GI Tract/Contrast Flashcards
0
Q
Negative contrast media
A
Low atomic #
Decrease attenuation of the X-ray beam
-air
-carbon dioxide
1
Q
Purpose of contrast media
A
To visualize detail of anatomy, area of interest must differ in density
2
Q
Positive contrast media
A
High atomic #
Increase attenuation of the X-ray beam
-barium sulfate
-iodine
3
Q
Barium
A
Atomic # 56
Positive contrast
Chalk like, not a solution, held in suspension
Subject to separation - flocculation
4
Q
Barium
A
Various consistencies/concentration
- very thin (swallowing evaluation)
- thin (esophagus, stomach, small intestine)
- moderate (dual contrast esophagus, stomach)
- thick (large intestine)
- very thick/paste (esophagus)
5
Q
Contraindications for barium
A
Mixtures are contraindicated if any chance exists that the mixture might escape the peritoneal cavity.
6
Q
When barium can’t be used
A
Water soluble iodinated contrast should be used if there is a chance of a barium mixture escaping the peritoneal cavity
7
Q
Water soluble iodine is used in place of barium
A
For perforated bowel or pre-surgical procedures
8
Q
A potential risk associated with water soluble contrast agents especially geriatric patient
A
Dehydration
Have patients push fluids for the next 48 hours post procedure
9
Q
Advantage of dual contrast
A
Small lesions are not obscured
Mucosal lining of the stomach can be more clearly visualized
10
Q
Studies preformed using contrast media
A
IVP Cystography Biliary studies Vascular imaging Myelography Arthrography CT scanning
11
Q
Lower concentrations of contrast media are required for
A
Bladder studies due to the large amount required to fill the bladder
12
Q
Higher levels of contrast media are used for
A
Excretory urography
13
Q
Non ionic contrast media
A
Less likely to cause an adverse reaction
14
Q
Vein puncture and injection of contrast media
A
Is an invasive procedure
Patients must be aware of risk.
Underage and impaired require consent from guardian prior to procedure
15
Q
Qualities of Iodinated contrast agents that contribute to discomfort
A
Viscosity
Toxicity
Osmolality
16
Q
The concentration of iodine in ionic contrast is
A
50-70%
17
Q
The higher the osmolality the greater
A
The chance of reaction
18
Q
The lower the osmolality
A
The less the chance of reaction
19
Q
As an act of caution with contrast media
A
Patients should not be left alone after an intravenous injection, most reactions occur immediately, within 5 minutes
20
Q
The three most common reactions that occur in many patients and do not require medication
A
Warmth or temporary hot flash
Flushing
Metallic taste in mouth
21
Q
The four general categories of contrast media reactions
A
Vasomotor
Anaphylactic reaction
Vasovagal reaction
Acute renal failure
22
Q
Symptoms of vasomotor reaction
A
Anxiety, lightheaded, nausea, syncope, mild scattered hives
23
Q
Anaphylactic reaction
A
True allergic reaction resulting from the introduction of iodinated contrast media.
Medical assistance must be provided without delay.
24
Symptoms of anaphylactic reaction
```
Moderate to sever urticaria (hives)
Laryngospasm - choking from larynx closure
Angioedema - swelling of soft tissues
Hypotension - low blood pressure
Tachycardia - greater that 100bpm
```
25
Severe Anaphylactic reactions occur in approximately
1 in 14,000 contrast procedures
26
Vasovagal reaction
Life threatening allergic reaction resulting from the introduction of iodinated contrast media, which stimulates the vagus nerve
27
Signs of Vasovagal reaction
Hypotension - BP<50BPM
| No detectable pulse - declare code
28
Acute renal failure
Anaphylactic reaction in which kidneys shut down, may not be obvious for as long as 48 hours after study.
29
Mild reactions include:
```
Mild nausea and vommitting
Extravasation (leak)
Sneezing
Itching
Mild hives (urticaria)
Vasovagal (fainting)
```
30
Extravasation
Mild reaction at the injection site where contrast media leaks from the vein into the surrounding tissue. Pain, burning and numbing may occur.
31
Moderate reactions include:
Excessive urticaria (hives)
Tachycardia
Excessive vommitting
32
Severe reactions
```
Very low blood pressure
Cardiac or respiratory arrest
Loss of consciousness
convulsions
Difficulty breathing
Cyanosis
Anaphylactic shock
```
33
Diabetic patients & geriatric patients
Should be kept well hydrated before exam to decrease dehydration and the chance of contrast induced renal failure
34
Metformin glucophage
Drug used to treat diabetes and is an absolute contraindications to the administration of iodinated contrast media, dues to the possibility of contrast induced renal failure.
