Asthma Flashcards
what is asthma
diffuse airway inflammation due to a variety of stimuli resulting in reversible partial or complete bronchoconstriction
summarise the pathophysiology of airway inflammation
bronchoconstriction
airway inflammation and oedema
hyper-reactivity due to narrowing of airways
airway remodelling (desquamation, angiogenesis etc)
what causes asthma?
exercise allergies pollen dust smoke
what are the symptoms of asthma
dyspnea, chest tightness, audible wheeze and cough
what are the signs of asthma
wheeze, tachypnea, tachycardia, pulsus paradoxus, hyper-inflation of chest, hyper-resonant percussion note, visible effort to breath, expiration phase prolonged
what are the signs of a severe asthma attack
resp rate >25
pulse >110
inability to complete sentences
PEF 30-50% of normal
what are the signs of a life threatening asthma attack
cyanosis exhaustion altered conscious level silent chest arrythmias type 1 resp failure O2 <92 PEF <33%
what questions do you ask in annual reviews for asthma
have you had trouble sleeping due to your symptoms
do you have your usual asthma symptoms in the day
has it interfered with your daily activities
what are normal breath sounds called
vesicular, longer inspiration than exp
what are bronchial breath sounds and when are they heard
abnormality in lung that is far from airways
heard in consolidation, lobar collapse with patent bronchus and lung cavity
gap between both phases, equal
how can you check for further consolidation
tactile fremitus
say 99 = shouldn’t be loud
say e
whispering
what types of wheeze are commonly heard
expiratory
polyphonic - heard if bronchioles are spasming
monophonic - small wheezing starting at different times - heard if pathology in local area
when are crackles or crepitations heard
on inspiration, in pneumonia, COPD, pulmonary fibrosis or oedema, lung abscesses
what are the two types of crackles
coarse v fine
what is a pleural friction rub and when is it heard
sounds like walking on snow, when two pleura rub against each other due to pleurisy
also in consolidation, pulmonary infarction
stridor
loud, high pitched crowing sound during inspiration
caused by UPPER airway narrowing - don’t need a stethescope
what is FVC
amount of air person can exhale after maximally inhaling
what is FEV1
vol of air you can exhale in one second after maximally inhaling
what is a normal FVC/FEV1 ratio
70%
what is the ratio in obstructive lung disease
<70%
COPD
what is the ratio in restrictive lung disease and give an example
> 70%, but FVC alone is decreased
pulmonary fibrosis
why do you get inspiratory crackles, and with which conditions would you hear coarse v fine crackles?
bc if peripheral airways have collapsed, then on inspiration the airways open and the alveoli are delayed on opening and hence you hear crackles
coarse - COPD
fine - pulmonary fibrosis
what is diffusing capacity for CO
partial pressure difference between inspired and expired O2, and hence extent of absorption into blood
asthma = normal or increased COPD = decreased due to decreased effective alveoli surface area
what are the normal values for ABGs
o2: 10-13 (if they are on oxygen, <11 is cause for concern)
co2: 4.5-6
pH: 7.35-7.45
HCO3: 22-26
base excess: -2 to +2
FIND TABLE FOR ACIDOSIS AND ALKALOSIS
