Lab 10: Abdomen Flashcards
1
Q
abdominal skeleton
A
- bounded superiorly by the abdominal diaphragm and inferiorly by the upper margin of the bony pelvis
- consists of a large cavity that is walled by muscle and serous membrane
- abdominal cavity is continuous inferiorly with the pelvic cavity which is enveloped by the bony pelvis
- structure of rib cage and tilt of pelvis cause the thoracopelvic gap between them to be higher in front than behind
- dome of abdominal diaphragm is very high -> from margins of 12th ribs up to the level of 5th ribs
- some abdominal organs are covered by the lower 5 or 6 ribs and their costal cartilage
2
Q
relationship of abdominal viscera to the rib cage
A
- several ab organs are partially, largely, or entirely covered by the rib cage
- liver- deep to rib cage, covered anteriorly by the bottom of the sternum and some of the inferior costal cartilage to the left, on the right -> covered by the 5th to 11th ribs and their costal cartilage, posteriorly it is deep to the 9th to 11th ribs
- stomach- covered anteriorly on the left side by the 5th to 8th ribs
- spleen- entirely covered by the 9th to 11th ribs
- kidneys- deep to ribs -> both adrenal (suprarenal) glands are covered by the 12th ribs
3
Q
roof of the abdominal cavity
A
- abdominal diaphragm forms the roof of the abdominal cavity
- innervated by phrenic nerve (C3-C5)
4
Q
anterolateral walls of the abdominal cavity
A
- cover by 4 muscles on each side
- one is strap-like longitudinal muscles in the front and 3 sheet-like muscles more laterally
5
Q
anterior abdomen muscle: rectus abdominis
A
- rectus abdominis- strap-like muscle that arises from the xiphoid (and 5th to 7th costal cartilage)
- runs from superior (xiphoid process), 5th-7th costal cartilages -> to the pubis
- 2 sheets
- inserts on the superior edge of the pubis
- flexes the trunk
- in between each muscle belly there is a tendinous intersections muscle section
- 3 (sometimes 4) connective tissue tendinous intersections that interrupts the muscle belly
- recuts sheath- encloses the rectus abdominis
- formed by aponeuroses of 3 lateral wall muscles
- arcuate line (bellow belly bottom)- below this line the rectus sheath is only in the front (not behind)
- semilunar line- where it stops
- tendinous sheath of lateral wall muscle - make up the layers of rectus abdominis
- innervated by spinal nerves T7-T12
6
Q
3 layers of rectus abdominis
A
external oblique aponeuroses
- internal oblique aponeuroses
- transversus abdominis
7
Q
anterolateral wall: external oblique
A
- external oblique- most superficial layer
- arises from the lower 8 ribs and the iliac crest
- fibers run inferiorly and medially and become tendinous anteriorly to form the linea alba
- inguinal ligament
- thick inferior edge of aponeurosis -> stretches between the anterior superior iliac spine and the pubic tubercle -> inguinal ligament
- superficial inguinal ring- hole in the aponeurosis above the pubic tubercle (testes exit here)
- inguinal canal passes though the inguinal ligament- testes originate here and drop)
8
Q
anterolateral wall: internal oblique
A
- middle layer
- arises from the front of the iliac crest and the inguinal ligament
- fibers run superiorly and medially -> insert onto ribs 10-12
- inferior edge form an arc above the inguinal ligament that is deep to and slightly lateral to the superficial inguinal ring
- above the umbilicus -> aponeurosis splits into superficial and deep layers around rectus abdominis
- below umbilicus -> aponeurosis runs superficial to rectus abdominis to mesh with the linea alba
- runs the opposite direction of external oblique
9
Q
anterolateral wall: transversus abdominis
A
- running horizontally
- deepest muscle layer
- arises posteriorly form an aponeurosis that passes behind quadratus lumborum
- attaches to transverse processes of L1-L5
- also attaches to the lower 6 costal cartilages -> iliac crest and inguinal ligament
- fibers run anteriorly to become aponeurotic and mesh with the linea alba
- above the umbilicus -> aponeurosis passes behind rectus abdominis
- below umbilicus -> its aponeurosis passes in front of rectus abdominis
10
Q
transversalis fascia
A
- fascial layer
- below the three layers of muscle in the anterolateral wall
- internal aspect of the abdominal wall is lined with a layer of tissue known as the transversalis fascia
11
Q
rectus sheath
A
- formed from the aponeuroses of the obliques and transversus abdominis
- arcuate line- inferior margin of posterior rectus sheath
- below arcuate line -> the rectus abdominis sits directly on transversalis fascia
- weak spot in abdominal wall
- aponeuroses of the left and right external oblique muscles cover the rectus abdominis muscles anteriorly and fuse to the midline to form the linea alba
12
Q
above arcuate line: superficial to deep
A
- external oblique aponeurosis
- first half of internal oblique aponeurosis
- rectus abdominis
- second half of internal oblique
- transversus abdominis
- transversalis fascia
- parietal peritoneum
- first and second half enclose
13
Q
below arcuate line: superficial to deep
A
- external oblique aponeurosis
- internal oblique aponeurosis
- transversus abdominis
- rectus abdominis
- transversalis fascia
- parietal peritoneum
14
Q
pyramidalis
A
- arises from the pubis and inserts into the linea alba
- 80% of people have this small muscle
15
Q
linea alba
A
- left and right muscles (anterior abdomen muscle) are separated by a longitudinal band of connective tissue called the linea alba
- tendinous intersections and linea alba create the six pack
- aponeuroses of the left and right external oblique muscles cover the rectus abdominis muscles anteriorly and fuse to the midline to form the linea alba
16
Q
posterior wall of abdomen: quadratus lumborum
A
- forms most posterior wall
- laterally flexes trunk
- forms the bulk of the posterior abdominal wall
- originates on the iliolumbar ligament and iliac crest
- inserts onto the transverse process of L1-L4 and the lowermost rib
17
Q
posterior wall of abdomen: psoas major
A
- originates on vertebral column from T12-L5
- runs down to iliacus and merges -> forms iliopsoas m.
