B5.011 GI Organs and the Retroperitoneum Flashcards
1
Q
GI tract
A
mouth > pharynx > esophagus > stomach > duodenum > jejunum > ileum > large intestine (cecum) > ascending colon > transverse colon > descending colon > sigmoid colon > rectum > anal canal
2
Q
GI associated organs
A
liver gallbladder pancreas spleen kidneys adrenal glands
3
Q
foregut
A
proximal to 2nd half of duodenum
celiac axis blood supply
epigastric innervation
4
Q
midgut
A
distal half of duodenum to proximal 2/3 of transverse colon
superior mesenteric artery blood supply
paraumbilical innervation
5
Q
hindgut
A
distal 1/3 of transverse colon to rectum
inferior mesenteric artery blood supply
suprapubic innervation
6
Q
vessels off of celiac trunk
A
left gastric artery
splenic artery
common hepatic artery
7
Q
vessels off of SMA
A
ileocolic artery
right colic artery
middle colic artery
8
Q
vessels off of IMA
A
left colic artery
sigmoidal arteries
superior rectal artery
9
Q
spleen overview
A
oval shaped, fist sized, but variable
protected by lower left thoracic cage, normally not palpable
largest lymphatic organ
removes old RBCs
10
Q
splenic anatomy
A
4 borders (anterior, superior, posterior, inferior)
4 surfaces (diaphragmatic, gastric, colic, renal)
intraperitoneal, expandable, mobile
one hilum
one fibrous capsule
11
Q
splenic hilum
A
includes gastrosplenic ligament (contain short gastric vessels)
splenorenal ligament
12
Q
relationship of spleen to other organs
A
anterior- stomach
posterior, superior, lateral- diaphragm
inferior- left colic flexure and left kidney
medial- left kidney, left adrenal gland, tail of the pancreas
13
Q
splenic vessels
A
splenic artery- from celiac trunk artery, highly coiled, superior and posterior to pancreas body
splenic vein- drains to hepatic portal vein
14
Q
splenic rupture
A
most frequent injured organ in the abdomen
caused by sudden deceleration
can lead to hypovolemic shock if massive
hard to repair, usually splenectomy is performed
15
Q
Kehrs sign
A
pain from splenic rupture irritating the undersurface of the diaphragm on the left side
sharp pain in the left shoulder
16
Q
splenomegaly
A
abnormally enlarged, palpable under left costal arch
common causes include congestion due to portal hypertension, infiltration by leukemias and lymphomas, mono (EBV)
17
Q
“local” spleen pain
A
blood leaks and irritates parietal peritoneal wall adjacent to spleen
18
Q
what is the pancreas
A
an enlongated digestive and endocrine gland, located retroperitoneal wrapped by the duodenum and extending towards the spleen
19
Q
5 parts of the pancreas
A
head- within C shaped duodenum (to the right of SMA and SMV)
uncinated- process posterior to SMA and SMV
neck- short region anterior/ overlies SMA and SMV
body- left of neck @ L1/L2
tail- touches splenic hilum
20
Q
pancreatic duct
A
runs along the body, joins common bile duct to form hepatopancreatic ampulla (space that allows the mixing of bile and pancreatic secretions)
opens into duodenum at major duodenal papilla, projects into the lumen of the 2nd portion of the duodenum
21
Q
sphincters of hepatopancreatic ampulla
A
sphincter of common bile duct
sphincter of pancreatic duct
sphincter of hepatopancreatic ampulla (Oddi)
22
Q
pancreatic arteries
A
- splenic
- gastroduodenal
- SMA
23
Q
pancreatic veins
A
- splenic
2. SMV
24
Q
blockage of sphincter of oddi
A
can cause pancreatitis
gallstone blocks the ampulla, causes bile flow into the pancreas
incompetent sphincter of Oddi
spasm of sphincter of Oddi
25
pancreatic cancer
cancers in the head region may cause jaundice
neck and body cancers may cause obstruction of portal vein or IVC
typically present as epigastric pain or severe back pain
typically metastasizes to liver
26
pancreatic cancer epidemiology
median survival time 6-12 months, 5% survival rate
| 4th most common cancer death in US
27
pancreas referred pain
small tumor- jaundice, no pain
large tumor- jaundice and pain
pain comes first and then jaundice typically
