Anaphylaxis Flashcards
Define anaphylaxis.
Severe, acute, life-threatening multi system reaction to an allergen
What are the early features of anaphylaxis?
Throat/tongue swelling
Hoarseness
Wheeze
Rash
What are the late features of anaphylaxis?
Stridor
Shallow breathing
Cyanosis
Confusion (due to hypoxia)
Hypotension
Summarise the management of anaphylaxis.
What are the ABC symptoms of anaphylaxis?
Airway - swelling, hoarseness, stridor
Breathing - rapid breathing, wheeze, fatigue, cyanosis, SpO2 < 92%, confusion
Circulation - pale, clammy, low BP, faintness, drowsy/coma.
What are the doses of adrenaline given to different age groups?
< 6yo = 150mcg
6-12 yrs = 300mcg
> 12yrs and adults = 500mcg
ALL IM.
What fluid challenge should you give to adults and children in anaphylaxis?
Adults - 500-1000ml
Child - 20ml/kg
What type of fluids may cause anaphylaxis?
Colloid (these contains proteins or starches that attach water)
What doses of chlorphenamine and hydrocortisone can be given to adults in allergic reactions?
Chlorphenamine: IM/slow IV 10mg
Hydrocortisone IM/slow IV 200mg
(always 20 times higher dose of hydrocortisone than chlorphenamine except in <6mo)
What doses of chlorphenamine and hydrocortisone can be given to children 6-12yo in allergic reactions?
Chlorphenamine: IM/slow IV 5mg
Hydrocortisone IM/slow IV 100mg
(always 20 times higher dose of hydrocortisone than chlorphenamine except in <6mo)
What doses of chlorphenamine and hydrocortisone can be given to children <6yo in allergic reactions?
Chlorphenamine: IM/slow IV 2.5mg
Hydrocortisone IM/slow IV 50mg
(always 20 times higher dose of hydrocortisone than chlorphenamine except in <6mo)
What is the dose and dilution of adrenaline used in anaphylaxis?
1:1000
0.5mls IM
Repeat after 5min if no response
Also give 200mg hydrocortisone and 10mg chlorphenamine
What investigations should be done in anaphylaxis?
Mast cell tryptase - initially thwn 1-2hrs later (should be <1ng/ml but will rise to >100ng/ml in anaphylaxis)
How long do you monitor after anaphylaxis?
6-12hrs to monitor for a biphasic reaction
What is the management TTA after anaphylaxis?
Prednisolone 40mg for 3-5days
Antihistamine
Discharge with 2 EPIPENS and counsel on how to use these
GP to refer urgently to allergy/immunology clinic for further work up