CONTRAST MEDIA cttg 2009 notes

today : 

vic cttg sept 2009 1 today Explain some of the terms Look at safety What the manufacturers don’t tell you Whys and wherefores Update since RANZCR doc.

Why? : 

vic cttg sept 2009 2 Why? Because knowledge is power Because there is a lot of misunderstandings and misinformation out there RANZCR new guidelines We need to continuously look for any current evidence to improve practice We need to question information

Types : 

vic cttg sept 2009 3 Types X-ray attenuating Other- non X-ray attenuating

X-ray attenuating : 

vic cttg sept 2009 4 X-ray attenuating Iodinated Dissolved salt combinations Barium or non soluble

barium : 

vic cttg sept 2009 5 barium Safe- except for bowel perforation and pre surgical patients Inert No side effects No recorded allergies BARUIM

IODINE- ( I ) : 

vic cttg sept 2009 6 IODINE- ( I ) Discovered 1811 Named after lodes or violet Obtained from Na and K compounds Atomic number 53, 74 Neutrons 5 energy levels- 2, 8,18,18,7 Bentor, Yinon. Chemical Element.com - Iodine. May 31, 2009 <http://www.chemicalelements.com/elements/i.html>.

Slide 7: 

vic cttg sept 2009 7 The first 4 sections of the RANZCR guidelines deal with safety, Consent, reactions and treatment.

Slide 8: 

vic cttg sept 2009 8 A recent study in USA found that less the 50% of radiologists knew what to do in an emergency situation.

Slide 9: 

vic cttg sept 2009 9 So we all need to update our skills Check our drugs and uses Know which drug is for what Be able to supply useful help and information

Slide 10: 

vic cttg sept 2009 10 Because in an emergency situation the Radiologist is likely to be as stressed as you are 2 heads are better than one You are likely to see more reactions than they will

Iodinated : 

vic cttg sept 2009 11 Iodinated IONIC NON IONIC

Slide 12: 

vic cttg sept 2009 12 All currently used ICM are chemical modifications of a tri-iodinated benzene ring

IONIC v NON IONIC : 

vic cttg sept 2009 13 Difference is related to chemical engineering which affects its osmolarity IONIC v NON IONIC

Ionic ( Sodium Meglamine Diatrozoate, Ioxthalte)HIGH OSMOLAR : 

vic cttg sept 2009 14 Ionic ( Sodium Meglamine Diatrozoate, Ioxthalte)HIGH OSMOLAR

Sold as : 

vic cttg sept 2009 15 UROGRAFIN, CONRAY, ANGIOGRAFIN, TELEBRIX, RENAGRAFIN, UROVISON Still used today as base for oral contrast (Gastrografin, Gastroview, Isovue) Sold as

NON IONIC iopamidol, Iopamiro, Iopromide, IoversolISOVUE, OMNIPAQUE IPO OSMOLAR : 

vic cttg sept 2009 16 NON IONIC iopamidol, Iopamiro, Iopromide, IoversolISOVUE, OMNIPAQUE IPO OSMOLAR

ISO OSMOLAR iodixonalVisipaque : 

vic cttg sept 2009 17 ISO OSMOLAR iodixonalVisipaque

Why the focus on low osmolar ICM ( non ionic) when : 

vic cttg sept 2009 18 Why the focus on low osmolar ICM ( non ionic) when It is still CONTRAST MEDIA It is still nephro toxic It is still causing deaths

In other words “safety is a broader issue” and it is this that resulted in a very public court case.It is all about market share, reputation & : 

vic cttg sept 2009 19 In other words “safety is a broader issue” and it is this that resulted in a very public court case.It is all about market share, reputation &

$$$$$$$$$$$$$$$$$$$$$$$$$ : 

vic cttg sept 2009 20 $$$$$$$$$$$$$$$$$$$$$$$$$

The case : 

vic cttg sept 2009 21 The case It was that company A alleged in its advertising that its product was “safer”. Company B disputed this

Slide 22: 

vic cttg sept 2009 22 All low-osmolar contrast media (LOCM) produce the same rate of contrast-induced nephropathy. AAAAAAA is renally superior to all LOCM. AAAAAAA performs better than all LOCM because of lower osmolality and associated costs. AAAAA causes lower incidence of major adverse cardiac events (MACE) than all LOCM (although AA may claim, based on the VICC AAA vs. BBBB in Cardiac Catheterization] trial, that AAA causes less MACE than company B for patients undergoing percutaneous cardiac intervention within the initial 48 hours after the procedure). AAAA causes less discomfort than all LOCM.

