Ch5 Iv And Contrast Flashcards
1
Q
Contrast agent p 4
A
Compound usually pharmaceutical in nature, which when administered to a patient , may improve the sensitivity and specify clinical diagnoses
2
Q
Most contrast agents used do what? P 4
A
Caused perfumed tissues to enhance
Appear brighter on images because attenuated xray beam
3
Q
Negative contrast agents p 4
A
Air
Water
4
Q
Two things negative contrast agents do? P 4
A
Distend structure
Improve visualization of internal structures
5
Q
Five contrast media categories p 4
A
Intravenous Oral Rectal Intrathecal Intraarticulate
6
Q
Increases the attenuation of X-ray beam and causes enhancement? P 6
A
Iodine
7
Q
Intravenous contrast p 6
A
Injected into bloodstream
8
Q
Iodine causes what on ct film? P 6
A
Brighter image
9
Q
Enhancement p 6
A
Increased brightness by contrast on ct image
10
Q
Ionic agents p 6
A
Break into charged particles in the bloodstream
11
Q
Non-ionic contrast p 7
A
Do not divide into charged particles rather entire until excreted by kidneys
12
Q
Effects how well contrast tolerated p 7
A
Less an agent breaks down into greater number charged particles , the better tolerated
13
Q
Osmolality p 7
A
Concentration of molecular particles in contrast agent
14
Q
Two iv contrast osmality groups
A
Low osmolar
High osmolar
15
Q
Non ionic contrast and osmaliity p 7
A
Low osmolar category due to lower concentration of particles
16
Q
Lower the osmolity effects on the patient p 7
A
Better tolerated by patient
17
Q
Why need drink lots water both before and after contrast exam? P 7
A
Hypertonic solutions compared to blood plasma cause movement of water within tissues into vascular space, causing dehydration
18
Q
Viscosity p 8
A
Measure of thickness of liquid related to frictional force of molecules of substance as they pass one another
19
Q
______the contrast the more force required to administer the solution . Therefore , _____ viscosity is better
A
Thicker
Lower
20
Q
Kidneys have hard time clearing ____ molecules out blood p8
A
Large
21
Q
Minor reactions
A
Nausea Chills Vomiting Feeling warm Minor hives Metallic taste Itching Shaking Headache Dizziness Sweating
22
Q
Moderate reactions
A
Moderate hives Change pulse rate Hypotension/ hypertension Wheezing Bronchospasm/ larygynospasm Facial edema
23
Q
Two mechanisms of reactions p 8
A
Chemotoxic reaction
Idiosyncratic
24
Q
Chemotoxic reaction p 9
A
Effected by total volume of the agent and rate of injection
25
Idiosyncratic reaction p9
Reactions not caused by injection rate and type
26
Ionic, high osmolar contrast has more molecular particles than low osmolar contrast resulting in ? P 10
Osmotic process- draw water from body tissues and cells
27
____ reduces viscosity of contrast prior to injection
Warming
28
_____ the viscosity the more force to inject causing injection site pain
Thicker
29
______injection rates and _____ concentration of contrast have increased reactions
Higher
| Higher
30
Pre medicating patient with before injection? P 12
Antihistamine
| Steroid
31
Minimizing adverse reactions p 13
Read al labels
Know non ionic contrast for diabetics and diseases of liver or kidneys
Low osmolity and low viscosity the better
Warm contrast to body temperature to reduce viscosity
Pre medicate with antihistamine and steroid to recuse idiosyncratic reactions
32
Precaution p 13
Condition that would warrant medical decision as to whether the benefits of the exam outweigh the risks posed to the patient
33
Contraindication p 13
Condition that would preclude a patient from having a study performed in a given manner
34
Extra action contrast agents with these diseases : p 14
```
Liver
Kidney
Thyrotoxicosis
Myelomatosis
Diabetes
Multiple myeloma
Sickle cell
Pheochrmocytoma
Hyperthyroidism
History of reaction
Asthma
Hay fever
Food allergies
Congestive heart disease
```
35
Iv contrast to pregnant lady when ? P 14
No other modality can obtain diagnostic info
If the ct would affect the fetus
If ct. can't wait until after pr egnancy
36
When to breast feed after ct injection p 14
Safe right after or if mom wants wait 24 hrs
37
Bun
5-25 mg/dl
38
Creatinine
0.6-1.7 mg/dl
39
Gfr
95-120 ml/min/1.73 m2
40
eGFR
>60
41
In healthy adult, How long for 50% of all contrast out blood stream? P 15
2hrs
42
Normal pt
10-14 sec
43
Normal ptt
20-40 sec
44
Normal inr
0. 9-1.3
2. 0-3.9 for patient on anticoagulant
2. 5-3.5 patients with high risk clot formation
45
Platelet count
150,000/mm3- 400,000/mm3
46
Why fasting important for injection ? P 16
Perstslsis creates motion
Vomiting
47
Diabetic or renal insufficiency patients and injection p 17
Low,osmolar
Non ionic
48
Metformin ( glucophage, glucovance ) acr 3 caogries
No metformin 48hrs after exam
Metformin resumed after Blooodwork is done to confirm kidney function
Patients with renal insufficiency should stop metformin before injection and should be monitored after
49
Technique used prior intravenous injection p 18
Aseptic technique
50
Optimum injection enhancement is achieved at higher injection rates of ___-____
5-6 ml/sec
51
Power piccs are used at injection rates of ________
Up to 5ml/sec
52
Regular picc lines and injection p 18
Can't be used for injection
53
Type gauge needle p19
18-22 gauge
54
22 gauge needle allows rates up to ?
