exercise induced bronchoconstriction Flashcards
when are symtpoms of exercise induced bronchoconstriction worse
typically worst 5-10 minutes after stopping exercise, not during exercise
DDx for new onset exercise related symptoms
poor cardiopulmonary fittness
upper airway dysfunction (relatively common in young women)
hyperventilation
psychological conditions eg. anxiety
obesity
cardiac abnormalities
other lung conditions (COPD, Infection)
what is the main investigation
spirometry before and after bronchodilator
if there is reversibility of airflow limitation following bronchodilatr
make dagnosis of asthma and treat
if the symptoms are consistant with exercise induced bronchoconstriction but spirometry before and 10-15 minutes after bronchodilatr shows no or little response
consider referral to respratory physcian or to an accredited respiratory function laboritory for indirect challenge testing
symptoms of exercise induced bronchoconstriction
cough, wheeze, tightness in the chest, breathlessness, excessive mucus production
some children experience chest pain with exercise induced bronchoconstriction
younger children recover faster than older children and adults
when do symptoms peak
10-15 minutes faster after execrise
refractory period
after an episode of exercise induced bronchoconstriction, 50% of people experience a refractory period of 2-3 hours, dduring which they do not develop bronchoconstriction even if they exercise
aetiology of exercise induced bronchoconstriction
ventilatory rate is high during exercise meaning airways must heat and humidify a large volume of air in a short time
dehydration of the airway leads to release of inflammatory mediators within the airway and contraction of the airway smooth muscle
upper airway dysfunction
intermittant, abnormal adduction of the vocal cords during respiration resulting in variable upper airway obstruction
often mimics asthma