Adverse incidents : 

vic cttg sept 2009 23 Adverse incidents CIN Allergic response Infection Pain Phlebitis Vomiting MACE Headaches, Chills, fever, sweating, headache, dizziness, blanching, weakness, gagging and a feeling of suffocation, gasping, a rise or fall of blood pressure, itching, urticaria, other kinds of skin eruption, oedema, cramp, tremor, syncope, sneezing and lacrimation.

Less severe Adverse Reaction : 

vic cttg sept 2009 24 Less severe Adverse Reaction Headaches Heat Pain Bruising at injection site Feeling of necessity to void Hypotension Hypertension Pseudo allergic skin rash Confusion dizziness

3 groups- AI or AR : 

vic cttg sept 2009 25 3 groups- AI or AR the hyper osmolar nature of IVCM the nephrotoxic effect Patient sensitivity

Osmolality : 

vic cttg sept 2009 26 Osmolality

Osmolality : 

vic cttg sept 2009 27 Osmolality

Osmolality : 

vic cttg sept 2009 28 Osmolality

OSMOLARITY RULES : 

vic cttg sept 2009 29 OSMOLARITY RULES The more similar that the injected substance is to the osmolality of blood then the less fluid shift across the cellular space

Slide 30: 

vic cttg sept 2009 30 290 mOsmol per kg of water Plasma Osmolarity

Osmolarity/Osmolality : 

vic cttg sept 2009 31 Osmolarity/Osmolality mOsm/L mOsm/kg All nonionic monomer contrast is hyper osmolar Non ionic is lower in osmolality than ionic Non-ionic dimers are the lowest on osmolality

Slide 32: 

vic cttg sept 2009 32 The osmolarity of IVCM solution ranges from 600 to 2100 mOsm/kg Osmolarity

ICM : 

vic cttg sept 2009 33 ICM Varies with concentration 150may be 320mOsmol per kg of water 300 -600mOsmol per kg of water 370- 774mOsmol per kg of water

ICM : 

vic cttg sept 2009 34 ICM So question whether a lower concentration may be adequate . And remember a lower kV may enable the use of a lower concentration For Paedriatric patients a lower concentration may be recommended anyway

Slide 35: 

vic cttg sept 2009 35 High osmolar- 2100- ionic monomer- nearly 10X Osmolarity

IONIC- high osmolarNON IONIC- low osmolar : 

vic cttg sept 2009 36 IONIC- high osmolarNON IONIC- low osmolar The more fluid that shifts, the greater the pain, the greater the heat sensation and the greater the risk of altering blood pressure resulting in a hypotensive crisis.

IONIC- high osmolarNON IONIC low osmolar : 

vic cttg sept 2009 37 IONIC- high osmolarNON IONIC low osmolar The greater the change of contrast density in the vessel or cavity- especially when patients are dehydrated!! Especially seen in oral contrast

Slide 38: 

vic cttg sept 2009 38 high, low or iso osmolar contrast. So why don’t we just talk about

Slide 39: 

vic cttg sept 2009 39 BUT it still wouldn’t make it any safer, or reduce the rate of CIN

Slide 40: 

vic cttg sept 2009 40 Common nonionic monomers are iohexol (Omnipaque; GE Healthcare, Inc), iopamidol (Isovue; Bracco Diagnostics Inc), ioversol (Optiray; tyco Healthcare and Mallinckrodt Inc), iopromide (Ultravist; Bayer HealthCare Pharmaceuticals Inc, Wayne, NJ). The nonionic monomers are the contrast agents of choice. nonionic monomers

Slide 41: 

vic cttg sept 2009 41 the lowest osmolality of all the contrast agents. At approximately 60% concentration by weight, these agents are iso-osmolar with plasma. They are also highly viscous (Visipaque; Amersham Health Inc, Princeton, NJ). Non Ionic dimers

Section 7- Renal Disease ALL IV CONTRAST IS NEPHTROTOXIC : 

vic cttg sept 2009 42 Section 7- Renal Disease ALL IV CONTRAST IS NEPHTROTOXIC These group of people have increased risk - over 60 ( 18% have a eGFR < 60) - sepsis - dehydration - vasculopaths ( all diabetics, Stroke, MI,) liver disease nephro toxic drugs - previous renal disease

Section 7- Renal Disease reduce the risk : 

vic cttg sept 2009 43 Section 7- Renal Disease reduce the risk Check renal function Hydrate ( DO NOT FAST FROM FLUIDS) Use patient questionnaires Take no risks- SEEK ADVICE Reduce IV contrast volume Use other imaging techniques that do no need IVCM

Chapter 8DIABETICS AND METFORMIN : 

vic cttg sept 2009 44 Chapter 8DIABETICS AND METFORMIN All diabetic patients are at risk for CIN if renal function is not adequate.

