Dear Dr Slater RANZCR Draft Iodinated Contrast Guideline

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1 AUSTRALIAN AND NEW ZEALAND COLLEGE OF ANAESTHETISTS A.B.N January 2016 Dr Gregory Slater Dean, Faculty of Clinical Radiology Royal Australian and New Zealand College of Radiologists Level 9, 51 Druitt Street Sydney NSW Dear Dr Slater RE: RANZCR Draft Iodinated Contrast Guideline Thank you for the opportunity to comment on the RANZCR Draft Iodinated Contrast Guideline, 2016 Edition. As you may be aware, the Australian and New Zealand College of Anaesthetists (ANZCA), which includes the Faculty of Pain Medicine (FPM), is responsible for the education, training and continuing professional development of specialist anaesthetists and specialist pain medicine physicians, as well as the accreditation of hospitals where specialist training takes place. ANZCA commends the Working Group on the robust review process undertaken to produce the updated document and the decision to produce the final guideline in a number of formats to enhance implementation. Whilst we reviewed the entire document our comments pertain mostly to the sections dealing with reactions to iodinated contrast media. We sought the expert input of the Anaesthesia Allergy Subcommittee of the ANZCA Safety and Quality Committee, whose membership includes both anaesthetists and immunologists. The main issues identified relate to the terminology used to describe hypersensitivity reactions to iodinated contrast media and the practical management of such reactions. Use of the term anaphylactoid The term anaphylactoid should be avoided for the following reasons: 1. According to Nomenclature Review Committee of the World Allergy Organization 1, anaphylaxis should be the umbrella term for an acute reaction that is defined as a severe, life-threatening generalised or systemic hypersensitivity reaction. Anaphylaxis is then further classified as allergic anaphylaxis versus non-allergic anaphylaxis. Anaphylactoid is the equivalent of the latter terminology. Accordingly, European Academy of Allergology and Clinical Immunology (EAACI) discourages the term anaphylactoid to describe non-ige mediated reactions. 2,3 ANZCA HOUSE 630 ST KILDA ROAD MELBOURNE VIC 3004 AUSTRALIA TELEPHONE FACSIMILE

2 2. Anaphylaxis and anaphylactoid reactions are often clinically indistinguishable and their immediate management is identical. However, the term anaphylactoid can sometimes have the false connation that it is less severe. 3. The term anaphylactoid assumes that the mechanism is non-ige mediated. This may have been the case for older ionic contrast media. However, there is emerging evidence that shows a sizable portion of immediate reaction to non-ionic contrast media is IgE mediated. 4 Therefore it is incorrect to assume that all immediate reactions are non-ige mediated. 4. The term delayed anaphylactoid contrast reactions (in 2.2) is confusing. Anaphylactoid is an acute reaction whereas maculopapular rash is not an acute reaction. Most delayed reactions do not involve typical immune mechanisms involved in anaphylaxis. Delayed reactions to contract reactions are often T cell mediated. 5,6 Deciding what should be the best alternative terms in the context of this guideline is difficult but following the International Consensus on drug allergy 3, it is suggested to use: 2.1. Immediate Hypersensitivity Reaction (including Anaphylaxis) to Iodinated Contrast Media OR 2.1 Anaphylaxis to Iodinated Contrast Media AND 2.2. Non-immediate Hypersensitivity Reaction to Iodinated Contrast Media Another example: For 1.8 d) & e) more accurate wording would be treatment of immediate hypersensitivity reactions or simply treatment of anaphylaxis. We acknowledge that changing the language to avoid using anaphylactoid throughout the guideline will necessitate considerable editing. Management of anaphylaxis to iodinated contrast As the guideline is likely to be used by staff not primarily skilled in crisis management, consideration should be given to simplification of the protocol for management of hypersensitivity. There should be emphasis on calling for critical care help early, particularly in freestanding facilities. A suggested regimen for treatment of a hypersensitivity reaction in a radiology suite, based on the Australasian Society of Clinical Immunology and Allergy (ASCIA) Guidelines for Acute Management of Anaphylaxis 7, is included as Appendix 1. We would recommend that this be used to simplify section 4 and the wall chart. It includes a clarification of paediatric doses. ASCIA recommends that only oral non-sedating antihistamines should be used to treat skin reactions and thus we suggest that the reference to intramuscular antihistamines be removed. This will address the noted discrepancies in the table (section 4) and the wall chart (pg. 43 of 46): under mild reactions the table suggests considering oral or intramuscular antihistamines whereas the wall chart mentions oral or IV antihistamines. The published ASCIA Guidelines for Acute Management of Anaphylaxis are included as Appendix 2 to this submission. The have been recently updated (2015) and are the Page 2 of 6

