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Contrast media 2. CONTRAST MEDIA CHEMICAL PROPERTIES. TRIIODINATED COMPOUNDS BASED ON THE BENZOID ACID RING IODINE IS USED DUE TO THE HIGH ATOMIC NUMBER. IONIC CONTRAST. NON IONIC CONTRAST. CONTRAST MEDIA. Iodine Contrast Material. Non-Ionic Contrast Less patient allergic reactions.
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CONTRAST MEDIACHEMICAL PROPERTIES • TRIIODINATED COMPOUNDS • BASED ON THE BENZOID ACID RING • IODINE IS USED DUE TO THE HIGH ATOMIC NUMBER
IONIC CONTRAST NON IONIC CONTRAST CONTRAST MEDIA
Iodine Contrast Material • Non-Ionic Contrast • Less patient allergic reactions • Ionic Contrast • Anion - • Cation + • More patient allergic reactions • Ionic contrast media dissociates into two molecular particles in blood plasma = • Causing pt reactions
ANIONS - CHARGE IONS Responsible For Stabilizing And Detoxifying The Contrast Media CATIONS + CHARGED IONS Responsible For Increasing The Solubility Of The Medium Iodine Contrast Material
What contributes to discomfort, side effects, reactions: • VISCOSITY – (thick, sticky) thicker – harder to inject, more heat and vessel irritation (higher = greater viscosity) Warming contrast will help • TOXICITY - (higher = greater viscosity) • MISCIBILITY - easily mixes with blood
Iodinated CONTRAST AGENTSAdverse Reactions • Osmolarities higher than body fluids • Viscous • Greater chance for contrast reactions • Anaphylatic shock is the most severe
CONTRAST MATERIALADVERSE REACTIONS ALWAYS GET PATIENT’S HISTORY BEFORE ANY CONTRAST MEDIA IS GIVEN SEE Ch. 19 Table 19-7 pg 296 Carlton Pt Care (3RD ed)
General Factors for Contrast Reactions • Nonionic vs ionicRisk FactorsSeverity of ReactionsRenal toxicity • Glucophage Diabetic? • Screening Creatinine • Pretreatment
CONTRAST MEDIA & ADVERSE REACTIONS • RISK • Any foreign substance introduced in the body • Chance the body will react negatively to the material • Minor to Life Threatening Minor = 5% Major 0.1%
Kidney problems Diabetes Heart conditions Allergies Asthma Previous reaction Current medications Beta Blockers Antihypertensive medications VITAL SIGNS GOOD PATIENT HISTORY
CONTRAST REACTIONS • General • > 10 million diagnostic procedures per year • Conventional ionic contrast reactions - 10% • 1 in 1000 severe
Contraindiatons for Contrast • Renal Failure (Check BUN & Creatinine) Elevated levels could cause renal shutdown • Anuria (no urine production) • Asthma (possible allergies) • Hx of Contrast Allergy / Reactions • Diabetes - get a hx of medications taken • glucophage must be stopped 48 hrs before contrast injection • Multiple Myeloma
MORE Risk Factors for Contrast Reaction • Older patient age • Allergic Rhinitis, medication or Food Allergy • Cardiovascular disease
CONTRAINDICATIONS • Pregnancy (risk of fetal Thyroid toxicity) • + Radiation concerns • Allergic Reaction • Pathologic Conditions • Infection
Allergic to Iodine • General Rule: • No Iodine Contrast will be given • Pre – medication is available • May or may not react if previous iodine given
Aseptic Technique for injection betadine scrub Contains iodine
REACTIONS & Treatment USUALLY** WITHIN FIRST 5 MINUTES • Nausea & Vomiting & Urticaria • Hypotension (bradycardia) • Hypotension (tachycardia) • Bronchospasm • Anaphylactoid • Seizures • Extravasation
Catagories of Adverse ReactionsMILD Ch. 19 pg 297 Pt Care • nausea, vomiting • Uticaria (hives) rash – itching • Flush face – feeling of warmth • Headace, Chills, Anxiety • Diaphoresis Treatment – does not usually get worse Watch patient and reassure (cool cloth on forehead, emesis basin
Catagories of Adverse ReactionsMODERATE Ch. 19 pg 297 Pt Care • Hypotension (bradycardia) • Hypertension (tachycardia) • Dyspnea • Bronchospasms /wheezing • Laryngeal Edema TREATMENT: Needs immediate treatment –GET RN/RAD Needs Meds* – (Keep IV line in) could lead to severe reactions
Catagories of Adverse ReactionsSEVERE Ch. 19 pg 297 Pt Care • Laryngeal edema • Convulsions • Profound hypotension • Clincally manifested arrhythmias • Unresponsiveness • Cardiopulmonary Arrest PROMPT TREATMENT – CODE BLUE!
