Gastrointestinal System

alkathryn's version from 2016-10-07 04:19

GI System

Question Answer
AnatomyMouth, pharynx, esophagus, stomach, s/L intestine
Salivary gland functionssaliva, enzymes breakdown food
Salivary gland count6 glands, 3 pairs
Esophagus functionfood passage
Stomach functionsstorage, digestion
Small intestine functionabsorption, digestion
Large intestine functionstore decal matter
Accessory organsPancreas, liver, gallbladder


Question Answer
Liver lobulesHepatocytes 85%, kupffer cells 15%
Liver blood supplyPortal vein, hepatic artery
Liver functionsMetabolism, storage, produce bile, detoxification, regulate body temp, blood volume, and fight off diseases
Jaundice is a ____, not a _____symptom, disease
Jaundice isyellow discoloration of the skin, mucus membranes and sclera of the eye
Jaundice is due tohigh amounts of bilirubin in the blood
Jaundice symptomsN/V, abd pain, dark urine
Cirrhosis characterized byloss of functioning liver cells and decreased blood flow through liver
Cirrhosis etiologyalcohol, viral hepatisis
Cirrhosis symptomsmalaise, anorexia, early satiety, dyspepsia
Cirrhosis txliver transplant, shunt
Viral hepatitis is anacute disease
Viral hepatitis due todifferent viral agents
Viral hepatitis symptomsflu-like, jaundice
Hep A akainfectious hepatitis
Hep A is (acute/chronic)acute onset
Hep A contracted throughcontaminated water, food or feces
Hep A is ___ comparativelymild illness
Hep A incubation period2-6 weeks
Hep B is frominjury to liver cells caused by HBV
Hep B transmitted byblood or body fluids
Hep B incubation period2-6 months
Hep B treatmentnone
Hep C transmitted byblood or body fluids, blood transfusions or sexual contact
Hep C incubation period6-12 weeks
Hep C causes an increased risk ofcirrhosis and liver cancer
Hep C txantiviral agents and ribavirin

Liver/Spleen Imaging

Question Answer
RphxTc-99m Sulfur Colloid
Dose5-10 mCi
Biodistribution85% liver, 10% spleen, 5% bone marrow
Limit of resolution for lesions/masses1cm
Contraindicationsbarium in colon, breasts can cause cold defect
Indicationsabd masses, diffuse liver disease, liver size/shape, jaundice/ascites, trauma puts, pre-op liver mets, hepatic abscess
SC kit akasodium thiosulfate
SC kit syringe A containshydrochloric acid
SC kit syringe B containsbuffer solution
If you boil too longclump
If you boil too shorttoo small
Size of colloids0.1 to 1 micron
Procedureinject and wait 15-20 mins
Viewsant, rao, r lat, post, l lat, lao, ant marker
Normaleven distribution of liver and spleen. little or no uptake in marrow.
If very vascular will appearhot
Hepatic tumors can behot or cold
Hepatitis appearsdiffuse, decrease uptake
Cold defectsmetatstic tumors, hepatomas, adenomas, abscess, cyst, hepatic trauma
Hot spotstumor, focal nodular hyperplasia
Over production of cells showshot
Artifactsbreast attenuation, lung visualization


