3/2&3/3 GI Flashcards
non-selective beta-blockers
-can they cause hyper/hypokalemia?
- hyperkalemia
- inhibit the Na/K ATPase, so less K pumped into the cell, and more stays in plasma.
Overuse of diuretics can lead to
-metabolic acidosis or alkalosis
- alkalosis
- low volume = renin/aldo = potassium & H wasting = metabolic alkalosis.
- This = contraction alkalosis.
Do TB cavities usually have air-fluid levels?
-are they usually present in primary or reactivation TB?
- reactivation TB.
- usually no air-fluid levels.
Is pregnancy associated w/hyper or hypocoaguability?
hypercoag.
Osler Webber Rondu
-inheritance pattern
Auto Dom.
How does amphotericin B cause anemia?
suppression of renal EPO synthesis.
total parenteral nutrition
-affect on ALP?
-can increase ALP levels.
Granulomatous inflammation of the media
-think what disease?
Temporal (giant cell) arteritis.
Transmural inflammation of arterial wall w/fibrinoid necrosis
-think what disease?
Polyarteritis Nodosa
Gastroschisis vs omphalocele
- omphalocele is covered by peritoneum.
- omphalocele is “sealed”.
- both have inc AFP.
ant ab. wall defects:
-Rostral fold closure:
sternal defects
ant ab. wall defects:
-Lateral fold closure:
omphalocele, gastroschisis
ant ab. wall defects:
-Caudal fold closure:
bladder exstrophy
Jejunal, ileal, colonic atresia—due to:
- Can lead to bilious vomitting. Not caused by abnormal fetal development.
- due to vascular accident (apple peel atresia)
Midgut development:
-6th week:
midgut herniates through umbilical ring.
Midgut development:
-10th week:
midgut returns to abdominal cavity + rotates around SMA.
TEF
-results in oligo or polyhydramnios?
polyhydramnios.
Palpable “olive” mass in epigastric region and nonbilious projectile vomiting at ≈ 2–6 weeks old.
congenital pyloric stenosis
congenital pyloric stenosis most often seen in:
firstborn males.
pancreas: derived from:
foregut
Ventral pancreatic buds contribute to:
-pancreatic head and main pancreatic duct
The uncinate process is formed by:
-the ventral bud alone
Dorsal pancreatic bud becomes:
-body, tail, isthmus, and accessory pancreatic duct.
Annular pancreas: caused by dorsal or ventral pancreatic bud?
-how does it present?
- Ventral pancreatic bud abnormally encircles 2nd part of duodenum; forms a ring of pancreatic tissue that may cause duodenal narrowing.
- recurrent bilious vomiting in infant.
Pancreas divisum:
- how does it happen?
- how does it present?
- Ventral and dorsal parts fail to fuse at 8 weeks.
- usually asymptomatic.
- may get recurring bouts of pancreatitis.
Spleen:
- arises from what?
- arterial blood from where?
- arises in mesentery of stomach (hence is mesodermal) but is supplied by foregut (celiac artery).
- mesentery of stomach = mesogastrium.
Retroperitoneal structures
-mnemonic?
SAD PUCKER:
- Suprarenal (adrenal) glands
- Aorta and IVC
- Duodenum (2nd through 4th parts)
- Pancreas (except tail)
- Ureters
- Colon (descending and ascending)
- Kidneys
- Esophagus (lower 2 / 3 )
- Rectum (partially)
Falciform ligament
- connects:
- contains:
- derivative of:
- Liver to anterior abdominal wall.
- Ligamentum teres hepatis (deriv. of fetal umbilical vein).
- aka round ligament of liver
- Derivative of: ventral mesentery.
Hepatoduodenal ligament
- connects:
- contains:
- Pringle maneuver?
-Liver to duodenum
-Portal triad
-Hepatoduodenal ligament may be compressed between
thumb and index finger placed in omental foramen to
control bleeding.
Pringle maneuver?
Hepatoduodenal ligament may be compressed between
thumb and index finger placed in omental foramen to
control bleeding.
Gastrohepatic ligament
- connects:
- contains:
- why would you cut this?
- Liver to lesser curvature of stomach
- Gastric arteries
- May be cut during surgery to access lesser sac.
Which ligament can be cut to access the lesser sac?