Rx for REACTIONShave ready on Emergency cart or Crash Cart • UTICARIA (HIVES) – Benadryl (diphenhydramine) Vistaril (hydorxyzine) Tagament or Zantac • Facial/Laryngeal Edema/Bronchospasms Epinephrine , Oxygen
Contrast Reactions/MYTHS • not caused by iodine • Ionic vs non ionic - binding elements • not related to shellfish • not true allergy (no drug-antibody) • mechanism remains unknown
Anaphylactoid (idiosyncratic) • unpredictable • dose independent • prevalence 1-2% (0.04 - 0.22% severe) • fatal 1 in 75,000
RENAL TOXICITY • (increased serum creatinine > 0.5 mg%) • 2-7% • 5 – 10 x increase with pre-existing renal insufficiency • direct relationship between serum creatinine and likelihood nephrotoxicity • Hydrate 100 ml/hr Normal saline 4 hrs prior to procedure, continue for 24 hours
GLUCOPHAGE • Pt is DIABETIC = oral diabetic agent • MUST STOP __ DAYS BEFORE EXAM • withhold drug for 48 hrs after contrast administration • patients with renal insufficiency may develop lactic acidosis • The signs of lactic acidosis are deep and rapid breathing, vomiting, and abdominal pain
PreMedications • Steroids (Prednisone) • Benadryl (diphenhydramine) • Epinephrine
EXTRAVASATION • Contrast material has seeped outside of vessel • Local redness and swelling • Apply WARM Compress 1st 24 hours • Cool compress for swelling
SCHEDULING CONSIDERATIONS • Diabetics – first • (Insulin= low blood sugar occurs while fasting) • After Nuclear Medicine Tests • (iodine goes to thyroid and will alter results) • Iodine BEFORE Barium • BE before UGI ( IVP before BE) • WATER – OIL - BARIUM
SPECIAL PROCEDURSCONTRAST MEDIA ARTHROGRAMS • Injected into JOINT SPACES • IODINE (positive contrast) • WATER soluble • (Ionic or Non-Ionic) • AIR (negavitve contrast)
SPECIAL PROCEDURSCONTRAST MEDIA MYELOGRAMS • Injected INTRATHECALLY (into the subarachnoid space) • Nonionicwater-soluble contrast • (NO IONIC CONTRAST)
31 y/o male DIESafter Myelogram Procedure • Myelography is safely performed using • nonionic water-soluble radiographic contrast media intended for this route of administration • Misadministration of ionic contrast media intrathecally can result in a syndrome of spasms and convulsions, often leading to death • ISOVUE –M ( 20 or 30 cc)
mix-up between look-alike vials • ionic HYPAQUE (diatrozoate meglumine) • nonionic OMNIPAQUE 300 (iohexol) • Each type of contrast media should be stored separately, based on its use.
SPECIAL PROCEDURSCONTRAST MEDIA SIALOGRAPHY – injected into Salivary Ducts • IODINE – • WATER (ionic or nonionic) • OR OIL BASED • SINOGRAPHIN (OIL) • RENOVUE (WATER)
PATIENT PREP COVERED WITH EACH EXAM
ONLY Watersol. Arthrograms Myelograms Angio/Arterio grams Cardiac Cath Venograms Water or OIL Hysterosalpingogram Sialogram Lymphangiograms Lasts longer – may cause FAT EMBOLI REVIEW SPECIAL PROCEDURSCONTRAST MEDIA