innervation- great thoracic splanchnic nerve T5-9
28
liver overview
```
largest internal organ
weighs 1500 g
accepts absorbed nutrients from GI tract via portal vein
stores glycogen
produces bile
```
29
liver positioning in abdomen
RUQ and some LUQ
R. hypochondriac and epigastric regions
R. thoracic cage
anteriorly from 5th rib (nipple) to costal arch
posteriorly from 9th to 12th ribs
should not extend below right costal margin
30
diaphragmatic surface of liver
```
anterior, superior, posterior
dome shaped
has bare area
covered by visceral peritoneum, continues with parietal peritoneum and forms
-coronary ligament
-right triangular ligament
-left triangular ligament
-falciform ligament
```
31
what is the subphrenic recess of the liver
between diaphragm and diaphragmatic surface of the liver
fluid flow to subhepatic space
falciform ligament splits subphrenic recess into L and R
32
hepatorenal recess
pouch of Morison
ultrasound used in ED to detect blood accumulation when GI bleeding is suspected
most dependent spot when laying supin
33
subphrenic abscesses
often happen on R side from duodenal ulcers or appendicitis
| can be drained below or at 12th rib or right costal margin
34
visceral surface of liver
2 sagittal fissures on each side of porta hepatis
- right sagittal fissure- from fossa of gallbladder to prove of IVC
- left sagittal fissure- from ligamentum teres to ligamentum venosum
35
porta hepatis
transverse fissure on visceral surface where the following structures enter or leave the liver:
- portal vein
- hepatic artery
- common bile ducts
36
portal triad
portal vein, hepatic artery, and common bile duct travel together in the hepatoduodenal ligament
37
anatomical lobes of the liver
falciform ligament and left sagittal fissue divides left and right anatomical lobes
porta hepatis divides quadrate (inferior) and caudate lobes (superior)
38
causes of hepatomegaly
accumulation of blood- CHF
inflammation
tumor
chronic ethanol consumption
39
result of hepatomegaly
pain in right hypochondriac region, liver can be palpated below right costal margin, jaundice, liver function abnormality
40
hepatic cirrhosis
liver parenchyma is replaced by fat and fibrous tissue
caused by alcoholism, drug or chemical toxification, hepatitis
results in portal hypertension
41
gallstones
composed of cholesterol crystals, may be in gallbladder, cystic duct, or common bile duct
more common in females, increase with age
can be symptom free
42
biliary colic
stone lodged in cystic duct causing intense, spasmodic pain
43
cholecystitis
inflammation of gallbladder due to bile accumulation
gallbladder enlargement, epigastric or right hypochondriac region pain
"murphys sign" jaundice
44
murphys sign
1. ask patient to exhale
2. place hand below costal margin on right side
3. patient inspires
positive murphys sign = patient stops breathing in and winces
45
other pain from cholecystitis
local pain below costal margin
referred pain to back of right scapula
referred pain to right shoulder
46
overview of the diaphragm
double domed musculotendinous structure separating thoracic cavity from abdominal cavity
lowers during inspiration, raises during expiration to as high as 5th rib
central tendinous, peripheral muscular
47
structures of diaphragm
3 parts: sternal, costal, lumbar
3 apertures: esophageal (T8), vena cava (T10) and aortic (T12)
2 crura: left and right next to aorta
5 arcuate ligaments: 1 median (over aorata), 2 left, 2 right (over psoas and quadratus lumborium muscles)
48
diaphragmatic blood vessels
superior and inferior phrenic arteries and veins
49
diaphragmatic nerves
C3-5 for motor and sensation
costal nerves for peripheral regions
thoracic splanchnic nerves
sympathetic trunks
50
posterior abdominal wall muscles
quadratus lumborum
psoas
iliacus
51
quadratus lumborum
from iliac crest and iliolumbar lig to 12th rib and transverse process of L1-5
fix 12th rib during respiration
52
psoas
from bodies of T12-L4 to lesser trochanter of femur
