in peritoneal cavity via:
Falciform ligament
Lesser omentum
Falciform ligament
Peritoneal fold attaches to anterior abdominal wall
Lesser omentum
Peritoneal fold attaches to lesser curvature of stomach
Surfaces of the liver
Diaphragmatic
Visceral
Diaphragmatic surface of liver
Dome shaped to match contour of diaphragm
*Anterior, superior, posterior portions of liver
Visceral surface of liver
Primarily posterior and inferior portions of liver
T/F: R and L portions of liver operate independently of each other
True
Cantlie’s line
- Imaginary line between gallbladder and IVC
- Marks functional divisions of liver
- Each division has its own blood supply, portal system, bile drainage system
Anatomical lobes of the liver
Left lobe
Caudate lobe
Quadrate lobe
Right lobe
Functional right lobe of liver
Anatomical right lobe
Functional left lobe of liver
Anatomical left + caudate + quadrate lobes
Functions of liver
Filter circulating toxins/drugs/hormones Active role in metabolism of macros Endocrine Activation of vit D Synth and secretion of bile
Hepatic portal system - what does “portal” mean?
Vein located between 2 capillary beds
Hepatic portal system capillary beds
GI tract and liver
How does hepatic portal system work?
- Blood travels from heart to GI tract
- O2 delivered to GI structures, nutrients picked up from GI
- Nutrients go directly to liver via portal vein
- After filtering through liver, blood leaves via hepatic veins and eventually drain into IVC
How does the liver receive oxygen?
Direct arterial supply from heart via hepatic artery
- 30% is from direct arterial supply
- 70% is via oxygen-poor blood from portal vein
What is porta hepatis?
- Exit/entrance for portal vein, hepatic ducts, hepatic artery
- Located on visceral surface of liver
What is cirrhosis?
Destruction of hepatocytes and replacement with fibrous tissue
What is portal hypertension?
Blood flow will “reverse” and flow into IVC via 3 anastomoses (gut, butt, caput)
Where are the anastomoses that reverse blood flow in portal hypertension?
- Esophagus (forms varices, can bleed)
- Rectum (forms hemorrhoids)
- Epigastric veins in anterior abdominal wall (forms “caput medusae”)
Caput medusae
Dilated superficial veins of abdomen
What is ascites?
Accumulation of fluid within peritoneal cavity due to portal hypertension
Gallbladder location
- Gallbladder fossa of visceral surface of liver
- Close proximity to proximal duodenum
Cystic duct
Leaves gallbladder to merge with common hepatic duct
Bile pathway
Gallbladder > cystic duct > common bile duct > main pancreatic duct > hepatopancreatic ampulla > main duodenal papilla
Hepatopancreatic ampulla opens into duodenum via:
Main duodenal papilla
Sphincter of bile duct is located:
Distal end of bile duct
If sphincter of bile duct is contracted:
Bile is unable to flow to small intestine and backs up into gallbladder for storage
Retroperitoneal organs
Duodenum (except proximal) Ascending, Descending colon Rectum Pancreas (except tail) Adrenal glands Kidneys Ureters Abdominal aorta and IVC
Intraperitoneal organs
Stomach Prox. duodenum Jejunum Ileum Transverse, Sigmoid colon Liver and gallbladder Tail of pancreas Spleen
Abdominal aorta branches from superior to inferior
Celiac trunk Superior mesenteric artery Renal arteries Gonadal arteries Inferior mesenteric artery Common iliac
Name branches of celiac trunk
Common hepatic artery
Splenic artery
Left gastric artery
Gonadal arteries pass through:
Inguinal canal with ductus deferens/round ligament of uterus
Common iliac arteries are ____ branches of abdominal aorta
Terminal
Common iliac arteries bifurcate at:
L4
Inferior mesenteric artery supplies:
Hindgut
Superior mesenteric artery supplies:
Midgut
Celiac trunk supplies:
Foregut