Guidelines Regarding the Use of Intravenous Contrast Media

Royal Brompton & Harefield NHS Trust Guidelines regarding the use of Intravenous Contrast Media

TRUST POLICY

IMAGING DEPARTMENT

INTRAVENOUS CANULATION AND ADMINISTRATION OF INTRAVENOUS CONTRAST MEDIUM

GUIDELINES FOR RADIOGRAPHERS & RADIOLOGISTS

Authors: Bradley Park, Deputy Imaging Services Manager, RBH

Trupti Patel, CT Superintendent Radiographer, HH

Dr. Tarun K. Mittal, Lead Clinician & Consultant Radiologist, HH

Approved by:…………………………………………………………………..

Drugs & Therapeutics Committee, RBHT,

Implemented by:…………………………………………………………………

Prof. D.M.Hansell, Director of Imaging, RBH

…………………………………………………gist……………….

Dr. Andrew Kelion, Director of Imaging, HH

Issue Date: Jan2013

Review Interval:2 years

SUMMARY OF THE DOCUMENT

This guideline deals with intravenous cannulation and administration of intravenous (IV) contrast medium by Radiographers for CT Scanning and Intravenous Urography in Imaging Departments throughout the Trust.

TIMETABLE

The authorised guidelines will be distributed to all relevant clinical areas in paper format and posted on the Trust Intranet – Policies and Guidelines/Policies and Procedures/Patient Related

Dissemination:

Imaging Department, RoyalBromptonHospital
Imaging Department, HarefieldHospital

Review:2 years

ASSOICATED DOCUMENTS

Patient Group Directive for Intravenous or Intra-arterial Administration of Radiographic Contrast Media

CONTENTS

1.The Purpose of Guideline

2.The Imaging Process

3.Patient information and consent

4. Practical safety issues

5.Identifying patients at increased risk for contrast reaction

5.1History of previous contrast reaction

5.2Asthma

5.3Multiple allergies or a documented severe allergy requiring therapy

5.4Renal disease, diabetes mellitus and conditions associated with renal impairment

5.5Metformin

6.Other special cases

7.Eligibility of radiographers for intravenous cannulation, administration of iodinated contrast media and general procedural guidelines

8.Procedure for intravenous cannulation and administration of intravenous contrast media by radiographers

9.Management of adverse reactions to contrast medium (for all radiographers)

10.Guidelines following extravasation of contrast medium

11.References

Appendix 1 - Estimated GFR

Appendix 2 - Metformin patient information letter

Appendix 3 - Extravasation patient information letter

Appendix 4 - Management of adverse reactions

Appendix 5 - Cannulation Equipment Guidelines

Appendix 6 - Check-list prior to adminstration of intravenous contrast medium

1.THE PURPOSE OF GUIDELINE

The use of iodinated intravascular contrast agents (hereby referred to as ICM) has increased dramatically in recent years in all aspects of imaging as they provide valuable diagnostic information. However they are not without side effects and thus the potential risks of intravascular administration of contrast media must be weighed against the potential benefits. At the same time, withholding agents may deprive patients of the benefits of valuable diagnostic information or necessary therapy.

This guideline aims to ensure that :

Overall safety of the patient is maintained in the process of intravenous administration of ICM.

Patients who are at increased risk of contrast reactions are identified as early as possible, so that adequate measures can be taken prior to the examination.

Radiographers undertaking Intravenous cannulation and administration of ICM are adequately trained and familiar with the procedures required to perform the ICM administration safely.

All radiographers are familiar with management of reactions to ICM.

The ultimate responsibility for the administration of contrast medium rests with the supervising radiologist, although the delivery of the injection is frequently delegated to radiographers.

The introduction of low osmolar non-ionic contrast has reduced the frequency of reactions to contrast medium, but there are higher than average risk groups that radiographers must be aware of.

This guideline deals with administration of contrast medium to adult patients. For children and neonates, the supervising radiologist should be consulted.

2. THE IMAGING PROCESS

2.1The CT scan process

2.1.1All CT scan requests must be protocoled by the supervising radiologist with a written instruction (on the request form) if contrast media is required for the CT scan.

2.1.2The contrast media should be injected following a written protocol, unless otherwise directed by supervising radiologist.