| chief flexor of thigh trunk
53
iliacus
from iliac fossa/sacral ala to lateral psoas tendon
assist psoas
inserts also onto lesser trochanter of femur
54
psoas abscess
collection of pus in the iliopsoas muscle compartment
more common in males
median age Is 44-58
55
primary psoas abscess
occur as a result of hematogeneous or lymphatic seeding from a distant site
risk factors include diabetes, IV drug use, HIV, infection, renal failure, and other forms of immunosuppression
56
secondary psoas abscess
```
occurs as a result of direct spread of infection to the psoas muscle from an adjacent structure
vertebrae
hip arthroplasty
GI tract
aorta
GU tract
```
57
psoas sign
RLQ pain produced with a patient extending the hip due to inflammation of the peritoneum overlying the psoas muscles and inflammation of the psoas muscles themselves
straightening the leg causes pain because it stretched the muscles
fetal position relieves pain
58
posterior abdominal wall nerves
1. subcostal nerve (T12)
2. iliohypogastric (L1)
3. ilioinguinal (L1)
4. genitofemoral (L1,2)
5. lateral femoral cutaneous (L2.3)
6. femoral (L2-4)
7. obturator (L2-4)
8. lumbosacral trunk (L4.5)
59
meralgia paresthetica
lateral femoral cutaneous nerve syndrome
caused when nerve is compressed
results in burning sensation felt in anterior, outer thigh
can be caused by sudden abdominal weight gain or too tight a belt or clothing
60
cremasteric reflex
test both genitofemoral nerve and L1/2 spinal cord integrity
genitofemoral nerve has a genital branch and a femoral branch
genital branch- mainly motor to the cremasteric muscles which rapidly pull the testicles toward the superficial inguinal ring
femoral branch- mainly sensory to skin on the medial thigh adjacent to external genitalia
**reflex is contraction of the cremasteric muscle when the skin of the superior medial part of the thigh is touches
61
sympathetic innervation to adrenal glands
no parasympathetics
| sympathetics = preganglionic > medulla > secrete adrenalin/epi
62
kidney location
retroperitoneal in posterior abdominal wall location from T12-L3
right side slightly lower
move a little with diaphragm
may drop lower due to peri-renal fat reduction
63
internal structures of the kidneys
```
cortex
medulla
renal pyramids
renal columns
renal papilla
renal sinus
minor calyx
major calyx
renal pelvis
ureter
```
64
kidney vessels
3 pairs of suprarenal arteries and 1 pair of suprarenal veins
renal arteries arise at L1/L2 intervertebral disc
right renal artery passes posterior to IVC
left renal artery passes posterior to left renal vein
arteries divide into 5 segmental branches
left renal vein receives left testicular/ovarian vein and passes anterior to aorta
65
kidney stones
renal and ureteric calculi
formed by inorganic salts and organic acids in kidney calices and fall into ureter
intermittent pain, ureter obstruction, infection of renal pelvis
66
horseshoe kidney
usually at the level of the lower lumbar vertebrae
ascent in development is prevented by the root of the inferior mesenteric artery
ureters arise from the anterior surface of the kidney and pass ventral to the isthmus in a caudal direction
67
horseshoe kidney epidemiology
1/600 people, males > females, 15% of turners syndrome females
68
symptoms of horseshoe kidney
often asymptomatic
| nausea, abdominal discomfort, kidney stones, UTIs at a greater frequency
69
perinephric abscess
pus from an abscess may force its way into the pelvis between the loosely attached anterior and posterior layers of the pelvic fascia
70
3 nonpaired arteries from abdominal aorta
1. celiac trunk
2. SMA
3. IMA
71
paired arteries from abdominal aorta from above down
1. inferior phrenic > suprarenal
2. middle suprarenal
3. renal
4. lumbar arerties ( 4 pairs)
5. testicular/ovarian
6. median sacral (single)
72
projection of abdominal aorta
```
diaphragm (T12)
celiac trunk (T12/L1)
renal (L1/L2)
SMA (L1)
IMA (L3)
aortic bifurcation (L4)
```
73
abdominal aortic aneurysm