Should be discontinued 48 hours before exam and resumed no earlier than 48 hours after.
35
Blood urea nitrogen (BUN)
Normal range is 8-25 mg/mL
| Blood levels indicate the status of renal function
36
Creatinine blood level
Normal range is less than 0.6-1.5 mg/dL
| Levels indicate the status of renal failure
37
GFR - glomerular filtration rate
Test used to check how well kidneys are functioning. Estimates how much blood passes through the glomeruli each minute.
38
Contrast studies other than GI tract
```
Excretory urography
Nephrograms
Cystography
Retrograde urography
Oral cholecystography
Intravenous Cholangiogram
Percunaneous transhepatic cholangiography
T tube surgical cholangiography
ERCP - endoscopic retrograde cholangiopancreatography
Myelography
Contrast arthrography
```
39
Atomic weight determines the degree to which it will attenuate radiation
Air gasses absorbs less radiation that soft tissue, air appear black or very dark (negative contrast).
Common uses - arthrography, myelography, double contrast BE
40
Aqueous
Principle solvent for iodinated contrast, mix readily with blood, and only type of contrast suitable for IV injection
41
Bolus
Substantial amount of contrast delivered rapidly via IV catheter or butterfly set.
42
Iodine concentration determines X-ray attenuation
Higher concentration = greater contrast
| Greater concentration = greater viscosity! greater osmolality and toxicity
43
Osmolality
The number of particles in a solution per kg of water
44
Viscosity
Measure of resistance of fluid flow
45
Toxicity
Relates to the chemical configuration of molecules
46
Two common types of iodinated contrast
Diatrizoate Meglumine - less toxic
Diatrizoate sodium - small molecules with more iodine per molecule.
47
Low osmolality contrast agents
Introduced in 80's, less toxic and more comfortable for patient.
Used for most imaging needs
48
Water soluble contrast injected how?
Intravascular. Excreted by kidneys.
49
Toxicity can be caused
By the reaction of contrast to other medications.
Always flush catheter with saline before and after contrast injection to avoid reactions.
50
History of patient
Carefully take their history and document all allergies, routine meds, etc.
51
Asthma
Patients with asthma have a higher risk of reaction to contrast.
52
Premedication
Patients per educate with Benadryl to reduce risk of reaction.
53
IVP
intravenous pyelogram.
Signifies visualization of kidney pelvis
54
IVU
Intravenous urogram
Entire urinary tract is visualized.
55
Cystography
Contrast studies of the urinary bladder.
Bladder is filled by retrograde injection of water-soluble contrast.
56
VCUG
Voiding cystourethrogram
Identifies vesicoureteral reflux (backflow of urine from the bladder into uterus)
57
Retrograde urography
Long slender catheters inserted retrograde into the uterus to visualize anatomical form of pelvis, calyces and ureters.
Lower risk of contrast reaction versus IV injection.
58
Biliary system - stones and cholecystitis
Before the 1990s were treated with open surgery
Now treated with laparoscopies and fiber optics - much easier on patient.
59
Oral cholecystography
Images taken every 20-30 minutes after a fatty meal to identify stones and/or gallbladder function. Ultrasound is preferred method. Diet prep done prior to exam.
60
IVC
Intravenous Cholangiography
61
Myelography
Demonstrates internal surface of spinal canal, diagnoses conditions caused by deformity or crowding.
62
Lumbar puncture
At level of L2-L3 interspace. Collect CSF to be delivered to lab stat.
63
Contrast angiography
Contrast radiography of joints used to detect injury/disease in joint capsule. Shoulder most common. Joint May be stressed.
Post injection patients must perform range of motions to distribute contrast.
64
Sequence
Order in which exams are to be preformed. Starting with any exams not requiring contrast, labs, fiber optic exams, ct exams, urinary tract exams, biliary exams, BE, esophageal exams, UGI, SBFT.
65
Inpatients
Nurses are responsible for prepping patients. Take history and make sure prep was completed.
66
Outpatients
Issue printed instructions! Have the patient repeat the instructions
67
Scout exam
Initial image to evaluate patient prep, reveals any anatomical abnormalities in advance, helps fine tune technique
68
GI prep
Most commonly CLEANSING
Diet
Cathartics
Suppositories
Enemas
69
Diet prep for GI exam
Low residue for several days with high water intake - rapid waste output - less residue.