- hip flexor, laterally flexes trunk
- forms the medial part of the posterior abdominal wall adjacent to the vertebral column
- arises from the bodies and intervertebral discs of T12-L5
- fibers merge with those of iliacus to form a conjoint iliopsoas tendon that inserts onto the lesser trochanter of the femur
18
Q
posterior wall of abdomen: psoas minor
A
- only present in 50-60% of people
- runs along the front of psoas major
- very small
- arises from the bodies and disc of T12-L1 and runs along the front of psoas major
- inserts onto the iliopubic eminence of the pelvis
19
Q
posterior wall of abdomen: abdominal diaphragm
A
- forms the superoposterior wall of the abdominal cavity
- where all the posterior abdominal wall muscles end
20
Q
peritoneum
A
- serious membrane, like pleura and pericardium
- parietal peritoneum- outer layer
- visceral peritoneum- inner layer, lies against walls of organs
- retroperitoneal organs- not enclosed by peritoneal cavity
- mesentery- reflected peritoneum that folds around an organ
- greater omentum- fat flap, double layer of visceral peritoneum (specialized mesentery)
21
Q
retroperitoneal organs
A
- suprarenal glands
- aorta/inferior vena cava
- duodenum (2nd and 3rd parts)
- pancreas
- ureter
- colon (ascending and descending)
- kidneys
- esophagus
- rectum
- SAD PUCKER
22
Q
mesenteries
A
- small intestine is suspended by the mesentery (proper)
- transverse colon suspended by the transverse mesocolon
- omentum- lesser and greater
- connects to transverse colon and hangs of the greater portion of stomach -> greater omentum
23
Q
digestive canal organs
A
- esophagus
- stomach
- small intestine
- large intestine
24
Q
accessory organs
A
- liver
- gallbladder
- pancreas
- spleen
25
Q
biliary tree
A
-carries bile and digestive enzymes from these organs to the small intestine
26
Q
stomach
A
- made up of walls of muscle layers: circular, longitudinal, oblique
- mixes food with acids to make chyme
- rugae- rough ridges for mechanical digestions
- 3 parts: fundus, body, pylorus
- 2 sphincters: cardiac and pyloric
- cardiac sphincter- between esophagus and stomach (prevents regurgitation of acid)
- pyloric sphincter- between stomach and duodenum
27
Q
stomach
A
- made up of walls of muscle layers: circular, longitudinal, oblique
- mixes food with acids to make chyme
- rugae- rough ridges for mechanical digestions
- 3 parts: fundus, body, pylorus
- 2 sphincters: cardiac and pyloric
- cardiac sphincter- between esophagus and stomach (prevents regurgitation of acid)
- pyloric sphincter- between stomach and duodenum (discharge chyme)
28
Q
stomach: mesenteries
A
- intraperitoneal
- attached to posterior
- lesser omentum- connects stomach and liver, runs in lesser curvature
- greater omentum- hangs down from the stomach, connects with transverse colon -> runs along greater curvature
29
Q
small intestine
A
- responsible for digesting food and absorbing nutrients
- 3 regions: duodenum (mainly retroperitoneal), jejunum (freely mobile, suspended by mesentery), ileum (suspended by mesentery)
- ileum opens into the cecum of the large intestine
30
Q
duodenum
A
- most proximal part of small intestine
- c-shaped
- curves around head of pancreas
- pierced by: main pancreatic duct + bile duct through major duodenal papilla
31
Q
jejunum
A
- wide lumen
- thick walls
- numerous circular folds
- superior mesenteric artery supply
- few arcades, long vasa recta
- shorter
32
Q
ileum
A
- narrower lumen
- thin walls
- fewer circular folds
- superior mesenteric artery supply
- many arcades, short vasa recta
- longer
33
Q
small intestine: mesenteries
A
- jejunum and ileum are intraperitoneal
- attached to posterior abdominal wall by mesentery
- mesentery- surrounding the blood vessels that go to the organs
- mesentery proper
- encroaches on intestinal walls in the ileum, not in the jejunum
34
Q
large intestine
A
- responsible for water absorption
- storing undigested material
- 8 regions:
- cecum
- vermiform appendix
- ascending colon
- transverse colon
- descending colon
- sigmoid colon
- rectum
- anal canal
35
Q
haustra and taeniae coli
A
- differentiates large intestine
- haustra- pouches of the large intestine
- taeniae coli- longitudinal thin muscle that goes throughout the entire large intestine
- omental (epiploic) appendages- fat blobs that hang
36
Q
large intestine: mesenteries
A
- partly intraperitoneal
- ascending and descending colon, rectum etc. are retroperitoneal
- transverse colon is intraperitoneal
- greater omentum- attaches the transverse colon to the stomach
- transverse mesocolon- attaches transverse colon to posterior abdominal wall
37
Q
liver
A
- produces bile
- filters blood from GI trace
- produces bile
- metabolizes carbs, fats, and proteins
- lobes (4)- right lobe, left lobe, quadrate lobe (next to gallbladder!), caudate lobe (next to IVC)
- round ligament of the liver (ligamentum teres)- used to be umbilical vein
- falciform ligament- separates the right and left lobe
- falciform ligament splits into 2- top portion (posterior) of the liver is bare (no peritoneum)
- hepatic portal vein, hepatic artery proper, and common bile duct (portal triad) going into the liver -> porta hepatis
38
Q
porta hepatis
A
- where blood vessels enter and exit the liver
- hepatic artery- carries oxygenated blood to tliver
- portal vein- drains blood from GI tract to liver
- common bile duct- drains bile from the liver (joins cystic duct from gallbladder to form common bile duct
- deoxygenated blood drains from the liver into the inferior vena cava
39
Q
biliary tree
A
- right + left hepatic ducts -> common hepatic ducts
- cystic duct + common hepatic duct -> common bile duct
- bile ducts and the main pancreatic duct both drain into the duodenum, via the major duodenal papilla
- bile helps break down lipids
40
Q
kidneys
A
- excrete metabolic waste
- maintain water and electrolyte balance
- blood vessels: renal arteries, renal veins
