CT Contrast

Question 1

What is its imaging application?

Answer 1

• diagnostic CT
• MRI
• PET
• 4DCT

Question 2

What is contrast media?

Answer 2

• radiopaque substances
• administered during medical imaging
• enahnce visualisation of organs

Question 3

What is IV contrast media?

Answer 3

• administered intravenously
• injected through vein, flows through bloodstream, travels through arteries and viens
• enhances soft tissue deliniation

Question 4

What are the phases of contrast media?

Answer 4

• arterial phase: 35-40 seconds shows arteries
• hepatic/portal phase: 70-80 secs shows hepatic and portal veins
• brain: 5 mins due to blood brain barrier

Question 5

What is the contrast flow rate?

Answer 5

• dependent on volume of contrast administered
• patient weight increases = increased contrast = increased flow rate
• unit for flow is mL/sec

Question 6

What are the ineligibility criteria?

Answer 6

• known allergy to contrast
• abnormal renal function (renal function assessed at least 1 month prior to planning)
• diabetes managed with metformin (need to be off this for 2 weeks prior to contrast)

Question 7

What are some patient risk factors?

Answer 7

• congestive heart failure
• nephrotic syndrome
• dehydration
• multiple myeloma
• asthma
• hyperthyroidism
• myasthenia gravis
• sickle cell anaemia
• polycythemia and myeloma
• extremely anxious patients
• pregnancy/breast feeding

Question 8

What is the post contrast allergies?

Answer 8

• dizziness
• nausea/vomitting
• itching/hives
• abdominal pains/muscle cramps
• anaphylactic reaction

Question 9

What is extravasation?

Answer 9

• is the leakage of an intravenous drug from the vein into the surrounding tissue
• incident rate of 0.1-0.4%

Question 10

What is the immediate treatment of extravasation?

Answer 10

• stop infusion and aspirate and revome cannula
• elevate effected extremity above heart
• apply hot pack wih towel

Question 11

How can you precent extravasation?

Answer 11

• flush the line with saline prior to injection of contrast

Question 12

What site ustilise contrast?

Answer 12

• lung
• oesophagus
• mediastinal nodes
• liver
• pancreas
• metastatic brain lesion

Question 13

Why is contrast kept at 37 degrees?

Answer 13

• as it can turn viscous which doesnt inject well

Question 14

What is the type of intravenous contrast?

Answer 14

• iodine based non-ionic chemical
• OPTIRAY 350 pre-loaded syringes (100mL or 125mL)
• single barrel injector system

Question 15

What are the risks and precautions with contrast?

Answer 15

• drug reactions: resuscitation trolley and adrenaline shot kept close
• staff trained and equipped: all basic life support, RO advanced life support
• multidisciplancy approach to preparation
• managment to pre and post procedure

Question 16

What is the role of the RO?

Answer 16

1. initial consent
   - renal function test
   - patient educaiton
   - allergies
   - consent for procedure
   - discussion of cannula site with planner
2. CT SIM
   - attach cannula
   - start pressure injector
   - monitor patient
   - disconnect tubbing
   - flush line with saline

Question 17

What is the role of the nurse?

Answer 17

• remind patient to be well hydrated
• renal function test complete
• resusitiaiton equipment
• patient education
• remove cannula 20mins post CT

Question 18

What is the role of the RT?

Answer 18

• ensure incubator is one and set to 37
• contrast is in incubator
• reconrd contrast expiry date
• record contrast lot number
• recoard aomunt mL
• record on assesment form
• set flow rate on injector as per protocol