2.1.3All radiographers in CT scanning must check with each patient for known allergies or risks.

2.1.4All cannulating radiographers must adhere to cannulating procedure.

2.1.5All radiographers in CT scanning should be aware of risks entailed in the injection of contrast medium and know how to manage them appropriately.

2.2Intravenous Urography (IVU)

2.2.1This procedure is much less commonly performed in the Trust and always involves the use of ICM.

2.2.2The same process, as for CT scanning should be followed.
3.PATIENT INFORMATION AND CONSENT

Patients should always be fully informed about the CT scanning procedure and understand what it will involve. For out-patients this has to be done by enclosing the appropriate patient information leaflet with the appointment letter. Besides, the leaflets are to be made available to the patients in the CT waiting area. In all cases (both in and out-patients), the radiographer who administers the contrast medium and/ or performs the procedure must explain the procedure to the patient and go through the questions to identify risks that patient may have pertaining to contrast administration if it is to be administered. Ideally the risks should have been identified earlier by procedures outlined in section 5, and appropriate action taken before the patient comes for the scan.

The radiographer must still ensure that the patient understands the procedure, risks have been identified and appropriate action taken and agrees verbally to proceed. This is documented on the reverse side of the Trust’s Imaging request form.

4.PRACTICAL SAFETY ISSUES

Two members of staff should be present in the scanning suite, if possible, when a radiographer is cannulating and injecting contrast.

In the event of a severe contrast reaction, staff on duty should have should have the knowledge to seek urgent medical help by contacting the Cardiac Arrest Team.

In presence of risk factors, the decision about contrast agent administration should be taken only by the radiologist supervising the procedure.

In view of the risk of contrast nephrotoxicity, dehydration of patients prior to contrast agent administration is undesirable and should be avoided.

Facilities for treatment of acute adverse reactions should be readily available and regularly checked.

A patient should not be left alone or unsupervised for the first 5 minutes after injection of the contrast agent.

It is advisable that the patient remains within the Imaging (or CT) Department for, at least, 15 minutes after the injection. Most severe reactions occur during this time. In patients at increased risk of a reaction, this should be increased to 30 minutes.

All contrast reactions, with details of their nature, severity, and the agent used, should be included in the radiological report and updated in the patient’s record.

IDENTIFYING PATIENTS AT INCREASED RISK FOR CONTRAST REACTION

The followingessential information should be sought from the referring clinician / patient before the contrast injection includes:

Previous contrast reaction
Asthma
Renal problems
Diabetics on Metformin therapy
Patients who are dehydrated or in congestive heart failure are at higher risk of contrast induced renal failure.

However, the Imaging departments must make all possible efforts to ensure that this information is available when the examination is requested in the following manner:

A: For elective out-patient procedures:

By ensuring that the necessary fields relating to above risk factors are adequately filled by the referring clinician for examinations where contrast may be required.
Through patient information leaflets and appointment letter in which they are informed of the possibility of injection of an intravenous contrast (dye) and asked to ring up the Imaging department in advance if they are aware of having any of the above risk factors.
Recent eGFR (performed within last 2 months) must be available as per 5.4.3

For non-emergency in-patient procedures:

By making sure that the necessary parts relating to above risk factors are adequately filled by the referring clinician for examinations where contrast may be required.
Recent eGFR (performed most recent during the current admission) or Serum Creatinine (if eGFR not available) must be available as per 5.4.3

For emergency in-patient procedures:

In these cases the potential benefits of using contrast agents must be weighed against the potential risks. In these cases the ICM injectionshould be followed by a generous saline flush (40-50mls) and post-procedural hydration as in 5.4.6, if patient has no contra-indication.

If any risk factor is identified by the above process, appropriate measures should be taken as per the local procedures described below and if necessary the supervising radiologist should be consulted.

The level of information provided on the request forms will be monitored and regularly audited.

5.1 History of previous contrast reaction

5.1.1Caution should be exercised when there is a previously reported moderately severe (e.g. bronchospasm or uticaria requiring treatment) or a severe reaction (e.g. laryngeal or angioneurotic oedema, severe bronchospasm or collapse).

5.1.2Determine the exact nature of the previous reaction and what agent used on that occasion.

5.1.3The supervising radiologist must assess the risk/benefit of the procedure.