- hilum of kidneys transmit the renal artery, renal vein, and ureter
- regions: pelvis (collection chamber for urine) -> major and minor calyces; medulla (urine ducts) -> renal pyramids
- renal pyramids- receive urine form collecting ducts of the nephron
- renal papilla (opening to minor calyx)
- renal pyramids -> renal papilla -> minor calyx -> major calyx -> renal pelvis -> ureter -> bladder
41
Q
adrenal glands
A
- endocrine glands, secrete hormones including adrenaline
- blood vessels- suprarenal arteries (3) suprarenal veins
- superior suprarenal artery branches off inferior phrenic artery (which supplies the diaphragm)
- middle suprarenal artery off aorta
- inferior suprarenal artery off renal artery
42
Q
renal artery and veins relationship
A
- renal veins are superficial to renal arteries
- left renal vein is much longer than the right (bc it must cross over aorta)
- inferior mesenteric artery (IMA) comes off the aorta over the left renal vein
43
Q
nephron: tubular component
A
- glomerular (bowmans) capsule
- proximal convoluted tubule
- loop of henle
- distal convoluted tubule
- collecting duct
- urine leaves through collecting duct
- things that are moved into the blood leave through efferent arteriole
44
Q
nephron: vascular component
A
- afferent arteriole
- glomerulus
- efferent arteriole
- peritubular capillary network
45
Q
arteries of abdomen
A
- 3 major branches of abdominal aorta:
- celiac trunk (T12-L1)- emerges near aortic hiatus -> supplies foregut
- superior mesenteric artery (L1)- supplies midgut
- inferior mesenteric artery (L3)- supplies hindgut (splenic flexure, ascending and descending colon, rectum)
- also note that paired visceral branches from the aorta: middle suprarenal arteries, renal arteries, gonadal arteries
46
Q
celiac trunk
A
- main branches:
1. left gastric artery: supplies stomach, esophagus
2. splenic artery: supplies pancreas spleen (gives off left gastroepiploic artery)
3. common hepatic artery: splits into gastroduodenal artery and proper hepatic artery - gastroduodenal artery- supplies duodenum (gives off right gastroepiploic artery)
- proper hepatic artery- supplies liver (gives off right gastric artery to stomach and cystic artery to gallbladder)
47
Q
anastomoses
A
- 2 different sources of blood join and form one artery
- lesser curvature gets blood from left gastric artery and right gastric artery -> they combine
- left side
48
Q
superior mesenteric artery
A
-L1
-enters mesentery of small intestine
-supplies distal 1/3 of duodenum, remaining small intestine, proximal large intestine
1. jejunal branches
2. ileal branches
3. middle colic artery: gives blood to transverse colon and some ascending colon,
4.
49
Q
inferior mesenteric artery
A
- supplies distal large intestine and proximal rectum
- branches:
1. left colic artery- supplies distal transverse colon and proximal descending colon
2. sigmoid branches- supply descending colon, sigmoid colon
3. superior rectal artery-
50
Q
venous drainage
A
- systemic venous system drains blood from the whole body (except the GI tract)
- portal venous system drains blood from the GI tract
- passes through liver before continuing to the heart
51
Q
portal venous system
A
- inferior mesenteric vein drains into splenic vein
- splenic vein meets up with superior mesenteric vein -> forms hepatic portal vein
- portal vein enter the liver via the porta hepatis
52
Q
gonadal vessels
A
- gonadal arteries- testicular artery in males and ovarian artery in females
- gonadal veins are not symmetrical
- left gonadal vein drains into left renal vein
- right gonadal veins drains into inferior vena cava
53
Q
peritoneum
A
- cavity that is enclosed by the abdomen and pelvis is lined with a serous membrane -> peritoneum
- peritoneal sac has an outer parietal and inner visceral component that lies against the walls of organs that have pushed into it
54
Q
peritoneal cavity
A
-membranous sac that some of the abdominal organs protrude
55
Q
retroperitoneal
A
- sit between the parietal peritoneum and the posterior wall of the abdomen
- kidneys and adrenal glands, ascending colon, descending colon, rectum, parts of the pancreas and duodenum
56
Q
mesentery
A
-push into the peritoneal sac from behind
-push into the sac so deeply that the peritoneum stretches out behind them becoming bilaminar between the organ and the posterior abdominal wall
-permits the organ a degree of movement and it is the conduit for blood vessels and nerves to the organ
-small intestine is suspended by the mesentery -> mesentery proper
-transverse colon is suspended by a mesentery -> transverse mesocolon
-
57
Q
omentum or ligament
A
- some organs push into the peritoneal sac even more deeply
- one organ may push into the sac in front of another, so the first becomes suspended by a bilaminar sheet of peritoneum that is reflected off of the second
- suspensory fold such as this is referred to as either a ligament or omentum
58
Q
lesser omentum
A
-stomach is suspended from the liver
59
Q
greater omentum
A
- stomach and transverse colon are connected by a large flap of peritoneum known as greater omenutm
- hangs down like an apron to cover the front of most of the intestinal tract
- it will adhere to the surface of the gut around a site of infection or perforation which helps seal off and localize such conditions
60
Q
digestive system
A
- consists of alimentary canal and the abdominal organs of digestion that are associated with it
- alimentary canal begins with the oral cavity and includes the oropharynx and pharynx in the head and beck and the esophagus through the neck and thorax
- esophagus passes through the abdominal diaphragm to enter the gut
- gut is contained with the abdominopelvic cavity
- about 1/2 inch below the diaphragm the esophagus opens into the stomach
- stomach leads to small intestine (21 ft)
- small intestine opens into the large intestine (4ft)
- digestive organs associated with alimentary -> liver, gall bladder, pancreas
61
Q
small intestine
A
- duodenum
