Anaphylaxis Flashcards
Define Anaphylaxis
Acute allergic reaction
Life threatening airway obstruction and/or breathing and/or circulation -> shock
diagnosis is always clinical-not long enough for tests
aetiology and risk factors for Anaphylaxis
its a general hypersensitivity reactions-allergy to an allergen
1/3 caused by food allergies
IgE mediated
CAn also be non IgE mediated-rarer
Shock is caused by:
Depress HR directly
Vasodilation
Fluid leaks from vessels-
airway block-
leaked fluid causes swelling
altered SMC tone in bronchus
Risk factors
Food-Usually younger people
COPD/Asthma-increase threat to life
PMH of Anaphalysis
Women
Epdiemology of Anaphylaxis
Probably under reported
on the rise in recent years, but still only a few hundred a year
food more common for young
medicine more common for old
Signs and symptoms of anaphylaxis
ACUTE ONSET-very fast Airway--angiooedema (swelling on neck/tongue) Inspiratory STRIDOR and hoarse voice Feeling dizzy Feeling like impending doom SOB, Wheezing Cyanosis, Pale, clammy Skin Tachycardia (or Brady)
Skin changes are often the first to come-urticaria, rashes, erythema
=>itchy, red, D&V, sweaty
Investigations of anaphylaxis
DONT HAVE TIME
can do mast cell tryptase during ressuc maybe
ECG-ST CHANGES post crisis are common
Management of Anaphylaxis
Secure airway and remove cause
EPINEPHRINE (Epipen)
acts of a2 receptors to constrict vessels
Acts of B2 to help HR
acts on B1 to relax airways
If cardiac arrest-CPR and ressuss –
If no arrest- ABCDE approach, Adrenaline
Give O2, Iv fluids
SABA
Atropine
after acute management-give antihistamines, steroids
Complications of anaphylaxis
Death by resp arrest into cardiac arrest
MI-not to common but happens
Reccurence is a risk
Prognostic for anaphylaxis
500-1000 cases per year that end in death
quite common and bad if not recognised immediately