3 ml /sec
55
Required for 5/ml
18 gauge needle injection rate
56
If site hand
Slow injection rates
57
Most common site for injection p20
Basilic vein in cubital fossa
58
How distend vein for injection p 20
Apply tourniquet
Have patient pump hand
Slap vein
Apply heat
59
Signs of extravastion what must be done? P 22
Stop injection
60
Venous air emboli p 22
Air introduced into vein during injection
61
Three tissue enhancement phases p 23
Bolus phase
Non equilibrium phase
Equilibrium phase
62
Bolus phase p 23
Enhanced begins when contrast injected
Significant density difference between abdominal aorta and inferior vena cava
Bolus moves away from heart
Optimal quality cta imaging
63
Non equilibrium phase p 23
10-30 HU density difference between abdominal aorta and inferior vena cava
Bolus disperses into capillaries then into the veins
Best differentiation in soft structures
64
Since _______has dual supply , timing of scan is crucial p 24
Liver
65
Equilibrium phase p 24
Density difference of less than 10 hu between abdominal aorta and inferior vena cava
Concentration in veins becomes similar to concentration in arteries
66
Hepatic arterial phase p 24
20-40 sec into injection
67
Portal venous phase p 24
60-90 s into injection
68
Liver injection phases p 24
Hepatic arterial phase
Portal venous phase
69
Opacification by oral contrast agents used? P 27
Reduce risk of misdiagnosing fluid filled bowel as abscess or tumor and helps visualize lesion is exterior to the bowel or if it infiltrates the bowel
70
Oral contrast media p 27
Barium sulfate
Iodinated
71
Barium used in ct vs conventional radiography ? P 29
Conventional barium too high density causing sever streak artifacts
72
Barium passes through gi tract without _____? P 29
Being absorbed or metabolized
73
Adverse reactions barium p 29
```
Diarrhea
Abdominal cramping
Barium granuloma
Barium appendicitis
Intestinal perforation
Peritonitis
```
74
Contraindications of barium p 30
Colon obstruction
Tracheosopageal fistula
Obstructing lesions of small intestine
Pyloric stenosis
Hypersensitivity to barium sulfate
75
Barium passes gi tract? P 30
Less than 2 hours
76
Iodinated oral contrast are more ____ than iv agent
Diluted
77
When to use iodinated oral agents vs barium? P 30
When contraindicated
78
How long Iodinated oral contrast passes through gi ? P 31
2 hrs
79
Post myelographic ct p 34
Elevate head
Confirm density of contrast media
Ensure contrast media does not separate from csf
80
Intraarticuar exam p 35
Injected into patient joint under fluro
81
Contrast for head exams p 36
Amount?
Delay?
No?
Dose 100 ml
Scan delay up to 5 mins after injection
No oral contrast
82
Normally enhanced during contrast ct of the head ? P 36
Blood vessels
Choroid plexus
Dura
83
Non contrast studies of head show ? P 37
Sininutis, trauma bleed, Graves' disease, early cerebrovascular events, early subdural hematoma, hydrocephalus, dementia, mastoiditis, labyrinthisis, facial or seventh nerve palsy, hearing loss, perteous and temporal bone
84
Contrast for neck ct pg 37
Amount
Injection rate
Delay
No?
Dose 100 ml
Injection rate 3 ml / sec
Scan delay 35 sec
No oral contrast
85
Ct neck with contrast allows differentiation of ? P 37
Blood vessels from lymph nodes and outline epidural venous plexus
86
Studies used for ct neck with contrast p 38
```
Neck mass
Lymph nodes
Parathyroid adenoma
Paratoid gland mass
Oral pharynx
Larynx
Brachial plexus
```
87
Contrast for chest exam p 38
Dose
Rate
Delay
Dose 100 ml
Injection rate 3 ml/sec
Scan delay 30 sec
No oral contrast
88
Studies of abdomen require both ____ ? P 39
Oral and iv contrast
89
Oral contrast abdomen ct helps ? P 39
Opacity gi tract helps decrease risk of mistaking fluid filled bowel for tumor or abscess
90
Ct abdomen with contrastrSt shows? P 39
Mass
Lesions
Vascular abnormalities
Trauma
91
Contrast for abdominal exams p 40
Dose 75-150 ml
Injection rate 2-4 ml/s
Scan delay
Liver: 70-80 sec
Pancreas: 50-60 sec
Kidneys: 80-90 sec
Oral contrast used
92
Biphasic liver study p 41
Used to perform differentiate liver lesions with arterial blood supply And those with venous blood supply
93
Cta study used for ? P 43
Evaluation of arteries and vessels
94
Why a cta exam? P 43
Narrowing by atherosclerosis
Anuerysms
Dissections
Traumatic injury
Congenital vascular anomolies
Effects of vascular treatment
95
Cta injection rate ? P 44
3-5 ml/sec
96
For cta exam, thin slices collected _______ direction of blood flow ? P 44
Same direction
97
Cta exams increasing the _____ scans vessels faster p 45
Pitch
98
Reconstruction of slices in cta p 45
With overlap which increases resolution