- jejunum
- ileum
- most of the digestion of food and the absorption of nutrients
- 2 layers of smooth muscle: longitudinal and circular (superficial to deep)
- longitudinal- peristaltic
- circular- segmenting contractions
62
Q
large intestine
A
- cecum
- vermiform appendix
- ascending colon
- transverse colon
- descending colon
- sigmoid colon
- rectum
- anal canal[
- absorption of water and storage of undigested material until it can be expelled as feces
- 4 ft
- shorter but larger diameter than small intestine
- forms frame around small intestine
63
Q
spleen
A
- lymphatic organ primarily
- produces a substance used by the liver to make bile which is digestive
64
Q
bile
A
- liver produces and gallbladder stores bile
- delivered into the small intestine by a network of tubes -> biliary tree
- biliary tree opens into the duodenum
- liver also filters blood from the intestines and metabolizes the carbohydrates, fats, and proteins that are carried to it by that blood
65
Q
pancreas
A
- produces the hormone insulin -> key role in carbohydrate metabolism
- most of substance manufactures digestive enzymes
- delivered to the small intestine by tubes that are linked to the biliary tree
66
Q
gut
A
- foregut
- midgut
- hindgut
- receive blood from separate vessels form the abdominal aorta -> celiac, superior mesenteric, inferior mesenteric
67
Q
portal venous system
A
- blood from the GI has to be filtered by the liver before it reaches the heart
- carries blood from the gut to the liver
68
Q
stomach
A
- large, dilated portion of the alimentary canal
- stores food for processing and mixes the foot with acidic secretion from glands in its walls to form semifluid -> chyme
- delivers chyme to the small intestine
- esophagus is continuous with the stomach just below the abdominal diaphragm
- opening into the stomach is known as the cardiac orifice
- greater curvature- longer left margin
- lesser curvature- shorter right margin
- 3 parts: fundus, body pylorus
- fundus- dome-shaped region that extends upward from the cardiac orifice
- body- extends from the level of the cardiac orifice to the end of the lesser curvature
- pylorus- extends to the point at which the stomach becomes continuous with the small intestine
69
Q
cardiac sphincter
A
-circular band of smooth muscle that surrounds the cardiac orifice prevents the regurgitation of food and drink
70
Q
pyloric orifice
A
- stomach opens into the small intestine at the pyloric orifice
- walls of this orifice are thickly muscles forming the pyloric sphincter -> regulates the discharge of chyme into the small intestine
71
Q
stomach wall
A
- mucous membrane that lines the inside of the stomach wall is thick
- numerous folds -> rugae
- rugae- mainly longitudinal oriented, flatten out as the stomach become distended with food
- stomach can expand to accommodate a bit more than a quart of ingested material
- walls of stomach comprise of three layers of smooth muscle: longitudinal, circular, oblique (superficial to deep)
72
Q
duodenum
A
- retroperitoneal- fixed in place
- C-shaped
- curves around the head of the pancreas
- continuous with the second part of the small intestine -> jejunum
- vertical portion is pierced by the conjoined main pancreatic duct and bile duct -> forms the major duodenal (hepatopancreatic) papilla
- the orifice of this small projection on the inner surface is guarded by a smooth muscle sphincter -> sphincter of oddi
- accessory pancreatic duct- opens a little proximal sphincter of oddi it through minor duodenal (hepatopancreatic) papilla
- muscous membrane lining the inside has numerous transverse permanents fold -> plicae circulares -> serve to increase SA for absorption
73
Q
jejunum
A
- long coils- freely movable
- attached to the posterior abdominal wall by a fold of the peritoneum -> mesentery
- lies primarily in the upper left of the peritoneal cavity
- wide lumen and thick wall
- supplied by the superior mesenteric artery -> branches of which form anastomosing arcades
- branches form only one or two arcades and heir terminal portions are long
- numerous closely set plicae circulares
- shorter than ileum -> 7 1/2 ft
74
Q
ileum
A
- lies mostly in the lower right part of abdomen
- opens into the cecum of the large intestine
- long coils- freely movable
- attached to the posterior abdominal wall by a fold of the peritoneum -> mesentery
- narrow lumen and thin wall
- supplied by the superior mesenteric artery -> branches of which form anastomosing arcades
- branches form several arcades and their terminal portions are short
- plicae are set farther apart in the proximal part and are absent from its distal part
- 11 ft
75
Q
cecum
A
- forms a pouch below its junction with the ileum at the ileocecal orifice
- orifice is guarded by the ileocecal valve
- hanging from the end of the cecum is the vermiform appendix -> opens into the cecum alittle below the ileocecal orifice
- base of appendix lies directly behind a point on the anterior abdominal wall (McBurney’s point) -> 1/3rd of the way up a line drawn between the right anterior superior iliac spine and the umbilicus
76
Q
ascending colon
A
- extends up the right side of the abdomen form the cecum to the liver
- turns to the left at the right colic (hepatic) flexure
- at this flexure the ascending colon becomes the transverse colon
- transverse colon hangs down a bit as it crosses the abdomen to a point just below the spleen
- turns downward at the left colic (splenic) flexure -> becomes the descending colon
77
Q
descending colon
A
- runs downward along the left side of the abdomen to become the sigmoid colon at the brim of the pelvis
- sigmoid colon leads to the rectum
78
Q
rectum
A
- beings at the level of the 3rd sacral vertebra (S3)
- runs downward along the sacrum to the level of the top of the coccyx
- pierces the pelvic diaphragm to become the anal canal
79
Q
taeniae coli
A
- longitudinal layer of muscle that completely surround the outside of the small intestine is retricted to 3 separate band in the large intestine -> taeniae coli
