acute asthma Flashcards
what are some common asthma triggers?
viral infection, allergens, smoking, exercise, stress, bacteria infection
what are some features of the airway in an asthma attack?
eosinophils infiltrate blood vessels, contracted smooth muscle, decreased lumen diameter, excess mucus
what is a sign of a life threatening exacerbation?
drowsy, confused silent chest hypoxic then hypercapnic cyanosis bradycardia hypotension peak flow under 20% expected no response to bronchodilator
what are some signs of a severe exacerbation?
talks in words hunched forwards agitated resp rate over 30/min accessory muscles used pulse rate over 120 bpm O2 sats under 90% peak flow less than 50% expected/best
what are some signs of a mild or moderate exacerbation?
talks in phrases prefers sitting to lying increased resp rate accessory muscles not used pulse 100-120 bpm O2 sats 90-95% peak flow over 50% expected/best
how are asthma exacerbations treated?
SABA
prednisolone
oxygen
oral corticosteroids (glucocorticoids)
if severe: add ipratropium bromide, IV magnesium (can bronchodilate)
if life threatening: add, systemic corticosteroid
in an asthma attack, will both sides of the chest expand?
yes
will breath sounds be the same on both side?
yes
will the lung be resonant on both sides?
yes
will there be wheezes from narrow airways?
yes
what are some features of high risk patients?
previous near fatal asthma previous admission within past year 3 or more anti asthma drugs repeated A&E attendance brittle disease poor compliance mental health issues alcohol or drug abuse obesity social problems, stress
how should the severity of an exacerbation be assessed?
peak flow before and after response to nebulised salbutamol
blood gases
what indications are there for ventilatory support?
worsening hypoxia or hypercapnia resp or cardiac arrest resp acidosis impaired consciousness peak flow less than 20% and not improving with nebulised saba