-Gastrohepatic ligament
Gastrocolic lig.
- connects:
- contains:
- part of what?
- Greater curvature & transverse colon.
- Gastroepiploic arteries
- part of greater omentum.
Gastrosplenic lig.
- connects:
- contains:
-Greater curvature & spleen.
-Short gastrics, left gastroepiploic vessels
-
Splenorenal lig.
- connects:
- contains:
- Spleen to posterior abdominal wall.
- Splenic artery and vein, tail of pancreas.
Greater sac:
the general peritoneal cavity
-abdominal cavity inside peritoneum but outside
the lesser sac.
tail of pancreas
-contained in which ligament?
splenorenal lig.
musclaris externa
-2 layers:
- inner circular
- outer longitudinal
Meissners plexus:
- location:
- control of:
- submucosa
- secretions
Auerbach (myenteric) plexus:
- location:
- control of:
- muscularis externa
- contractions
Serosa:
Adventitia:
- serosa = intraperitoneal
- adventitia = retroperitoneal
Frequencies of basal electric rhythm (slow waves):
- Stomach:
- Duodenum:
- Ileum:
- Stomach—3 waves/min
- Duodenum—12 waves/min
- Ileum—8–9 waves/min
Gut wall
-What are layers w/in Mucosa?
- epithelium (absorption)
- lamina propria (support) = location of gastric glands.
- muscularis mucosa (motility)
Esophagus:
-histology
-Nonkeratinized stratified squamous epithelium.
Brunners glands:
- location:
- function:
- unique to duodenum.
- Secrete alkalinized mucus.
- its secreted into the crypts of lieberkuhn aka intestinal gland.
Where is the main site of lipid absorption?
Jejunum
Plicae circulares
- most prominent where?
- function?
- Jejunum
- inc. SA for absorption
Does the colon have:
- villi?
- crypts of leiberkuhn?
- no villi
- yes crypts
SMA syndrome:
- what is it?
- possible causes?
- occurs when the transverse portion (third segment) of the duodenum is entrapped between SMA and aorta, causing intestinal obstruction.
- dec. mesenteric fat can cause this, ie. crash diet.
Which vessel can be compromised during repair of AAA?
-what does it lead to?
- IMA
- ischemia of hindgut.
Parasymp. inn.
- foregut
- midgut
- hindgut
- vagus
- vagus
- pelvic
Vert. levels
- foregut
- midgut
- hindgut
- T12
- L1
- L3
Vert. levels
- foregut
- midgut
- hindgut
- T12
- L1
- L3
Ulcer in post. duodenum can peforate this artery:
Gastroduodenal artery
Foregut vasc: strong anastomoses exist between:
- Left and right gastroepiploics
- Left and right gastrics
Anastomoses if branches of ab. aorta blocked:
-Superior epigastric (internal thoracic/mammary):
inferior epigastric (external iliac)
Anastomoses if branches of ab. aorta blocked:
-Superior pancreaticoduodenal (celiac trunk)
inferior pancreaticoduodenal (SMA)
Anastomoses if branches of ab. aorta blocked:
-Middle colic (SMA)
left colic (IMA)
Anastomoses if branches of ab. aorta blocked:
-Superior rectal (IMA)
middle and inferior rectal (internal iliac)
transjugular intrahepatic portosystemic shunt (TIPS):
Shunt made between the portal vein and hepatic vein percutaneously relieves portal hypertension by shunting blood to the systemic circulation.
Portosystemic anastomoses:
-Portal: Left gastric ↔
Systemic: esophageal
Portosystemic anastomoses:
-Portal: Superior rectal ↔
Systemic: middle and inferior rectal
*these are NOT internal hemorrhoids.
Above pectinate line
- what type of hemorrhoids? painful?
- what type of cancer?
- art supply?
- venous drainage?
- internal hemorrhoids, not painful.
- adenocarcinoma
- superior rectal artery (branch of IMA)
- superior rectal v. => inferior mesenteric v. =>portal system.
Below pectinate line
- what type of hemorrhoids? painful?
- what type of cancer?
- art supply?
- venous drainage?
- external hemorrhoids, painful.
- squamous cell carcinoma
- inferior rectal artery (branch of internal pudendal artery).
