ANAPHYLATIC SHOCK Flashcards
etiology of anaphylactic shock ?
food majority of the time
peanuts , eggs , fish , shell fish , strawberries
drugs - penicillin , NSAIDs, opioids
bee / wasp sting
what is non-allergic anaphylaxis ?
non-ige mediated mast cell activation
non immunological anaphylaxis
similar presentation and management
what causes non-allergic anaphylaxis ?
contrast
vancomycin
opioids
anesthesia
what are the clinical manifestation of anaphylaxis?
low BP , HR
patients with a systolic blood pressure (SBP)<90 mmHg
MAP < 65 mm Hg or a decrease of 40 mm Hg from baseline
tachycardia
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respiratory - shortness of breath cyanosis stridor - DUE TO LARYNGEAL EDEMA wheezing due to bronchospasm
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angioedema of the eyes and lips and hands and feet
skin - itch and sweating , erythema
GI - diarrhea , vomiting
what is the onset features of anaphylactic shock ?
onset seconds or minutes post exposure
5-20 percent have a biphasic reaction with recurrence of symptoms in the following 12hrs
diagnosis of anaphylactic shock ?
rapid onset plus one of the 3 criteria
1) skin/ mucosa symptom + cardiac and respiratory compromise
2) exposure to likely allergen for patient + 2 or more organ system affected (skin/mucosa , GI , cradiac)
3) exposure to known allergen for patient and low blood pressure
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serum tryptase
- marker of mast cell granulation peaking after 1hr - remains elevated for 6hrs
does not aid incase diagnosis
what is the management of anaphylaxis ?
1)secure the airway
give 100 percent oxygen!
intubate
2) remove cause if still present
raise the feet - might help circulation
3) Adrenaline 0.5mg IM in middle , anterolateral thigh
is children <6 150mcg (0.15ml )
>6-12 300mcg
ratio of 1:1000
1g per 1000ml
0.5ml
repeat every 5 mins
if refectory switch to IV infusion
Refractory to IV epinephrine infusion
Administer IV glucagon , especially if the patient is on a beta blocker
Consider combination with other vasopressors: e.g., vasopressin, norepinephrine, dopamine, and phenylephrine.
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4) IV access and give fluids - 2L crystalloid
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5) further drugs
chlorophenamine 10mg IV reduces itch and hives
hydrocortisone 200mg IV amy reduce prolonged biphasic reactions
neither actually treated anaphylaxis and not much evidence to support it
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6) continued wheeze , treate as you would asthma
salbutamol
what should be warned on discharge ?
warn them about biphasic reaction
avoid potential triggers
give 2 preloaded 300mcg adrenaline auto injectors as interim until referred to allergy clinic