Adequate renal function : 

vic cttg sept 2009 45 Adequate renal function Estimated Glomerular Filtration Rate (eGFR) is a measure that combines Race Age Sex Serum Creatinin Creatinin alone is not adequate!

eGFR : 

vic cttg sept 2009 46 eGFR > 90 normal 20% of over 65y have less than 50% RF 60- 90 – renal damage an eGFR of <60 – moderate renal failure 30 -60 chronic renal disease (CKD) <15 end stage disease

Contrast induced nephropathy : 

vic cttg sept 2009 47 Contrast induced nephropathy The result of patients given a nephrotoxic drug when their renal function is impaired If renal function is normal then CIN is NOT an issue

Chapter 9 Pregnancy and IVCM : 

vic cttg sept 2009 48 Chapter 9 Pregnancy and IVCM There is no evidence that it is contra indicated but informed consent must be obtained

Allergic Contrast reactions : 

vic cttg sept 2009 49 Allergic Contrast reactions Acute- rare 1 in 170,000 will die 1 in 25,000 will react

Allergic Contrast reactions : 

vic cttg sept 2009 50 Allergic Contrast reactions Delayed Up to 7 days Usually minor

Allergic Contrast reactions : 

vic cttg sept 2009 51 Allergic Contrast reactions Patients with increased risks Previous reactions Multiple allergies SEA FOOD ALLERGY IS NOT ASSOCIATED WITH INCREASED RISK ALLERGY TO TOPICAL IODINE IS NOT A RISK FACTOR

Contrast extravasation : 

vic cttg sept 2009 52 Contrast extravasation Prevention is better Use appropriate vein and cannula for flow rate Use cannula and NOT scalp vein needles Flush adequately( 10mls saline is recommended by NSA) Visually monitor where possible

Flow rates ,PSI and cannula : 

vic cttg sept 2009 53 Flow rates ,PSI and cannula

Slide 54: 

vic cttg sept 2009 54 Copyright ©Radiological Society of North America, 2007 Wang, C. L. et al. Radiology 2007;243:80-87 Severe extravasation injury in an adult patient

Contrast extravasation : 

vic cttg sept 2009 55 Contrast extravasation Limb elevation Cold/warm compresses Monitor for compartment syndrome Surgical review if tissue damage is suspected

CHAPTER 10- Breast feedingThere is no evidence to support cessation of breast feeding. : 

vic cttg sept 2009 56 CHAPTER 10- Breast feedingThere is no evidence to support cessation of breast feeding.

: 

vic cttg sept 2009 57 CHAPTER 11- Thyroid disease IVCM – should not be administered to patients with hyperthyroidism or suspected thyroid CA having investigationsTFT- they may be inaccurate for 8 weeksThyroid isotope tests should be avoided for 8 weeks

Chapter 12. PhaeochromocytomasNo special precautions : 

vic cttg sept 2009 58 Chapter 12. PhaeochromocytomasNo special precautions

RISK MANAGEMNET : 

vic cttg sept 2009 59 RISK MANAGEMNET HAVE ESTABLISHED SAFE PROCEDURES AND PROTOCOLS OBSERVE THEM EVERY TIME QUESTION EVERYTHING

references : 

vic cttg sept 2009 60 references www.ranzcr.edu.au www.auntminnie.au www.druginformation.org.au Eur radiology 2006 16(5) 1041-9 Contrast Media Safety American Society of renal physicians Michael Bettman, Commonly asked Questions ,Iodinated Contrast Media, Radiographics 2004:24 S3-S10 MJA 2005- welcome to CKD and eGFR Wand et al Frequency Management and outcome of extravasations of non ionic contrast media. Radiology 2007 243: 8087 Jensen, Pharmacology and Drug Administration for Imaging Technologists. Mosby