- inferior rectal v. => internal pudendal v. => internal iliac v. => IVC.
- bypass 1st pass effect.
Anal fissure
- above or below pectinate line?
- ant or post?
- tear in the anal mucosa below the Pectinate line.
- if it was above pectinate line, would not be painful.
- post.
- Apical surface of hepatocytes faces:
- Basolateral surface faces:
- apical: bile canaliculi.
- BL: sinusoids
Which hepatic zone is affected 1st by:
-viral hepatitis
zone 1 (periportal)
Which hepatic zone is affected 1st by:
-ischemia
zone 3 (centrilobular)
Which hepatic zone is affected 1st by:
- metabolic toxins (as opposed to ingested toxins)
- includes acetaminophen
zone 3 (centrilobular) -this is where P450 system is.
Which hepatic zone is affected 1st by:
-site of alcoholic hepatitis
zone 3 (centrilobular)
Which hepatic zone is affected 1st by:
-contains P450 system
zone 3 (centrilobular)
Femoral sheath
-contents:
-femoral vein, artery, and canal (deep inguinal lymph nodes) but NOT femoral nerve.
Is femoral nerve contained in the femoral sheath?
No
External spermatic fascia
-derived from:
-External oblique
Cremasteric muscle and fascia
-derived from:
-Internal oblique
Internal spermatic fascia
-derived from:
-transversalis fascia
Is transverus abdominis muscle part of the spermatic cord?
No, but the transversalis fascia is (internal spermatic fascia).
Diaphragmatic hernia
-usually due to what?
defective development of pleuroperitoneal membrane.
Bowel sounds in lower lung field
-think what?
paraesophageal hernia
- GE junction is normal
- can result in lung hypoplasia
Direct inguinal hernia
- covered by what fascia?
- whats this fascia derived from?
- external spermatic fascia
- derived from external oblique
Leading cause of bowel incarceration?
Femoral hernia
Femoral hernia
-medial or lateral to femoral vessels?
Medial
-below inguinal ligament.
Polyethylene glycol
- what is it?
- name some other drugs in its class
- osmotic laxative
- magnesium hydroxide, magnesium citrate, lactulose.
Rectal prolapse in children
-think what disease?
CF
Vitelline duct
- aka?
- whats it connect?
- when does it go away?
- persistent one = ?
- omphalomesenteric duct
- lumen of midgut & yolk sac
- 7th week of fetal life.
- Meckel’s diverticulum
Zollinger Elison
-ulcers most commonly found where?
-duodenum.
SCC
-keratinization - good or bad sign?
-Good sign. Shows that properties of original tumor are still there. So its a well-differentiated, low-grade tumor.
Arsenic
- commonly contained in what household item?
- antidote?
- what will their breath smell like?
- insecticide
- dimercaprol (or succimer).
- garlic breath
Order of mutations needed in adenoma-carcinoma colon cancer pathway.
- APC - small polyp
- KRAS - growing polyp
- P53 & DCC- malignant transformation
Which IBD is more known for
- bloody diarrhea
- abdominal pain
- UC
- Crohns (via transmural inflammation - this causes pain)
*dont foorget Crohns has non-caseating granulomas.
Whats the only part of the duodenum thats not retroperitoneal?
First part.
Ligament of treitz
At the junction of the duodenum/jejunum.
-aka suspensory muscle of duodenum.
Common bile duct runs thru which part of which organ?
Head of pancreas
Rugal thickening & acid hypersecretion: think what disease?
Zollinger Ellison
H. pylori relationship to somatostatin.
- decreases somatostatin.
- chronic antral inflamm. => dec. # of delta cells (which make somatostatin) => inc. gastrin => inc. acid.
Whats the only GI hormone that inc. gastric motility?
Gastrin
CCK
- what stimulates it?
- Which cells make it and where?
- fat & protein in duodenum
- I cell (duodenum, jejunum)
CCK
-action
- inc. gallbladder emptying
- inc. pancreas secretions
- dec. gastric emptying
Gastrin
- what stimulates it?
- Which cells make it and where?
Only hormone made by stomach whos cells have neural innervation.
Gastrin
-G cells of antrum.
Whats the only digestive enzyme made by the stomach?
Pepsin
-pepsinogen activated by HCl
-This is why peptides stimulated gastrin secretion (stimulates HCl prod.)