Question Answer
HIDA is a function study ofliver and gallbladder
Rphx excreted asbile
Rphx flowsR/L hepatic ducts, hepatic/cystic ducts, common bile duct
Cholelithiasis akagallstones
Cholelithiasis is %80% cholesterol stones, 20% bilirubin calcium stones
Cholelithiasis symptomsRUQ pain, N/V, and or fever
Cholelithiasis tx symptomaticcholecystectomy
Cholecystitis isinflammation of the GB
Acute Chole is95% from stones obstructing the cystic duct
Chronic Chole isassociated with stones, repeated attacks
Pain meds can causefalse negative
Acute Chole treatmentfluids, pain meds, antibiotics, surgery
Chronic Chole treatmentlow fat diet, surgery
HIDA indicationscholecystitis, cholelithiasis, biliary dyskinesia, GBEF, leaks
Contraindicationsnot NPO, no cck if gallstones, pain meds
RphxTc-IDA, Tc-DISIDA (disofenin/hepatolite), Tc-Choletec (membrofenin)
Dose5-10 mCi
MOLactive transport
PrepNPO 4-6 hr, no pain meds, (demerol or morphine)
Non-visualization of GB remediescold water, walk, turn pt on right to see GB on left to see bowel, delays
4 hour Liver, NO bowel, NO GBblockage up high, obstruction in hepatic duct
4 hour Liver, Bowel, NO GBblockage in cystic duct, acute cholecystitis
4 hour Liver, GB, NO bowelchronic cholecystitis (gallstones), partial obstruction
Kinevac causesprompt contraction of GB in 5-15 mins
Kinevac ___ the ___relaxes the sphnicter of Oddi
Kinetic used to determineEF
Kinevac dose0.01-0.02 mug/kg
Kinevac contraindicationintestinal obstruction
Morphine ___ the ___contracts the sphincter of Oddi
Morphine is used whenliver and bowel are visualized but NOT GB
Morphine acts byincreasing bile duct pressure and causing GB to fill if cystic duct is patent
Morphine dose0.04 - 0.1 mg/kg IV over 2-3 mins
Normal studyliver immediate, GB/hep&CD duct within 5-20 mins, GB empty within 1 hour
Normal EF>35%
Morphine dropsblood pressure - always check
Morphine contraindicationspancreatitis
If GB appears after GB admin, diagnosischronic cholecystitis
Acute whole would appearnon-visualization of GB at 4 hours
Chronic chole will appearvisualization of GB after 4 hours or admin of morphine
Obstruction will appearnon-visualization of GB and bowel
Cardiac uptake within 10 minspoor liver function
False positives/negativesNPO >24 hour, pain meds/demerol, no CCK

Gastric Emptying

Question Answer
Gastritis isinflammation of the gastric mucosa
Gastritis etiologyH. pylori, alcohol/tobacco, duodenal reflux, pernicious anemia
Chronic gastritis symptomsasymptomatic
Acute gastritis symptomsepigastric pain, N/V, hematemesis
Gastritis treatmentantibiotics, no alcohol or tobacco
Peptic ulcer is achronic solitary lesion that can occur in any part of the GI tract exposed to peptic juices
Peptic ulcer etiologyuse of non steroidal anti-inflammatory drugs, tobacco, stress
Possibly peptic ulcer symptomsepigastric apin, heartburn, N/V, weight loss
Gastroparesis isdelayed emptying of good
"Dumping syndrome" israpid gastric emptying
Dumping syndrome may occurafter gastric or duodenal surgery, duodenal ulcers
Functions of the stomachsecretions, reservoir, motility, antibacterial barrier
Stomach resevoir holds1000-1500mL of food diluted with secretions
Gastric patient prepNPO 6-8 hours/post midnight, no stomach or pain meds
Solid phase rphxtc-99m sulfur colloid
Solid phase SC dose200uCi - 1 mCi PO
Gastric eat within15 mins for baseline
Liquid rphxtc-99m DTPA
Liquid dose200 uCi - 1 mCi PO
Bioroutingstomach to GI tract
Critical organsmall intestine
Start imagingimmediately
Possible viewsANT or LAO or back to detector
Can be imaged forevery 15 mins for 90-120 mins or dynamic
Interventional drugsreglan and erythromycin
Reglan is used when there is aknown problem to assess if it will help in daily function
Reglan is used toaccelerate emptying (opens pyloric sphincter)
Reglan dose10 mg IV over 2 min
Erythromycin allowsstomach to empty contents
Erythryomycin dose2.8 mg/kg in 25-50 mL IV
Process bydrawing ROI around stomach
% retained =remaining activity cts / original activity cts
Normal liquid study half-life10-45 mins
Normal liquid study % at 1 hour80%
Normal solid study half-life50-90 mins
Normal solid study % at 1 hour63%

