Primary care emergencies - Anaphylaxis
In the third of our six-part series on common emergencies in primary care, GPs Dr Chantal Simon, Dr Karen O’Reilly, Dr Robin Proctor and Dr John Buckmaster guide you through how to deal with anaphylaxis
In the third of our six-part series on common emergencies in primary care, GPs Dr Chantal Simon, Dr Karen O'Reilly, Dr Robin Proctor and Dr John Buckmaster guide you through how to deal with anaphylaxis
Common causes of an anaphylactic attack are:
•food allergies: nuts, fish and shellfish, sesame seeds and oil, milk, eggs, pulses (beans, peas)
•insect stings: wasp or bee
•drugs: antibiotics, aspirin and other NSAIDs, opiates
Look out for one or both of the following:
•respiratory difficulty, such as wheeze, stridor – may be due to laryngeal oedema or asthma
•hypotension, which can present as fainting, collapse or loss of consciousness.
An anaphylactic attack may cause all or some of the following:
•itching of palate
•itching of external auditory meatus
•sense of impending doom.
•airway – mouth and tongue for oedema
•breathing – chest (wheeze), PEFR
•circulation – pulse, blood pressure
•skin – rashes.
See the note at end of this article for accessing algorithms for management of anaphylaxis and the box for action to take.
•Warn patients or parents of the possibility of recurrence.
•Advise sufferers to wear a device (such as a MedicAlert bracelet) that will inform
bystanders or medical staff should a future attack occur.
•Refer all patients after their first anaphylactic attack to a specialist allergy clinic.
•Consider supplying sufferers (or parents) with an Epipen or similar that can be used to administer IM epinephrine (adrenaline) immediately should symptoms recur.
•If you supply an Epipen, teach anyone likely to need to use it how to operate the device. Intramuscular epinephrine is very safe.
Quality points are available for practices that possess the equipment and in-date emergency drugs to treat anaphylaxis (Medicines Indicator 2).
This is an extract from Emergencies in Primary Care published by Oxford University Press, edited by Dr Chantal Simon, a GP in Dorset and MRC health service research fellow at the department of primary medical care, Southampton University Medical School,
Dr Karen O'Reilly, a GP in Hampshire, Dr Robin Proctor, a GP in Surrey, and Dr John Buckmaster, a GP in the Outer Hebrides. See www.oup.co.uk ISBN 978-0-19-857068-4 or click on the link on the right of the screen
To access useful algorithms on treating adults and children go to www.resus.org.uk and go to the A-Z index on the main index page. Click on ‘anaphylactic reactions – treatment for adults by first medical responders' or ‘anaphylactic reactions – treatment for children by first medical responders'.
• If anaphylaxis is suspected when the initial call for help comes in, call an ambulance immediately, then visit.
• When the initial call is taken, ask if the patient has had a similar event before. If so, ask if they have an Epipen or similar. If they have, advise the caller to use it immediately.
• Ensure patient is comfortable – lie down flat, with leg elevation if BP is decreased; sit up if difficulty breathing
• If available, give oxygen at high flow rates
• Give IM adrenaline (epinephrine) to all patients with clinical signs of shock, airways swelling, or breathing difficulty.
– adult or child over 12 years: 0.5ml epinephrine (adrenaline) 1:1000 solution (500µg) IM.
Give half dose if: prepubertal or adult on tricyclic antidepressants, monoamine oxidase inhibitors or ß-blockers
– child six to 12 years: half adult dose – 0.25ml
of 1:1000 epinephrine (adrenaline) solution (250µg) IM
– child six months to six years: quarter adult
dose – 0.12 ml of 1:1000 epinephrine (adrenaline) solution (120µg) IM
– child less than six months: 0.05ml 1:1000 epinephrine (adrenaline) solution (50µg) IM.
Absolute accuracy of dose is not necessary.
• Repeat after five minutes if improvement is transient, no improvement or deterioration after initial treatment. May need several doses.
• Give an antihistamine.
Dose of chlorphenamine:
– adults and children over 12 years: 10-20mg IM
– children six to 12 years: 5-10mg IM
– children one to six years: 2.5-5mg IM
• Give hydrocortisone by IM or slow IV injection.
– adults and children over 12 years: 100-500mg
– children six to 11 years: 100mg
– children one to five years: 50mg
– children under one year: 25mg
• Give salbutamol if bronchospasm.
• If severe hypotension does not respond rapidly, start an IV infusion (if available) and rapidly infuse 1-2l of saline until BP increases (children 20ml/kg rapidly then another similar dose if not responding).
• Admit the patient to hospital until ill effects have settled.
Note: The preferred site for an IM injection is the midpoint of the anterolateral thigh