- they cause regular bulges and constrictions along most of the large intestine
- bulges-> haustra
- haustra can be visualized by x-rays when the colon is coated internally with radiopaque material such as barium
- taeniae coli and haustra extend the entire length of the colon up to the rectum -> rectum and anal canal lack
- circular muscle fibers of the anal canal form an anal sphincter which is aided by a ring of skeletal muscle around it
- anal canal opens at the anus
80
Q
liver
A
- digestive- filters blood from the GI, metabolizes carbs, fats, and proteins carried by the blood -> produces bile
- pyramidal shape
- covered by rib cage
- convex upper (diaphragmatic) surface is molded to the inferior surface of the abdominal diaphragm
- inferior (visceral) surface is slightly concave
- surface are separated in form by the sharp inferior border
- 4 lobes: right (large), left (smaller), quadrate, caudate
- quadrate and caudate lobes are central placed on the visceral surface -> left side of the liver
- left and right lobe are separated by the mesentery that attached the liver to the middle of the anterior abdominal wall -> falciform ligament
- falciform ligament is a thickened inferior free edge of ligamentum teres
- ligamentum teres- extends from the liver to the umbilicus -> remnant of the fetal umbilical vein
- peritoneum reflect off the livers visceral surface between the quadrate and caudate lobes as the lesser omentum
- liver is covered with peritoneum except for the bare area of the diaphragmatic surface around the inferior vena cava
81
Q
gallbladder
A
- peeks out from the visceral surface of liver under the inferior border at a point just behind the tip of the 9th costal cartilage
- pear shaped sac
- 3 parts: fundus, body, neck
- fundus- rounded end that projects below the inferior margin of the liver
- body- lies against the visceral surface of liver
- neck- extends from the body to a tube known as the cystic duct
- tubes that carry bile connect the liver to the gallbladder and connect the liver and gallbladder to the duodenum -> tubes comprise the biliary tree
- left and right hepatic duct- drain bile from the left and right lobes of the liver
- left and right hepatic duct joint -> form common hepatic duct -> exits the liver through the porta hepatis
- common hepatic duct is joined by the cystic duct from the gallbladder -> forms bile duct
- bile duct runs inferiorly and joins main pancreatic duct from the pancreas just before opening into the duodenum of the small intestine -> these 2 ducts enter the duodenum through hepatopancreatic orifice (ampulla) that is guarded y the sphincter of oddi
82
Q
porta hepatis
A
- place through which the blood vessels and ducts enter and exit the liver
- hepatic artery- supplies the liver with oxygenated blood
- portal vein- drains blood from the entire GI tract to the liver
- common hepatic duct- drains bile from the liver
83
Q
inferior vena cava
A
-deoxygenated filtered blood is drained from the liver into the inferior vena cava by 2 very short hepatic veins that emerge from its posterior surface
84
Q
pancreas
A
- transverse the posterior abdominal wall behind the stomach at the level of L2-L3
- extends from the vertical part of the duodenum to the spleen
- retroperitoneal
- 4 parts: heads, neck. body, tail
- head- fits into the C shape bend of the duodenum
- neck- connects the head to the body
- tail- contacts the spleen
- digestive enzymes are drained from the pancreas by the main pancreatic duct -> runs the length of the organ
- joins with the bile duct to open into the duodenum at the hepatopancreatic orifice or major duodenal papilla
- main pancreatic duct has a branch in the head of the pancreas known as the accessory pancreatic duct
- opens into the duodenum a little proximal to the hepatopancreatic orifice through the minor duodenal papilla
85
Q
blood vessels of the gut
A
- alimentary and associated digestive organs are supplied by 3 arteries that arise from the front of the abdominal aorta
- venous blood from the gut contain products absorbed from digested food, so it must be processes by the liver before it can be added to the general circulatory system
- blood is taken to the liver by the portal venous system -> bypasses the inferior vena cava
- after filtering and processing it -> liver returns the blood to the inferior vena cava for general circulation
86
Q
foregut: blood supply
A
- gives rise to the esophagus stomach and duodenum
- also contains the liver, gallbladder, pancreas, and spleen
- celiac artery (trunk) serves the foregut
87
Q
midgut: blood supply
A
- gives rise to the rest of the small intestine, the cecum, and the vermiform appendix as well as the ascending colon and most of the transverse colon
- supplied by the superior mesenteric artery
88
Q
hindgut: blood supply
A
- gives rise to the terminal portion of the transverse colon together with the descending colon, sigmoid colon, rectum and anal canal
- supplied by the inferior mesenteric artery
89
Q
abdominal aorta
A
- aorta enters the abdominal cavity through the aortic hiatus at the back of the abdominal diaphragm
- aorta enters the abdominal cavity at the level of T12 and runs along the front of the vertebral column -> bifurcates at the level of L4 into the left and right common iliac arteries
- between the common iliac arteries is the thin terminal branch of the aorta known as the median sacral artery -> runs across L5 and the front of the sacrum
- abdominal aorta gives off 3 large, unpaired median branches to abdominal (and pelvic) viscera and 3 paired lateral branches to abdominal (and pelvic) viscera
- abdominal aorta also gives off 5 paired lateral branches to the muscles of the abdominal wall
- uppermost of these 5 is the inferior phrenic artery -> supplies the abdominal diaphragm
- other 4 are known as lumbar arteries -> run across the bodies of the lumbar vertebrae
