Contrast media risk Flashcards
What are contrast media and what is their purpose?
Substances used to highlight areas of the body in radiographic contrast to their surrounding tissues
Help distinguish or “contrast” selected areas of the body from surrounding tissue
Improve visibility of organs, blood vessels or tissues to help diagnose medical conditions
Positive Contrast Media
High atomic mass = high attenuation
White
Radio-opaque
E.g Barium, Iodine based CM
Negative Contrast Media
Low atomic mass = low attenuation
Black
Radiolucent
Gas, CO2, water
Microbubbles
SonoVue
Optison
Definity
Ultrasound
Negative
Intravenous
Cystourethral
Vaginal
Microbubbles
SonoVue
Optison
Definity
Ultrasound
Negative
Intravenous
Cystourethral
Vaginal
Barium Sulphate
Readi-Cat
EZ-HD
EZ-Cat
Plain Radiography
Fluoroscopy
CT
Positive
Oral
Rectal
Barium Sulphate
Readi-Cat
EZ-HD
EZ-Cat
Plain Radiography
Fluoroscopy
CT
Positive
Oral
Rectal
Gadolinium
Dotarem
Magnevist
Gadevist
MRI
Positive
Intravenous
?Intraarterial
Intra-articular
Gadolinium
Dotarem
Magnevist
Gadevist
MRI
Positive
Intravenous
?Intraarterial
Intra-articular
Iodinated
Omnipaque
Niopam
Optiray
CT
Plain Radiography
Fluoroscopy
Theatre
Angiography
Positive
Intravenous
Intra-arterial
Oral
Rectal
Cystourethral
Vaginal
Intra-articular
Iodinated
Omnipaque
Niopam
Optiray
CT
Plain Radiography
Fluoroscopy
Theatre
Angiography
Positive
Intravenous
Intra-arterial
Oral
Rectal
Cystourethral
Vaginal
Intra-articular
Risks of contrast
Allergic Reaction / Anaphylaxis
CI-AKI Contrast Induced Acute Kidney Injury (Contrast media induced nephropathy)
PC-AKI Post Contrast Acute Kidney Injury (Acute Renal Failure)
Allergy/Anaphylaxis
severity
Sneezing
Itching
Rash
Hives
Swelling of face
Swelling/closure of airways
Dyspnoea/Apnoea
Cardiac Arrest
As soon as someone shows signs you should get crash cart ready in case it gets worse, also put a not on the system even if the patient is “fine” so if in future they have contrast its noted as usually the next time is worse
Acute Kidney Injuries information
AKI, commonly measured as a 25% increase in serum creatinine.
AKI is usually self limiting.
Risk of irreversible damage increases with increasing risk levels.
The definition of contrast nephropathy relies on serial plasma creatinine concentrations. A baseline creatinine level should be obtained before the procedure. Estimated glomerular filtration rate (eGFR) has been used for the assessment of renal function before intravenous contrast injection. This is calculated from the patient’s age, race, sex and serum creatinine level. Online calculators are also available to assist in easily calculating eGFR.
Some patient related risk factors for contrast media
Renal impairment with diabetes (High)
Renal Impairment without diabetes
Dehydration
Congestive heart disease
Old age
Concurrent administration of nephrotoxic drugs (such as metformin or ibuprofen)
Contrast media related risk factors of AKI
CM dose
Type of CM
Multiple administrations of CM
Intra arterial administration of contrast media
Reduce the risk of AKI? contrast media
Hydration
Discontinuing diuretics and giving saline hydration reduces CMIN by 50%. (Solomon).
Discontinue nephrotoxic medicines (for example Metformin withdrawal)
Use lowest dose consistent with good diagnostic quality
Always consider alternative imaging modalities
Good medical history
Lower kV = greater contrast
Good medical history for contrast media
History of contrast media examinations
History of diabetes
History of renal disease (check Creatinine level/eGFR)
History of asthma and/or breathing problems
History of anxiety
History of allergies
History of sickle cell anaemia
History of over-active thyroid