3 recommended guideline for anaphylaxis management outside the operating theatre. They apply to severe hypersensitivity reactions. General comments Other comments pertaining to specific sections of the RANZCR guidelines are as follows: Background New data indicates that some reactions to iodinated contrast do involve IgE antibodies. This implies that skin testing may have a role for the diagnosis and management. The distinction between IgE mediated anaphylaxis versus non-ige mediated anaphylaxis (or non-allergic anaphylaxis) cannot be made clinically. The authors of the guideline have identified a low incidence of severe reactions and this is validated by Brockow et al Emergency Equipment In addition to airways and bag and mask devices, intubating equipment is recommended for when skilled assistance arrives. As with an automated external defibrillator, such equipment needs to be kept in working order and thus regularly checked. For mild cutaneous reactions, non-sedating antihistamines would be preferable as promethazine can be sedating. Hydrocortisone is mentioned in the guideline but is not included in the list of medications. 4.1 Confirmation of Anaphylactoid Reaction Consideration may be given to referral of patients to allergy services for further assessment with skin testing. Whilst there is lack of convincing data on the use of skin tests to select contrast media that can be safely given, the study by Caimmi et al 9 suggests that the negative predictive value of intradermal skin tests was high at 97%. Patients should be provided with the exact name of the contrast used after the reaction and prompted to consider providing this detail in a MediAlert bracelet. It is hoped that the above comments are of use in facilitating the publication of contemporary evidence based guidelines. Further expert advice on the area of management of hypersensitivity reactions can be sought from ASCIA directly. Yours sincerely Dr Phillipa Hore Chair, Safety and Quality Committee Australian and New Zealand College of Anaesthetists Page 3 of 6

4 References 1. Johansson SG, Bieber T, Dahl R, et al. Revised nomenclature for allergy for global use: Report of the Nomenclature Review Committee of the World Allergy Organization, October J Allergy Clin Immunol 2004;113: Lee JK, Vadas P. Anaphylaxis: mechanisms and management. Clin Exp Allergy 2011;41: Demoly P, Adkinson NF, Brockow K, et al. International Consensus on drug allergy. Allergy 2014;69: Brockow K, Ring J. Anaphylaxis to radiographic contrast media. Curr Opin Allergy Clin Immunol 2011;11: Kanny G, Pichler W, Morisset M, et al. T cell-mediated reactions to iodinated contrast media: evaluation by skin and lymphocyte activation tests. J Allergy Clin Immunol 2005;115: Keller M, Lerch M, Britschgi M, et al. Processing-dependent and -independent pathways for recognition of iodinated contrast media by specific human T cells. Clin Exp Allergy 2010;40: Australasian Society of Clinical Immunology and Allergy. Acute Management of Anaphylaxis Guidelines. Balgowlah NSW Brockow K, Christiansen C, Kanny G, et al. Management of hypersensitivity reactions to iodinated contrast media. Allergy 2005;60: Caimmi S, Benyahia B, Suau D, et al. Clinical value of negative skin tests to iodinated contrast media. Clin Exp Allergy 2010;40: Page 4 of 6

5 APPENDIX 1 Recommended Treatment Regimen for Management of Anaphylaxis in a Radiology Suite Mild: nausea/vomiting and skin reaction only Stop administration of contrast Provide supportive measures Closely observe for any changes suggestive of moderate reaction Use only oral non sedating antihistamines to treat skin reactions Moderate: hypotension, bronchospasm or breathing difficulties +/- skin reaction Stop administration of contrast Call for help/ambulance O2 via mask 6-10L/min Lay patient flat unless breathing difficulties, then allow to sit. Use IM adrenaline dosage chart from ASCIA document (See below) Closely observe for any changes suggestive of severe reaction Repeat IM adrenaline 5 minutely as needed Special Circumstances: Add the Following Therapy Upper airway obstruction Nebulised adrenaline 5 ml i.e. 5 ampoules of 1:1000 Call for airway management expertise (Anaesthesia/MICA/Critical Care physician) Hypotension Elevate the legs Normal saline 20 ml/kg initially Bronchospasm Children Salbutamol (Metered dose inhaler, MDI) < 6 years 6 X 100 mcg puffs MDI, or mg nebulised > 6 years 12 X 100 mcg puffs MDI or 5 mg nebulised Adults Salbutamol 12 X 100 mcg puffs or 5 mg nebulised Page 5 of 6