90
Q
unpaired median visceral branches
A
- celiac artery (trunk)
- superior mesenteric artery
- inferior mesenteric artery
91
Q
celiac artery branch
A
- first branch to arise from the abdominal aorta, soon after it emerges through the diaphragmatic hiatus
- comes off at the level of T12-L1
92
Q
superior mesenteric artery
A
- arises from the abdominal aorta immediately below the celiac artery
- comes off at the level of L1
93
Q
inferior mesenteric artery
A
-somewhat lower, arising from the front of the abdominal aorta at the level of L3
94
Q
paired lateral visceral branches
A
- middle suprarenal arteries
- renal arteries
- gonadal arteries
- gonadal arteries: ovarian arteries and testicular arteries
95
Q
middle suprarenal arteries
A
- left and right middle suprarenal arteries arise from the sides of the abdominal aorta at about the same level as the superior mesenteric artery
- supply the suprarenal (adrenal) glands with blood
- each gland receives blood from 3 arteries
- superior suprarenal arteries is a branch of the inferior phrenic artery, and the inferior suprarenal artery is a branch of the renal artery
96
Q
renal arteries
A
- left and right renal arteries arise from the sides of the abdominal aorta just below the level of the superior mesenteric artery
- supply the kidneys with blood
97
Q
gonadal arteries
A
- left and right gonadal arteries arise from the sides of the abdominal aorta just below the level of the renal artery
- supply the gonads with blood
- depending upon the sex the gonadal arteries are properly referred to as either ovarian or testicular arteries
- gonadal arteries arise at this level bc embryologically the gonads begin to develop high in the abdominal cavity
- descend along the back wall of the abdominal cavity during prenatal development to reach their final positions in the 4th month (ovaries) or just before birth (testes)
98
Q
celiac artery
A
- very short
- arises from the aorta just below the abdominal diaphragm and behind the head of the pancreas
- divides into 3 branches: left gastric artery, splenic artery, common hepatic artery
99
Q
celiac artery: left gastric artery
A
- branch of celiac artery
- ascends towards the junction of the stomach and esophagus -> supplying each
100
Q
celiac artery: splenic artery
A
- branch of celiac artery
- runs to the left along the top of the pancreas into the spleen, supplying both
- just before entering the spleen, it gives off the left gastroepiploic (gastro-omental) artery
- runs back to the right along the greater curvature of the stomach
101
Q
celiac artery: common hepatic artery
A
- branch of celiac artery
- runs to the right toward the liver
- divides into the hepatic artery (proper) and the gastroduodenal artery
- after the gastroduodenal artery comes off -> there are 2 other branches from the hepatic artery -> right gastric and the cystic artery
- gastroduodenal artery- comes off behind the duodenum and supplies it -> gives off a branch -> right gastroepiploic artery
- gastroepiploic artery- which runs to the left along the greater curvature of the stomach to anastomose with the left gastroepiploic artery
- right gastric artery- comes off the hepatic artery and runs to the left and upward along the lesser curvature of the stomach to anastomose with the left gastric artery
- cystic artery- arises from the hepatic artery just before the porta hepatis of the liver to supply the gallbladder
102
Q
superior mesenteric artery
A
- arises from the aorta just below the celiac artery
- runs between the pancreas and the top of the horizontal part of the duodenum
- enter the mesentery of the small intestine
- supplies the distal third of the duodenum, the entire intestine, and the proximal part of the large intestine
- as it runs through the mesentery it gives of 12 to 15 branches to the jejunum and ileum
- jejunal branches form one 1 or 2 anastomosing arcades and their terminal portions are long
- ileal branches by comparison have several arcades and their terminal portions are short
- the superior mesenteric artery supplies the proximal half of the large intestine by 3 large branches: middle colic, right colic, and ileocolic
- middle colic artery- first to arise and supplies the terminal portion of the ascending colon and most of the transverse colon
- right colic artery- second to arise and supplies most of the ascending colon
- ileocolic artery- last to arise and supplies the cecum and appendix
103
Q
inferior mesenteric artery
A
- arises at the level of L3 (about 1 1/2 inches above the bifurcation of the aorta into the left and right common iliac arteries)
- has a smaller diameter than diameter than either the celiac artery or the superior mesenteric artery
- supplies the distal part of the large intestine and the proximal part of the rectum
- gives off the left colic artery -> supplies the end of the transverse colon and beginning of the descending colon
- gives off several sigmoid branches -> supply the descending colon and sigmoid colon
- terminal portion of the inferior mesenteric artery changes its name to the superior rectal artery as it crosses over the left common iliac artery
- superior rectal artery supplies the proximal third of the rectum
104
Q
venous drainage
A
-nutrient rich blood from the GI is transported to the liver for filtration and processing by a network of veins that comprise the hepatic portal venous system
-portal venous system is defined as originating in 1 capillary bed and terminating in a 2nd capillary bed
-hepatic portal system originates in the capillaries of the GI and terminates in the capillaries of the liver
-veins that drain blood from the digestive organs merge to form the short (Hepatic) portal vein -> enters the liver
-veins that drain blood from the digestive organs have the same names as the arteries they feed from (spleen is supplied by the splenic artery and drained by splenic vein)
-distal parts of the veins also follow the paths taken by the arteries of the same name