5.1.4If administration of contrast is deemed necessary:

use a different (non-ionic low or iso-osmolar) agent to that previously used
maintain close medical supervision
leave the cannula in place and keep the patient under observation for 30 minutes
and be ready to treat promptly any adverse reaction and ensure that emergency drugs and equipment are available

5.1.5Pre-treatment with steroids should be considered only after consultation with the supervising radiologist and the referring clinician.

5.2Asthma

5.2.1Asthmatics are at an increased risk of severe contrast reactions by a factor of 6 with low osmolar non-ionic contrast media and by a factor of 10 with high osmolar agents.

5.2.2Determine whether the patient has true asthma or COPD, and whether the asthma is currently well controlled.

5.2.3If the patient is wheezy or reports that their asthma is currently not well controlled and the CT scan is not urgent, it should be deferred and the patient referred back for appropriate medical therapy.

5.2.4The supervising radiologist must reassess to decide whether to undertake the CT scan with contrast medium.

5.2.5If administration of contrast is deemed necessary:

use a non-ionic low or iso-osmolar agent
maintain close medical supervision
leave the cannula in place and keep the patient under observation for 30 minutes
and be ready to treat promptly any adverse reaction and ensure that emergency drugs and equipment are available

5.3Multiple allergies or a documented severe allergy requiring therapy

5.3.1Individuals with multiple, well documented allergies or a single very severe allergy are at increased risk.

5.3.2There is no conclusive evidence of benefit for the prophylactic use of steroids in the prevention of severe reactions to contrast medium.

5.3.3Determine the nature of the allergies and their sensitivity (N.B. there is no specific cross reactivity with shellfish or topical iodine in acute reactions).

5.3.4In patients with multiple or severe allergy, the supervising radiologist must reassess the need for contrast administration.

5.3.5If administration of contrast is deemed necessary:

use a non-ionic low or iso-osmolar agent
maintain close medical supervision
leave the cannula in place and keep the patient under observation for 30 minutes
and be ready to treat promptly any adverse reaction and ensure that emergency drugs and equipment are available

5.4 Renal disease, diabetes mellitus and conditions associated with renal

impairment

5.4.1In patients with renal impairment, all contrast agents, including non-ionic low osmolarand iso-osmolar agents are nephrotoxic.

5.4.2The risk of contrast nephrotoxicity is related to the extent of pre-existing renal impairment, the dose of contrast agent administered and the state of hydration of the patient. Congestive heart failure, over the age of 70 years old and concurrent administration of nephrotoxic drugs are also risk factors for contrast nephrotoxicity.

5.4.3A recent eGFR(performed within last 2 months for out-patients and most recent during the current admission for in-patients)should be available for all patients with a history of renal disease or diabetes. A level of <60 mL/min/1.73m2 for eGFR (see Appendix 1 for more information) and >120 micromoles per litre for serum creatinine has been used in the literature to indicate renal impairment. Patients with an eGFR level of <40mL/min/1.73m2 should be considered to have severe renal impairment.

5.4.4If available a portable blood testing unit should be used if a recent serum creatinine or eGFR is not available. The creatinine result from this test should be converted to an eGFR using the renal association accepted calculator.

5.4.5The supervising radiologist must reassess to decide whether to undertake the CT scan with contrast medium.

5.4.6The referring clinician should be notified of the risks of contrast medium nephrotoxicity before the examination is carried out.

5.4.7If administration of contrast is deemed necessary:

Stop administration of nephrotoxic drugs for at least 24 hours if possible.

The patient should be adequately hydrated. Give at least 100mls/hour orally (e.g. soft drinks) or intravenously (normal saline or dextrose/saline) depending on the clinical situation, from 4 hours before to 24 hours after contrast administration (but IV saline may not be possible in heart failure). In case of in-patients these instructions should be communicated to the referring doctor and/ or staff nurse. Out-patients should be given oral instructions for oral intake of sufficient fluids if not in heart failure. In patients where this volume cannot be administered safely (e.g. heart failure), less vigorous hydration may provide some protection.

Use the smallest possible dose of low osmolar non-ionic monomeric or iso-osmolar non-ionic dimeric contrast medium (Visipaque).

