Download Anaphylaxis

Anaphylaxis
Alex Pearce-Smith
Scenario
• A patient who is well but has been called
in for a medication review has just sat
down. Suddenly the practice nurse bursts
in and announces that a patient to whom
she has just vaccinated seems to be
having a severe reaction.
In Groups/Pairs Think About….
• What do you do initially?
• What is your assessment?
• What are the signs of anaphylaxis?
Assessment
• Excuse yourself from patient – go straight to sick patient
and assess - ?help ABCDE.
• Severe/Life threatening features in anaphylaxis.
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A Swelling, Hoarseness, Stridor.
B RR, Wheeze, Sats <92%.
C Pale, clammy, Low BP.
D Confused/Drowsy/Coma.
Recognising Anaphylaxis
• Anaphylaxis likely when ALL 3 criteria met
•
1. Sudden onset and rapidly progressing
symptoms.
2. Life threatening
Airway/Breathing/Circulatory problems.
3. Skin/Mucosal changes (angio-oedema,
flushing or urticaria)
PMH and circumstances may help (ie given
vaccine).
Skin Changes
• Usually first feature but may be absent in upto 20% of
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cases.
May be subtle or dramatic.
May be just skin, just mucosal or both.
Maybe patchy or generalised erythematous rash.
May be urticaria – usually itchy.
Angioedema is similar to urticaria but affects the deeper
tissues – usually eyelids and lips but sometimes mouth
and throat.
Not an indicator of severity – most systemic skin
reactions do not end up as anaphylaxis.
Skin Presentations
Differential Diagnoses
• Vasovagal attack.
• Panic attack.
• Idiopathic urticaria.
• Breath-holding episode in a child.
Management
• ABC assessment indicates severe/lifethreatening.
– Lie flat, feet up*.
– Remove trigger (e.g. bee sting).
– IM adrenaline 0.5mg adult (over 12) less for
children/babies.
– Oxygen.
– Fluid Challenge (crystalloid).
– Chloramphenamine and hydrocortisone.
– Some should be calling 999.
Management
• Should go to hospital for further
management/observation – 6hrs minimum
but most discharged by 24 hrs if good
response.
• Various indicators for longer observation.
• Review by senior clinician before
discharge.
• Specialist follow up in allergy clinic.
Common Triggers
• Food (especially nuts)
• Drugs
– Antibiotics esp penicillin and cephalosporin
– Anaesthetic drugs
– Other drugs esp NSAIDs.
• Venom – esp wasp stings.
Mortality
• Less than 1% mortality.
• About 20 deaths per year in UK recorded due to
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anaphylaxis but may be underestimate.
Asthmatics more at risk.
Deaths happen quickly after contact with
allergen.
– Food 30 mins.
– Venom 15 mins.
– IV medications 5 mins.
In conclusion
• If severe or life-threatening symptoms and
clinical suspicion of anaphylaxis – give
adrenaline.
• Remember ABC – you may not get beyond A.
For More Information
• For details about the recommended recognition
and management of anaphylaxis including
correct paediatric dosages etc go to
Resuscitation Council Website.
• http://www.resus.org.uk/pages/reaction.pdf