-more proximal portions of the veins have somewhat different courses
-(hepatic) portal vein is formed behind the pancreas by the union of the splenic vein and the superior mesenteric vein
-
105
Q
superior mesenteric vein
A
- drains the small intestine, cecum, ascending colon, and transverse colon
- it is fed by about a dozen jejunal and ileal veins and by 3 large tributaries: middle colic vein, the right colic vein, and the ileocolic vein
- superior mesenteric vein also receives blood from the pancreaticoduodenal vein and gastroepiploic vein -> drains the duodenum and greater curvature of the stomach
106
Q
splenic vein
A
-drains the spleen and has a large tributaries: inferior mesenteric vein
107
Q
inferior mesenteric vein
A
- drains the descending colon, sigmoid colon, and the proximal third of the rectum
- fed by 3 principal tributaries: left colic vein, sigmoid veins, and the superior rectal vein
108
Q
(hepatic) portal vein
A
- formed by the union of the superior mesenteric and splenic veins
- 3 veins drain into it: left gastric vein and right gastric vein, and cystic vein
- left gastric and right gastric veins drain the lesser curvature of the stomach
- cystic vein drains the bladder
- portal vein enters the liver via the porta hepatis and then splits into the left and right branches that take blood to the livers lobules
- blood that is filtered through the lobules is collected by numerous central veins that merge to form the 2 hepatic veins
- hepatic veins drain directly into the inferior vena cava
109
Q
lymphatic draingage
A
- abdomen, pelvis, and lower limbs are drained of lymph by 2 sets of trunks that run along the posterior abdominal wall
- trunks merge to form the thoracic duct
- largest lymphatic structure in the body is the spleen
- lymph from the anterior abdominal wall and lower limbs drain into very large inguinal nodes that lie in the femoral triangle just below the inguinal ligament -> these nodes are easily palpated even in the absence of infection
- lymph ducts from retroperitoneal abdominal organs (e.i. kidneys) drain into nodes that lie along either side of the abdominal aorta -> these lumbar nodes are connected by large ducts known as lumbar trunks
- gut is drained by ducts that follow one of the 3 arteries that arise from the front of the abdominal aorta to supply it -> these ducts lead to preaortic nodes that lie along the front of the aorta -> connected by a large duct known as the intestinal trunk
- lumbar and intestinal trunks merge at the level of L1-L2 to form the thoracic duct which is dilated here as the cisterna chyli
- thoracic duct ascends through the thorax to empty into the left brachiocephalic vein
- spleen is the principal lymphatic organ -> composed mainly of lymphatic tissue that filters blood passing through it
- spleen also involves production of bilirubin, a constituent of bile
- transported to the liver by the splenic and hepatic portal veins
110
Q
spleen
A
- lies behind and to the left to the stomach between the 9th and 11th ribs
- resides above the left colic flexure and anterior to the left kidney
- blood and lymph vessels enter its concave visceral surface via the hilum
- spleen receives blood from the splenic artery (primary branch of the celiac artery)
- blood from the spleen is drained by the splenic vein
- splenic vein is joined by the inferior mesenteric vein to drain into the hepatic portal vein
111
Q
kidney and adrenal glands
A
- kidneys excrete most of the bodies metabolic waste product and help maintain water and electrolyte balance
- waste and products leave the kidney as urine which passes down down a muscular tube, the ureter, to the bladder
- lying on the superior pole of each kidney is an adrenal (suprarenal) gland
- each gland consists of 2 separate masses of tissue: the cortex secretes over 20 steroid hormones
- medulla secretes amine hormones
- kidneys and adrenal glands are retroperitoneal
- each kidney is covered with 4 protective layers of tissue: fibrous capsule, a layer of perirenal fat, renal fascia, and layer of pararenal fat (superficial to deep)
- medial, concave aspect of the kidney has a vertical slit called the hilum
- transmits the renal artery, the renal vein, the renal pelvis, and autonomic nerve fibers
112
Q
arteries of the kidneys
A
- each kidney is supplied by a renal artery
- arise from the left and right sides of the abdominal aorta a bit below the origin of the superior mesenteric artery
- right renal artery passes behind the inferior vena cava
113
Q
arteries of the adrenal glands
A
- adrenal glands are richly supplied with blood by 3 arteries
- first is the superior suprarenal artery
- its is a branch of the inferior phrenic artery, which arises from either side of the aorta immediately below the diaphragm
- second artery is the middle suprarenal artery - arises from either side of the aorta just below the level of the celiac artery
- third artery is the inferior suprarenal artery- runs upward to the gland from the renal artery
114
Q
veins of the kidneys
A
- each kidney is drained by a renal vein
- these empty into the inferior vena cava
- left renal vein crosses anterior to the aorta just below the root of the superior mesenteric artery
- because the left renal vein has to cross the aorta to reach the kidney, it is longer than the right renal vein
115
Q
veins of the adrenal glands
A
- each adrenal gland is drained by the suprarenal vein
- on the right it enters the inferior vena cava directly
- on the left, it enters the left renal vein
116
Q
structure of the kidney
A
- the medial, concave aspect of the kidney has a vertical slit called the hilum
- transmits the renal artery, renal vein, and renal pelvis
- the renal pelvis is the enlarged beginning of the ureter
- hilum extends into the substance of the kidney for a short distance, creating the renal sinus
- longitudinal section through the kidney reveals that it is composed of 3 distinct regions around the renal sinus