6 Severe: life threatening hypotension, bronchospasm or airway obstruction Stop administration of contrast Call for help/ambulance Oxygen via mask 6-10l/min Lay patient flat unless breathing difficulties Commence CPR if required at any stage Use IM adrenaline dosage chart from ASCIA document (See below) Repeat IM adrenaline 5 minutely as needed Seek emergency medicine/critical care specialist advice Special Circumstances: Add the Following Therapy Upper airway obstruction Nebulised adrenaline 5 ml i.e. 5 ampoules of 1:1000 Call for airway management expertise (Anaesthesia/MICA/Critical Care physician) Persistent hypotension Elevate the legs Normal saline 20 ml/kg initially and repeat up to 50 ml/kg in first 30 minutes If patient on beta blockers consider 1-2 mg of glucagon IV (Adult dose) Persistent wheeze Children Salbutamol (Metered dose inhaler, MDI) < 6 years 6 X 100 mcg puffs MDI, or mg nebulised > 6 years 12 X 100 mcg puffs MDI or 5 mg nebulised Adults Salbutamol 12 X 100 mcg puffs or 5 mg nebulized IV hydrocortisone 5 mg/kg to maximum of 200 mg References Australasian Society of Clinical Immunology and Allergy. Acute Management of Anaphylaxis Guidelines. Balgowlah NSW From: Accessed 5 January O Meara M & Watton DJ. Advanced Paediatric Life Support: The Practical Approach. Appendix J Formulary. 5th [Australian] ed Blackwell, West Sussex. Page 6 of 6

7 Appendix 2 - ANZCA response re draft RANZCR guideline Acute management of anaphylaxis guidelines These guidelines are intended for primary care physicians and nurses providing first responder emergency care. Immediate action 1. Remove allergen (if still present). 2. Call for assistance. 3. Lay patient flat. Do not allow them to stand or walk. If breathing is difficult, allow them to sit. 4. Give INTRAMUSCULAR INJECTION (IMI) OF ADRENALINE without delay using an adrenaline autoinjector if available OR adrenaline ampoules and syringe. 1:1000 IMI into outer mid-thigh 0.01mg per kg up to 0.5mg per dose Repeat every 5 minutes as needed. If multiple doses required or a severe reaction consider adrenaline infusion if skills and equipment available. 5. Call ambulance to transport patient if not already in a hospital setting. If required at any time, commence cardiopulmonary resuscitation. Supportive management (when skills and equipment available) Check pulse, blood pressure, ECG, pulse oximetry, conscious state. Give high flow oxygen if available and airway support if needed. Obtain IV access in adults and hypotensive children. If hypotensive, give IV normal saline 20mL/kg rapidly and consider additional wide bore IV access. Disclaimer: ASCIA information is reviewed by ASCIA members and represents the available published literature at the time of review. The content of this document is not intended to replace professional medical advice and any questions regarding a medical diagnosis or treatment should be directed to a medical practitioner. ASCIA 2015.

