IV Contrast Media & Dyes

Question 1

What are 3 osmotic Effects of IV contrast

Answer 1

Decrease in RBF
Decreased GFR
Osmotically-induced diuresis (dehydrating effect)

Question 2

3 classifications of ICM reactions

Answer 2

Idiosyncratic
Nonidiosyncratic
Contrast-induced nephropathy (CIN)

Question 3

Characteristics of Idiosyncratic Reactions

Answer 3

W/in 20min
Anaphylacatoid
Common in previous ICM reaction, asthma, food/drug/environ. allergy

Question 4

Symptoms of Idiosyncratic reactions

Answer 4

hives
n/v
diaphoresis
laryngeal edema
bronchospasm
HTN/HOTN
tachy/brady
seizures

Question 5

Nonidiosyncratic reactions may be _____ and should not be used in _______

the symptoms resemble _________

Answer 5

delayed; in pregnancy (nonionic agent preferred)

flu-like

Question 6

Nonidiosyncratic cardiovascular effects

Answer 6

negative inotrope
vasovagal
may precipitate angina
syncope
vasodilation
HOTN
lower threshold for V-arrhythmia
risk for cardiac arrest

hyperosmolar IVF w/ICM may cause HTN & pulm edema

Question 7

other nonidiosyncratic reactions include

Answer 7

extravasation
seizure
exacerbate other diseases

Question 8

contrast-induced nephropathy causes

Answer 8

> 50% elevation in creatinine
renal vasoconstriction
increased 02 free radicals
increased blood viscosity & O2 consumption

Question 9

what elevates the risk of CIN

Answer 9

pre-existing renal insufficiency
DM
CHF IV
Elderly
NSAIDS
Repeated doses
sepsis
anemia
hypovolemia

Question 10

what class of medicationos can help with contrast reactions

Answer 10

histamine blockers, IVF (NS, LR)

Question 11

What medications can help with a CIN reaction

Answer 11

N-acetylcysteine
Theophylline
Sodium Bicarb

Question 12

in management of CIN, it is not recommended to hold______ or ____

BUT______&______ should be avoided

Answer 12

routine diuretics or ACEI

mannitol & furosemide

Question 13

How to prevent contrast s/e

Answer 13

corticosteroids, H-2 blockers (pepcid, famotidine_, H-1 blocker (diphenhydramine)

Question 14

Indocyanine green (ICG) absorption and emission is ____ and should be reconstituted with_______

Answer 14

800-850nm

sterile water(unstable in aqueous solutions)

Question 15

Dose of Iindocyanine Green

Answer 15

Adults 5mg
Peds 2.5mg
MAX 2mg/kg

Question 16

Indigo Carmine absorption and excitation is ______
with a dose of

Answer 16

MAX 615nm
5mL

Question 17

Indigo Carmine may cause

Answer 17

Alpha adrenergic stimulation (transient HTN)

Question 18

Methylene Blue absorption and excitation peaks at______ and is incompatible with_____

Answer 18

700nm
normal saline

Question 19

Methylene Blue is a pregnaancy category_____ and should be avoided in patients with_______

Answer 19

X
G6PD deficiency, hepatic/renal impairment/antidepressant drugs

Question 20

Methylene blue is used to treat______(ferrous state) and can combine to ______to form cyanmethemoglobin

Answer 20

methemoglobinemia; cyanide

Question 21

methylene blue is sometimes used as a_________by inhibiting nitric oxide synthase and guanyl cyclase reducing formation of cGMP

Answer 21

vasopressor

Question 22

What is the dose of methylene blue

Answer 22

0.25-2mg/kg IV
infusion up to 3mg/kg/hr
administer slowly over 5-30min

Question 23

What are the adverse effects of methylene blue

Answer 23

MB is a potent MAOI(leading to fatal serotonin toxicity-HTN crisis)

Hemolysis
Hypersensitive reaction
HTN
Angina
Reduced mesenteric & cutaneous perfusion

Question 24

oxyhemoglobin absorbs more___
deoxyhemoglobin absorbs more______

Answer 24

more infrared 940nm

more red 660nm

Question 25

IV dyes w/lower absorption peaks decrease the absorption ratio of red & infrared wavelengths, giving a false

Answer 25

low oxygen saturation reading