- first region comprises the collection chambers for urine
- renal pelvis branches into several chambers called major calyces
- each major calyx branches into several smaller, funnel-shaped chambers known as minor calyces
- there are about a dozen minor calyces
- urine drains from the renal pyramids into the minor calyces
- renal medulla is composed of about a dozen renal pyramids
- each pyramid is cone shaped structure that contains numerous straight urine collecting ducts
- the ducts open at the apex, or papilla, of the renal pyramid into the minor calyx
- renal cortex contains numerous twisted (convoluted) tubes and capillaries and the renal corpuscles
- between adjacent renal pyramids is a pillar of tissue that descends from the renal cortex
- this pillar is called the renal column -> contains arteries and veins
- renal pyramid together with the renal cortex capping it constitutes a renal lobe
- nephrons are contained within the renal lobes
- nephrons are the functional units of the kidneys
- they are responsible for the production of urine
117
Q
nephron
A
- functional unit of the kidney
- each nephron lies within the renal medulla, and part lies within the adjacent renal cortex
- most of the nephron is located within the renal cortex above a renal pyramid
- produces urine by a 2 stage filtration process
- blood plasma filters from a capillary bed into the end of a tube that ultimately drains into a minor calyx
- it is desirable to conserve water, salt, and sugar -> reabsorbed back into blood vessels from the tube
- excreted urine is hyperosmotic and largely devoid of salt and sugar
- each nephron has a tubular component and a vascular component
118
Q
tubular component of the nephron
A
- comprised of a renal tubule that is closed at one end and open at the other
- closed beginning of the tubule has a cup-shaped expansion known as the glomerular (bowmans) capsule
- surrounds a tightly twisted capillary bed, known as the glomerulus
- together glomerular capsule constitute the renal corpuscle
- short distance from the glomerular capsule, the renal tubule becomes twisted as the proximal convoluted tubule
- then straightens out and loops into and out of the renal pyramid as the loop of henle
- loop of henle is also known as the nephron loop
- limbs of the loop of henle descend into and ascend from the renal pyramid
- after ascending the tubule becomes twisted again as the distal convoluted tubule
- a short distance from the glomerular capsule, the renal tubule becomes surrounded by a second capillary network
- renal tubule opens into a collecting duct which drains several nephrons
- collecting duct opens at the papillae of the renal pyramid into the minor calyx
119
Q
vascular component of the nephron
A
- consists of 2 capillary networks connected by an arteriole -> portal system
- first capillary bed is the glomerulus
- blood reaches the glomerulus through a small vessel called an afferent arteriole
- about 20% of the blood plasma moving through the afferent arteriole filters through the glomerulus
- blood that passes through the glomerulus leaves it by another small vessel called an efferent arteriole
- this leads to the 2nd capillary network, where reabsorption of water, salt, and sugar takes place
- 2nd network is intertwined around the renal tubule -> peritubular capillary
- small vessels lead from the peritubular capillary to the renal vein
120
Q
gonadal blood vessels
A
- gonads are within or below the pelvis
- their vasculature originates high up in the abdomen
- vessels that supply and drain their blood are the same, whether the gonads are ovaries or testicles
121
Q
gonadal arteries
A
- left and right gonadal arteries arise from the front of the abdominal aorta just below the level at which the renal arteries come off
- gonadal arteries descend to the left and right to supply the respective gonad
122
Q
gonadal veins
A
- right gonadal vein follows the course of the right gonadal artery for much of its length
- enters the front of the inferior vena cava just below the level at which the renal veins come off
- left gonadal vein follows the course of the left gonadal artery for much of its length, but as it approaches the kidney, it departs company from the artery
- runs straight upward to drain into the left renal vein
123
Q
nerves in the abdomen
A
- skeletal muscles of the abdomen are supplied by spinal nerves
- spinal nerves that emanate from the spinal cord in the abdomen also innervate muscles of the lower limb
- GI tract and organs of digestion, as well as the spleen, kidneys, and adrenal glands, are supplied by autonomic nerves
124
Q
spinal nerves in the abdomen
A
- skeletal muscles of the abdominal wall are supplied by spinal nerves T7-L1
- muscles of the lower limb are innervated by the ventral rami of L1-L4, which form the lumbar plexus
- lowermost lumbar spinal nerve (L5) contributes to the sacral plexus
- these plexuses are connected by the lumbosacral trunk between L4 and L5
125
Q
cranial nerve in the abdomen
A
- vagus nerve (CN X) is the only cranial nerve to enter the abdominal cavity
- recall that the left vagus nerve enters the abdomen in front of the esophagus as the anterior vagal trunk
- it gives branches to the liver, gallbladder, stomach, and duodenum and to the kidneys and adrenal glands
- right vagus enters the abdomen behind the esophagus as the posterior vagal trunk
- its fibers are distributed with the branches of the celiac and superior mesenteric arteries
- innervates the pancreas, the spleen, the stomach, the small intestine, and the large intestine as far as the left colic (splenic) flexure
126
Q
sympathetic chain in the abdomen
A
- sympathetic chain also runs through the abdomen into the pelvis
- only spinal nerves L1-L2 contribute preganglionic fivers to the chain
- sympathetic ganglia below L2 have gray rami communicantes, but no white ones
- sympathetic chain below L2 is similar to the sympathetic chain in the neck
