CT Contrast

Question 1

Where is contrast used

Answer 1

SBRT - small volume delineation

Question 2

NSQH standard 4

Answer 2

• process for documentating patient history of medicine allergies and adverse drug reactions
• process for documentating adverse drug reactions experienced by patients during an episode of care
• Process for reporting adverse drug reactions experienced by patients to the therapeutic goods administration

Question 3

What should happen in emergency situations

Answer 3

Check for early warning signs
Recognise problem and trigger response
Initiate action (communicate, CPR, address danger) and call for help
Assist when help arrives

Question 4

IV contrast usefulness

Answer 4

Assists in tumour localisation
Specially in the abdomen as it also enhances soft tissue visualisation

Question 5

Phases of contrast enhancement

Answer 5

Depends on pathology of interest
Some lesions can be hypovascular or hyper vascular compared to normal tissue

Peripheral IV injection - travels to right side of the heart, pulmonary circulation and left heart before reaching the central arterial system which travels to the rest of the organs .

Question 6

Timing of arterial phase

Answer 6

35-40sec
Arteries will show optimal enhancement

Question 7

Timing of hepatic or portal phase

Answer 7

70-80sec
Enhancement of portal and hepatic veins

Question 8

Hepatic phase

Answer 8

Liver tissue is highlighted

Question 9

Contrast flow rate

Answer 9

Depends on volume of contrast
Patient weight
Rate of flow of the volume fo the contrast
SI unit is ml/sec
Large volume administered = faster flow rate

Question 10

Patient ineligibility criteria

Answer 10

Known allergy to contrast
Abnormal renal function
Diabetes managed with metformin

Question 11

Types of adverse reactions

Answer 11

Anaphylactic, chemotoxic (organ specific), Vasovagal

Question 12

Anaphylactoid

Answer 12

Mild - nasal congestion, sneezing, pruritis
Moderate - wheezing, dyspnoea, hypertension
Severe - arrhythmia, cardiac arrest, anaphylaxis

Question 13

Chemotoxic

Answer 13

Nephrotoxicity, neurotoxicity, cariotoxicity

Question 14

Patient risk factors

Answer 14

Congestive heart failure
Nephrotic syndrome
Dehydration
Multiple myeloma
Asthma
Hyperthyroidism
Pregnancy
Extremely anxious

Question 15

Extravasating

Answer 15

Leakage of an intravenous drug from the vein into surrounding tissue
Very rare - small risk of injury is extravasating are greater than 100ml
Can cause swelling, tenderness.
Severe compartment syndrome, necrosis

Question 16

What to do in case of extravasation

Answer 16

Immediate treatment
Remove cannula
Stop infusion
Elevate affected extremity
Apply hot pack with towel

Question 17

Useful sites for contrast use

Answer 17

Lung
Oesophagus
Mediastinal nodes
Liver
Pancreas
Metastatic brain lesions

Question 18

Types of contrast in CT

Answer 18

Iodine based non-ionic chemical
Pre-loaded syringes 100-125mL
Kept it in 37 degrees to maintain viscosity
Intravenous administration
Type - Omnipaque

Question 19

Where does contrast excrete through

Answer 19

Renal route

Question 20

Radiation oncologist role

Answer 20

Discuss CT planning site with planner
Contrast enhancement phases requested
Discuss cannualtion site with planner
Attach tubing to cannula
Start pressure injector
Monitor patient
Disconnect tubing from cannula
Flush line

Question 21

RANZCR training guidelines

Answer 21

• trained in the recognition of contrast media reactions and procedures for treating these reactions and resuscitation procedures

Question 22

Role of RNs

Answer 22

Remind patient about H2O
Renal function test complete
Resuscitation equipment
Patient education
Remove cannula 20min post contrast

Question 23

CT simulation protocol

Answer 23

1st scan is planning data set
2nd scan is contrast data set

Question 24

Mild, Moderate and Severe Contrast Reactions

Answer 24

Mild:
* flushing, nausea, pruritus, vomiting, headache and mild urticaria
* usually self-limited and resolve without specific treatment

Moderate:
* severe vomiting, marked urticaria, bronchospasm or other respiratory symptoms

Severe:
* hypovolaemic shock, respiratory arrest, cardiac arrest and convulsions
* very rare