8 Appendix 2 - ANZCA response re draft RANZCR guideline ASCIA Guidelines: Acute Management of Anaphylaxis 2015 Additional measures - IV adrenaline infusion in clinical setting If inadequate response or deterioration start IV adrenaline infusion, given by staff who are trained in its use or in liaison with an emergency/critical care specialist. Mix 1 ml of 1:1000 adrenaline in 1000 ml of normal saline. Start infusion at 5 ml/kg/hour (~0.1 µg/kg/minute). Titrate rate up or down according to response. Monitor continuously. IV adrenaline infusions should be used with a dedicated line, infusion pump and anti-reflux valves wherever possible. CAUTION: IV boluses of adrenaline are NOT recommended without specialised training as they may increase the risk of cardiac arrhythmia. Additional measures to consider if IV adrenaline infusion is ineffective For Upper airway obstruction For persistent hypotension/shock For persistent wheeze Nebulised adrenaline (5mL i.e. 5 ampoules of 1:1000). Consider intubation if skills and equipment are available Give normal saline (maximum of 50mL/kg in first 30 minutes). Glucagon (1-2mg IMI or IV as starting dose) especially for patients on beta blockers or has heart failure. In adults, selective vasoconstrictors metaraminol (2-10mg) or vasopressin (10-40 units) only after advice from an emergency medicine/critical care specialist. Bronchodilators: Salbutamol 8-12 puffs of 100µg using a spacer OR 5mg salbutamol by nebuliser. Note: Bronchodilators do not prevent or relieve upper airway obstruction, hypotension or shock Corticosteroids: Oral prednisolone 1 mg/kg (maximum of 50 mg) or intravenous hydrocortisone 5 mg/kg (maximum of 200 mg). Note: Steroids must not be used as a first line medication in place of adrenaline. Antihistamines and corticosteroids Antihistamines: Antihistamines have no role in treating or preventing respiratory or cardiovascular symptoms of anaphylaxis. Do not use oral sedating antihistamines as side effects (drowsiness or lethargy) may mimic some signs of anaphylaxis. Injectable promethazine should not be used in anaphylaxis as it can worsen hypotension and cause muscle necrosis. 2

9 Appendix 2 - ANZCA response re draft RANZCR guideline ASCIA Guidelines: Acute Management of Anaphylaxis 2015 Corticosteroids: The benefit of corticosteroids in anaphylaxis is unproven. It is common practice to prescribe a 2-day course of oral steroids (e.g. oral prednisolone 1 mg/kg, maximum 50 mg daily) to hopefully reduce the risk of symptom recurrence after a severe reaction or a reaction with marked or persistent wheeze. Observe patient for at least 4 hours after last dose of adrenaline Relapse, protracted and/or biphasic reactions may occur. Patients will require overnight observation if they: Had a severe or protracted anaphylaxis (e.g. required repeated doses of adrenaline or IV fluid resuscitation), OR Have a history of asthma or severe/protracted anaphylaxis, OR Have other concomitant illness (e.g. asthma, history or arrhythmia), OR Live alone or are remote from medical care, OR Present for medical care late in the evening. The true incidence of biphasic reactions is estimated to occur following 3-20% of anaphylactic reactions. Follow up treatment Adrenaline autoinjector If there is a risk of re-exposure (e.g. stings, foods, unknown cause) then prescribe an adrenaline autoinjector before discharge, pending specialist review. Train the patient in autoinjector use and give them an ASCIA Action Plan for Anaphylaxis (see ASCIA website Allergy specialist referral Refer ALL patients who present with anaphylaxis for specialist review The allergy specialist will: - Identify/confirm cause. - Educate regarding avoidance/prevention strategies, management of comorbidities. - Provide ASCIA Action Plan for Anaphylaxis - preparation for future reactions. - Initiate immunotherapy where available (some insect venoms). Documentation of episodes Patients should be advised to document the circumstances of episodes of anaphylaxis to facilitate identification of avoidable causes (e.g. food, medication, herbal remedies, bites and stings, co-factors like exercise) in the 6-8 hours preceding the onset of symptoms. The ASCIA anaphylaxis event record can be used to collect this information ( Preparation: Equipment required for acute management of anaphylaxis The equipment on your emergency trolley should include: Adrenaline 1:1000 (consider adrenaline autoinjector availability in rural locations for initial administration by nursing staff) 1ml syringes; 21 gauge needles Oxygen Airway equipment, including nebuliser and suction Defibrillator Manual blood pressure cuff IV access equipment (including large bore cannulae) Pressure sleeve (aids rapid infusion of fluid under pressure) At least 3 litres of normal saline 3

10 Appendix 2 - ANZCA response re draft RANZCR guideline ASCIA Guidelines: Acute Management of Anaphylaxis 2015 A wall chart has been developed for use by health professionals and published in Australian Prescriber (August 2011). ASCIA 2015 The Australasian Society of Clinical Immunology and Allergy (ASCIA) is the peak professional body of clinical immunology and allergy specialist in Australia and New Zealand. Website: projects@allergy.org.au Postal address: PO Box 450 Balgowlah NSW Australia 2093 Disclaimer This document has been developed and peer reviewed by ASCIA members and is based on expert opinion and the available published literature at the time of review. Information contained in this document is not intended to replace medical advice and any questions regarding a medical diagnosis or treatment should be directed to a medical practitioner. The development of this document is not funded by any commercial sources and is not influenced by commercial organisations. 4