GI Bleed

Question Answer
Works withactive or intermittent bleeding
Accurate forlower GI bleeds
More _________ than X-raysensitive
Rphxstc-99m labeled RBCs, tc-99m sulfur colloid
Sulfur colloid acts onactive bleeds only
SC leaves a timing window of15-20 mins before RES is visualized, making it a downfall
Tagged RBCs critical and targettarget-heart, critical-blood
MOLcomparmental bloodstream
In-Vivo lowest tag efficiency80-90%
Best tag efficiency is withIn VITRO
In-Vivo utilizesPYP (same as muga)
In-Vitro isdraw blood, ultra tag kit, how we do it at clinic
In-vitro adds35-45 mCi of pertechnetate
In-Vitro is good for30 mins after prep
In-Vitro tagging efficiency>97%
SC dose10-15 mCi IV
SC targetliver
SC criticalspleen
SC procedureonly 20 minutes
Both rphxs are injected asbolus
RBCs imagingflow for 60 mins or statics every 5,10,15,30,45,60. Can do delays
RBCs allows for24 hour delay imaging
If stomach is seenfree tech bad tag
Can tell its GI by seeingheart, no bladder (rbcs)
Can tell it's Meckels bybladder, pretty stomach, leaves heart

Meckel's Diverticulum

Question Answer
Most commoncongenital irregularity of the GI tract
Involvessmall intestine and terminal ileum
It is an incompleteembryonic connection between intestine and umbilicus
Size1-12 cm
In children symptomsrectal bleeding
In adults symptomsobstruction volvulus or intussusception
More common inmales
50% containectopic gastric mucosa
Dose10-15 mCi IV
MOLactive transport to mucus cells of stomach
Contraindicationbarium or contrast studies (skews the stomach)
Pt prepNPO 6-12 hours, no barium, empty bladder
PositioningANT over abd
Imagingstatics every 5 mins for 1 hour
Pharma treatmentcimetidine, pentagastrin, glucagon
Cimetidine dose20 mg/kg/day PO, 1-2 days prior to scan
Cimetidine is ahistamine antagonist
Cimetidine blocksthe secretion of rphx from ectopic gastric mucosa into the bowel -- increases gastric uptake
Cimetidine helps improvethe lesion to background ratio
Pentagastrin dose6 ug/kg subQ, 15 mins prior to inj
Pentagastrin increasesectopic gastric mucosa uptake, decreases background
Glucagon dose50 ug/kg IV
Glucagon helps todecrease motility and peristalsis of small bowel, increase rphx in mucosa
Normal study seesgastric, renal, bladder, heart, liver, spleen...stomach in time
Abnormal studymeckel's seen -- stays in same location -- within 30-60 mins
Meckels' appears within30-60 mins
False positivebarium, urinary tract activity, inflammation or tumors
False negativesno mucosa, rapid washout

RBC Liver

Question Answer
Used to evaluatehemangiomas
Hemanggiomas arehighly vascular
Will appearcold at first, hot rim later (tight blood vessels take time to get rphx into)
More common inwomen
Rphxlabeled RBCs
Dose25-40 mCi IV
Imaginginitial flow (hot or cold) then 1-2 hour delays and all around with Rs
Negativeheart, spleen kidneys...homoegeneous light liver

Salivary Glands

Question Answer
3 pairsparotid, submandibular, sublingual
Pairs usually involvedparotids
Growth rateslow
_________% non-malignant80
Sjogren's syndromeautoimmune disorder with decreased lacrimal and salivary secretions
Patient does what to stimulate glands prior to injchew gum or lemon juice
Dose8-12 mCi
MOL active transport
ImagingANT initial flow, statics 2 5 10 15 20 30 mins
Imaging instructionsrefrain from swallowing, hyperextend chin
Normal resultssymmetrical uptake in salivary, thyroid, nasal
Abnormal resultsnon symmetrical uptake, patchy decreased (sjogre's), increased (warthins), cold abscess

Gastroesophageal Reflux

Question Answer
Evaluatesesophageal transit
Achalasiaspasms of the lower esophageal sphincter
Pt PrepNPO
Esophageal useswater
Esophageal looks atmotility
Gastro usesOJ
Gastro looks atreflux
Dose300 uCi
Imagingbolus swallow, swallow every 15 secs for 9 mins, image every 15 secs
ProcessROI around entire esophagus
Normal esoph transit>90% after 10 mins
Normal gastro reflux<4-5%