Contrast Media Part 2 (RADS 210)

Pre-contrast history for a contrast study

look for any contradictions (blockage, ulcer), medications, pregnancy, prior surgeries (scarring will show up), revies laboratory results

-mandatory

Informed Consent

All patients must be advised of adverse reactions to contrast media particularly IVU

-must sign before injection of an iodinated contrast media

Informed consent indicates that the phsycian or designee has had a conversation with the patient regarding:

-purpose of procedure

-how procedure is to be performed

-possible risks/complications

-consequences of not having the procedure

Contradictions to iodinated CM

-previous reaction to contrast

-asthma

-allergies

-heart disease

-renal disease

-diabetic medications (glucophange & metformin, must be off these meds the day before and 2 days after)

Side Effect

reaction in a manner that is of little or no consequence, nature of the drug we are ingesting (flushed feeling, metallic taste)

Adverse Effect

reactions that are more toxic, need some level of intervention or will lead to death (rash, difficulty breathing)

-idiosyncratic reactions (BAD)

Vasovagal

reaction from high anxiety rather than from contrast media

Four categories of reactions based on systems affected:

Cutaneous/Gi (nausea, hives, flush)

Respiratory (bronchospasm, respiratory arrest)

Cardiovascular (hypotension, pale, arrhythmias)

Neurological (not seen alot with CM, syncope, shock)

mild reaction to contrast media

pt observed for 20 minutes to ensure no further reactions as it is not life threatning

-nausea, cough, warmth, headache, dizziness, hives

Greatest incidence of occurence for mild reactions to CM occurs in pts.

30-50yrs

Lowest incidence of occurence for mild reactions to CM occurs in pts.

over 65 years of age and in the very young

Treatment for mild reactions to CM

observation, reassure pt, antihistamines for dermal reactions

Moderate reaction to CM

more pronounced but not immediately life threatening, close observation as it can move to severe, may require medical attention and be given dipenhydramine for bronchospasms and leg elevation for hypotension

-brochospasm, hyper or hypotension, tachy or brachycardia, dyspnea

Severe reaction to CM

life threatning with more severe signs and symptoms, requiring immediate treatment, rarely occur

-convulsions, arrhythmias, unresponsiveness, cardiopulmonary arrest

Histamine Imbalance accounts for mostly the...

mild classification of contrast media reactions

Histamines

normally found in the body and are released from the blood plasma to the body tissue, whenever tissue injury occurs

When the body comes in contact with a certain substance to which it is sensitive...

an excess of histamines arereleased causing a reaction

The release/stimulation of histamines causes:

-production of gastric juices

-dilation of capilaries

-contriction of smooth muscle

Systemic Shock

blood pressure drops and there is inadequate blood supply to tissue; can lead to cardiac arrest

Myocardial Infarction (MI)

heart attack; damaged red blood cells cause lack of oxygen so the heart tissue dies (no blood flow to heart)

Renal Shutdown

damaged red blood cells will not fit through nephron, so kidneys do not recieve proper nutrients, resulting in the shut down of the kidneys

How to recognize histamine imbalance

pt gets red and itchy can be relieved by taking antihistamine

How to recognize hemodynamic response

pt becomes disoriented and becomes pale from lack of blood flow

Iodinated Contrast Media Injection can send a patient into:

Anaphylactic Shock

Anaphylactic

hypersensitivity reaction resulting from injection (or exposure to) of a substance to whcih an individual has become sensitized

Early Symptoms of Anaphylactic Shock

tightness in chest, itching at injection site, nasal congestion, coughing sneezing, nausea, vomiting

Later Symptoms of Anaphylactic Shock

urticaria, edema, decrased blood pressure, dilated pupils, change in LOC

Prognosis for Anaphylactic Shock

death if emergency treatment is not given

Treatment for Anaphylactic Shock

epinephrine, corticosteroids, O2, artificial respiration

When refferering to CM never use the word...

dye, it is contrast media

All contrast media is approved by the...

FDA but nothing is 100% safe

In the case of a reaction to CM..

call phsyciian immediately as reactions may be immediate (0-5 minutes) after injectionn or delayed so never leave pt alone

Order for scheduling contrast media procedures:

- elderly or debilitated pts.

- diabetic pts.

- children

-adults (can last longer w/o eating or drinking)