(i think).
Whats the only GI hormone w/feedback inhibition?
Gastrin
-acidity turns it off.
Which amino acids are potent stimulators of gastrin production?
Phenylalanine and tryptophan are potent stimulators.
Glucose-dependent insulinotropic peptide
- AKA?
- trigger?
- function?
- gastric inhibitory peptide (GIP).
- fatty acids, amino acids, oral glucose
- dec. gastric H+ secretion
- inc. insulin release
- this is why oral glucose = more effective than IV glucose at causing insulin release.
why is oral glucose more effective than IV glucose at causing insulin release?
-same reason why its used up more rapidly.
-bc glucose in stomach triggers K cells (duodenum/jejunum) to make GIP (aka glucose-dep insulinotropic peptide) which inc. insulin release.
Glucose-dependent insulinotropic peptide
-which cells make it? where are they?
-K cells (duodenum/jejunum)
Motilin
- made where?
- fcn?
- trigger?
- s. intestine
- produce MMCs
- inc. in fasting state
Secretin
- who makes it?
- fcn?
- triggers?
- S cells (duodenum)
- inc. bile secretion, inc. pancreatic bicarb secretion, dec. gastric acid secretion.
-triggers: acid, fatty acids in lumen of duodenum
Somatostatin
- who makes it?
- fcn?
- triggers?
- D cells (pancreatic islets, GI mucosa)
- dec. all secretions. Inhibits insulin more so than glucagon so net: causes hyperglycemia.
- triggers: low pH.
- Inhibited by vagal stim.
*Antigrowth hormone effects (inhibits digestion and absorption of substances needed for growth)
What causes dec in somatostatin prod, chronically.
H. pylori & chronic antrum inflammation.
-decreases delta cells.
COX-2 relationship w/colon cancer
- inc. COX-2 activity has been shown in some forms of colon cancer & inherited polyposis syndromes.
- pts taking aspirin have lower incidence of colon cancer.
Is CF associated w/diarrhea or constipation?
-malabsorption diarrhea (steatthorea)
What type of channel is the H/K exchanger on gastric parietal cells?
ATPase
What bug causes pneumocystis pneumonia (PCP)?
Pneumocystis jiroveci
3 main causes of HIV esophagitis & appearance.
- candida = white pseudomembrane
- HSV-1 =punched out ulcers
- CMV = linear ulcers
Left or right sided colon tumors = more likely to cause obstruction?
Left (left side more narrow)
-right side usually causes bleeding.
Ulcer vs Erosion
- Ulcers can extend into the submucosa.
- Erosions are in the mucosa only.
Which cells do carcinoid tumors arise from?
enterochromaffin (endocrine) cells of the intestinal mucosa.
2nd part of duodenum:
-foregut or midgut?
- foregut
- last section of the foregut.
Most common appendix tumor
carcinoid tumor
Vasoactive intestinal polypeptide (VIP)
- made where?
- fcn?
- trigger?
- Parasympathetic ganglia in sphincters, gallbladder, small intestine.
- fcn: inc. intestinal water and electrolyte secretion, inc. relaxation of intestinal smooth muscle and sphincters.
- also inhibits gastric acid secretion.
- trigger: distention & vagal stim.
- inhibited by: adrenergic input
VIPoma
- most commonly found where?
- Sxs?
- Tx:
- tail of pancreas
- Copious Watery Diarrhea, Hypokalemia, and Achlorhydria (WDHA syndrome).
- octreotide
*aka “pancreatic cholera”.
Basic Triggers: Carbs: Amino acids: Fats: Acid:
Carbs: GIP
Amino acids: Gastrin
Fats: CCK
Acid: Secretin
Location of chief & parietal cells in gastric glands.
-which ones are deeper?
Chief cells: deeper in gastric glands than parietal cells
-Parietal cells are located in superficial region of the
gastric glands, below the simple columnar epithelium which secretes the mucus.
How does vagus stimulate G cells to make gastrin?
- Using gastrin releasing peptide = GRP (basically the same thing as ACh).
- So vagus doesn’t release just ACh!
Will atropine block stim. of
- parietal cells (HCl)?
- G cells (gastrin)?
- yes
- no (G cells stimulated by vagus n. releasing GRP).