5.4.8For intra-venous administration of ICM, there is insufficient evidence at this stage to advocate the prophylactic administration of N-acetylcysteine in patients at high risk for contrast nephrotoxicity. However, for catheter lab procedures see Trust ‘Guidelines and protocol for the prevention of contrast nephropathy following the use of iodinated radiographic contrast media – Adult Cardiology’.

Risk Factors for Contrast Induced Nephropathy

NSAIDs, Cyclosporin A, Tacrolimus / Pre-existing Renal Disease/ impairment
Aminoglycosides, Amphotericin / Peripheral Vascular Disease
Age > 70 / Diuretic use, especially furosemide
Diabetes mellitus / Hypertension
Contrast load in last 72hrs / Hyperuricaemia or hypercholesterolaemia
Congestive Cardiac Failure / Multiple myeloma

5.5 Metformin

5.5.1Metformin is not recommended for use in diabetics with renal impairment because it is exclusively excreted via the kidneys, if excretion is prevented this can result in lactic acidosis.

5.5.2The use of Metformin should not be considered an issue when the decision is made to administer IV contrast to a patient. As with all patients the renal function should be examined and used as an indication of whether the patient is suitable for IV contrast.

5.5.3The discontinuing of Metformin should only be considered in patients with renal impairment, as defined in section 5.4.3, and only after Consultation with the referring clinic.

6.Other special cases

6.1Pregnancy: In exceptional circumstances, iodinated contrast may be administered during pregnancy. Because of the small theoretical risk of thyroid suppression in the foetus, thyroid function should be measured in the first week after birth.

6.2Lactation: A very small percentage of the injected dose enters the breast milk and virtually none is absorbed across the normal gut and no special precaution or cessation of breastfeeding is required.

6.3 Thyroid: Intravascular contrast should not be administered if the patient is

hyperthyroid. In patients with thyroid cancer, the use of iodinated contrast

agents will preclude therapeutic radio-iodine treatment for 2 months. MRI is

the preferred staging method in these patients.

6.4Interleukin-2 treatment: A specific risk of delayed skin rash is associated with Interleukin-2 therapy. Oncologists should be informed that they should always indicate if the patient is on this drug when referring them for a contrast injection.

7.Eligibility of Radiographers for Intravenous Cannulation, iodinated

contrast administration and general procedural guidelines

7.1The cannulating radiographer will have been formally approved and certified by Departmental Clinical Director / Lead Clinician for IV cannulation. He or she should have completed an intravenous cannulation certificate course and should be able to demonstrate and maintain regular competency.

7.2All eligible radiographers should be familiar with procedures and guidelines regarding management of reactions to intravenous contrast media as in sections 9, 10 and Appendix 4.

7.3The cannulating radiographer must follow the Procedure for Injecting of Intravenous Contrast Medium as outlined in section 8.

7.4Radiographers must inject only non-ionic contrast (they are not certified to inject other materials).

7.5The radiographer should not cannulate in the following circumstances:

Paediatric patients (aged 15 years and below).
Patients with a previous allergic reaction
Out of hours

7.6The radiographers will regularly audit their work, assessing first time accuracy for injections, number of extravasations and number of contrast medium reactions.

7.7 The cannulating radiographer should complete Intermediate Life Support

Course, as well as the Basic Life Support Course, annually.

8.Procedure for Intravenous Cannulation and Administration of Intravenous Contrast Media by radiographer

8.1Patient ID and clinical details must be carefully checked by the radiographer as per hospital identification policy.

8.2The radiographer should introduce themselves by name and professional title.

8.3An explanation of the CT scan should be given to patient, including the reason for the intravenous injection.

8.4 Two members of staff should be present in the scanning suite, if possible,

when a radiographer is cannulating and injecting contrast.

8.5The patient must be questioned for known allergies. The checklist prior to administration of Intravenous Contrast flow diagram (see Appendix 6) should be used and documented on the reverse of the Imaging request form.

8.6The Infection Control – Hand Hygiene Policy must be adhered to throughout the procedure.

8.7The radiographer should select an appropriate vein in the ante-cubital fossa or dorsum of the hand and introduce a cannula into the vein and secure it. The cannula should be flushed with saline (5-10 mls) to check for proper positioning and any extravasation. Cannulation Equipment Guidelines (Appendix 5) should be followed.