24hrs prior - clear liquids only, no carbonated drinks
NPO 8-12 hours prior
70
Cathartics
Strong laxative (5 types)
```
Bulk - fiber
Lubricant - mineral oil
Emollient - stool softener
Saline - indirectly increases motor activity of bowel
Stimulant - dulcolex/exlax
```
71
Suppositories
Stimulates peristaltic action of lower bowel. Deposited 2-3 inches into rectum. Patient should retain suppository for 30 minutes.
72
Enemas
Filling of the colon with fluid to aid dislodging and flushing out fecal material.
Need enema bag, IV pole, 1000 mL of water.
Make sure enema bag is 18" above anus, not too high.
73
Three groups of contrast media
Barium sulfate
Water soluble iodine
Gasses (air)
74
Barium sulfate
Invert inorganic salt, very dense (56), not absorbed by soft tissue. Bone absorbs more radiation than surrounding tissues, way less dense (14). Comes in liquid suspension or powdered form to be mixed. Serve COLD.
75
Viscosity
Thickness. Important for GI exams.
76
Air contrast
Absorbs less radiation than either soft tissue of other contrast media.
77
Glucagon
Slows peristalsis, used to relax and smooth muscles of GI tract.
78
Defecogrpahy
Evacuation proctography
Evaluates defecation.
High density barium paste used mixed usually with potato buds
79
Valsalva maneuver
Bearing down.
80
Double contrast UGI
Patient takes gas producing tablets before drinking barium.
Have patient refrain from belching during exam.
81
Hypotonic duodenography
Detects lesions in the duodenum distal to the duodenal bulb. Passage of a tube via the mouth or nose to the duodenum. Diagnoses pancreatic cancer.
82
Aortography
Administered through the arterial catheter to visualize the abdominal and thoracic aorta, using omnipaque 350 or optiray 350
83
Angioradiography
Administered through the arterial catheter to view the heart and surrounding great vessels using imagopaque 350, iomeron 350 or visipaque 350
84
Digital subtraction angiography (DSA)
Administered through the arterial catheter to visualize the cerebral vasculature, aorta, and branches using lomeron 350, imagopaque 350 or omnipaque 140
85
Digital subtraction angiography
Administered intravenously to view the cerebral vasculature, aorta and branches using iomeron 350 or conray 43
86
Peripheral artiography
Administered via a arterial catheter to view the arteries of the extremities using visipaque, hexabrix, isovue300, md76
87
Peripheral venography
Administered intravenously to view the veins of the extremities using conray43, imagopaque 200 or 250, or visipaque 270
88
Cerebral angiography
Administered via an arterial catheter to view the cerebral vasculature using hexabrix, imagopaque 300, md76, or optiray 320
89
Selective visceral arteriography
Administered via an arterial catheter to view renal, celiac, splenic, or coronary arteries for example, using hexabrix, imagopaque 300, md76, optiray 320
90
Cholangiography, operative and postoperative
Administered injection direct via t tube to view the common bile duct
91
Cholecystography
Administered orally to view the gallbladder
92
Endoscopic retrograde cholangiopancreatography (ercp)
Administered via a catheter via endoscope to see the common bile duct and pancreatic duct
93
Percunaneous transhepatic cholangiography (PTC)
Direct injection to view the common bile duct
94
Myelography
Administered via intrathecal injection via lumbar puncture or view the spinal canal (subarachnoid space)
95
Discography
Administered via a direct injections to see the intervertebral disk
96
Excretory urography
Administered intravenously to view the kidneys, ureters, and bladder
97
Retrograde urography
Administered ureteral catheters via cystoscope to view the kidney pelvis, calyces and ureters
98
Cystourethrography
Administered via a direct injection via Foley catheter to view the urinary bladder and urethra
99
Esophageal
Oral administration to view the esophagus
100
Upper GI series
Orally administered to view the esophagus, stomach and duodenum
101
Lower GI series
Administered via a rectal catheter to view the colon.
102
Small bowel series
Orally administered or enteric lysis to view the small intestine.
103
Arthrography
Administered via direct injection to see joint (knee, shoulder, etc)
104
Computer tomography
Administered intravenously to view anatomy of interest using imagopaque or conray
105
Computed tomography (2)
Oral administration for enhancement of GI tract using gastrografin, hypaque sodium oral powder, or MD-gastroview
106
Hyaterosalpingograhpy
Administered directly via cervical cannula to view the uterus and Fallopian tubes.
107
Lymphography
Administered via direct injection into lymphatic vessels in feet to view the lymph vessels and lymph nodes
108
MRI
Intravenous administration to view brain, spinal cords and vascular structures.