diameter >5.5 cm in males and >5 cm in females
most common site (85%) for formation below renal arteries
presents as painless, pulsatile abdominal mass
pain and tenderness often in mid to upper back
74
AAA epidemiology
common in older adults >60
| appears to be a genetic link and runs in families
75
AAA outcomes
if untreated, mortality if ruptured is 85-90%
13th leading cause of death in US
screening with abdominal US is recommended for men 65-75 with history of smoking
76
celiac trunk and branches
```
at T12/L1, short anterior branch
gives off:
-left gastric
-splenic
-common hepatic
below diaphragmatic hiatus
above neck of pancreas
L1+ vertebral column
retroperitoneal
provides blood to foregut
```
77
left gastric artery
esophageal branch to esophagus
left side of lesser curvature of stomach
anastomoses with right gastric artery
78
splenic artery
retroperitoneal, coiling along superior border of pancreas
travel through splenorenal ligament to hilum of spleen
branches:
-posterior gastric to stomach
-pancreatic branches to pancreas
-short gastric to fundus
-left gastro-omental artery to greater curvature of stomach
79
common hepatic artery
retroperitoneal posterior to omental bursa
| bifurcates at pylorus into: hepatic proper artery (ascending) and gastroduodenal artery (descending)
80
hepatic proper artery
```
ascends inside hepatoduodenal ligament
branches:
-right gastric
-left hepatic
-right hepatic
```
81
gastroduodenal artery
descend retroperitoneally behind gastroduodenal junction
branches:
-right gastro-omental artery
-superior pancreaticduodenal arteries
82
superior mesenteric artery,
```
originates at L1 level, less than one vertebral body below celiac trunk, posterior to pancreas
branches:
-middle colic
-right colic
-ileocolic
supplies midgut organs
```
83
inferior mesenteric artery
```
originates at L3 level, 2 in above aortic bifurcation
descends toward rectum with 3 branches:
-left colic
-sigmoid
-superior rectal
supplies hindgut organs
```
84
ischemic colitis
often occurs at junction of 2/3 transverse colon from midgut with 1/3 transverse colon from hindgut, where hindgut meets soma in rectum, or where foregut meets midgut
85
hepatic portal venous system
portal vein- veins that have capillaries on both ends
hepatic portal vein- GI on one end, liver sinusoids on the other, no valves!
collect high nutrient blood from Gi organs and send to liver
after liver, blood returns to IVC via hepatic veins
86
relationships of portal vein
```
formed by splenic vein and SMV
behind pancreatic neck at transpyloric plane
anterior to IVC
within portal triad
anterior wall of omental foramen
enters porta hepatis
```
87
anastomoses with systemic veins
following venous plexuses allow portal vein to anastomose with systemic veins:
E= esophageal plexus (esophageal varices)
P= paraumbilical plexus (caput medusa)
R= rectal plexuses (hemorrhoids)
RP= retroperitoneal plexus
88
portal hypertension
increased pressure of hepatic portal vein due to scarring or fibrosis of the liver or obstruction of the blood flow
89
splanchnic nerves
greater (T5-9)- celiac ganglion, foregut organs
lesser (T10,11)- superior mesenteric ganglion, midgut organs
least (T12) - inferior mesenteric ganglion, hindgut organs
lumbar and sacral- superior and inferior hypogastic plexus, pelvic organs
pelvic- parasympathetic, pelvic organs
90
Hirschsprung disease
parasympathetic ganglion cells in the wall of large intestine do not develop before birth
without these nerves, the affected segment of the colon lacks the ability to relax and move bowel contents along
91
epidemiology of HD
1 in 5000
M:F 4:1
associated with trisomy 21
92
symptoms of HD
delayed passage of meconium >48 hr
abdominal distention
vomiting- may be bilious
diagnosis- rectal biopsy
93
treatment of HD
remove aganglionic portion of rectum/sigmoid colon/large intestine and connecting the neurologically intact portion to the anus (which has somatic innervation/control)
