Asthma

author 1, author 2 January 01, 2025 #hypersensitivity #airway and ent

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Started: Symptoms: wheezing/cough/chest tightness/SOBOE Triggers: exercise, cold air, irritants (perfumes), aeroallergens, pets, infections, medications, laughing Mainly night vs day Puffers: Daytime /week Waking up at night? / week Rescue / week missing work/school Response to SABAs, ICS, Montelukast, Prednisone was nil/weak/fair/substantial. Never required prednisone, ER visits, hospitalization, ICU admission, or intubation/mechanical ventilation ?GERD?

Asthma

  • Symptoms of *** with PFTs showing *** are consistent with a diagnosis of asthma (increase in FEV1 and/or FVC ≥12 % over baseline and ≥200 mL with bronchodilation)
  • phenotype is felt to be allergic/eosinophilic/nonallergic/ intermittent (exercise induced vs. occupational vs. viral induced)
  • Symptoms are currently uncontrolled/partly controlled/controlled on meds with compliance/technique (>2 daytime, woken up at night, activity limitation, rescue >2)
  • Relevant comorbidities include rhinosinusitis, OSA, GERD, obesity, and depression.
  • Baseline spirometry, SPT, FeNO
  • Methacholine / Exercise challenge test given diagnostic uncertainty
  • Ad-hoc: OSA study

Comorbid conditions that can exacerbate symptoms should be optimized. These include smoking, obesity, obstructive sleep apnea, nasal polyps, allergic rhinitis, anxiety, de-conditioning, viruses, and pollution exposure Pharmacologically:

  • Symbicort 200/6 1 puff PRN (up to 8 puffs/daily) for mild intermittent asthma or issues with adherence (as per the SYGMA2 trial)
  • Symbicort 200/6 1-2 puffs BID
  • Triple therapy with: Breo Ellipta 100/25 or 200/25 mcg 1 puff daily
  • If in exacerbation: prednisone 50mg PO OD x 5 days with a taper, vs present to the ED

We reviewed the importance of adherence to medications with proper technique As they are well controlled, we discussed stepping down therapy to:

Patients with adherence issues -

t

asthma epid

common: 12+ (adult), 8% Canadians LOTS of visits a year to hospital ~500 deaths a year $$$ burden a lot of that money is also from SEVERE asthma

however, a lot of this is probably from undertreatment of asthma and poor assessment of asthma control there is often a DISCORDANCE between patient reported level of control and what is ACTUALLY controlled...

severe asthma

symptoms of poor control despite maximum doses of conventional treatments

pathophysiology

small airways chronic inflammation and hyper-responsiveness => reversible airflow obstruction biggest drivers cellular are eosiniophils and mast cells

phenotypes

LOTS of phenotypes age onset varies allergic vs non allergic different inflammatory symptoms (TH2 vs non) via the cellular driver ... etc

the problem is, asthma is also a heterogenous disease

approach

guidelines: GINA and CTS (GINA is great)

diagnosis

history, physiucal exam, investigations

history

Cardinal: cough, wheeze, chest tightness, shortness of breath

increased probability of asthma :

  • more than one type of sypmotm: (ie if JUST cough less likely asthma)
    • wheeze, shortness of breath, copugh, chest tighteness
    • wheeze is the MOST speocifc
  • worse at night or early AM (has to do with diurnal cycle)
  • varys over time and in intesity
  • associated with triggers: allergens, laujghter, cold air, exericse

DECERASED prob

  • isolated cough
  • sputum production
  • associatged with dizziness, light headedness of peripheral tingling (ie cardiac stuff)
  • chest pain
  • exercise SOB with noisy INSPIRATION

NB: ddx for wheeze

  • URTI
  • COPD
  • upper airway dysfunction (ie ILO)
  • endobronchial obstruction
  • ionhaled forigen body

phsyiucal exam

often normal unless in flare

spiormetry

new: FEV/FCV1 <5th percentile now -.165 revisity FERV or FVC > 10% of predicted value

ie (FEV1 pre - post)/normal ref value
this is NEW compared to the 200ml and 12% reliatve to inital value

HOWEVER: changes in FEv1 and FVS are inversly proptional to lung volume

bronchodilator given in 4 puffs venotlin, wait 15 mins

Look at GINA diagnostic pathway

if spiromery is not supportive but everything else is and there's no other ddx altenragive then options incdlue:

  • treat mepircally, repeat the test, bronchoPROVOCATION testing (ie MCT)?

bronchprovcation tests

speciifc airway irritants (ie alelrgens, oocupations stuff) nonsepcific pharm agents methacolihe for example or indierect stimul8 (exericse, cold air, maniitol)

  • exercise, eucapnic volumatyr hypertension, cold air hypertgenion, hyupertnonc saline, manniotl, AMP
  • why does it happen: lots of inflmamatory cells (mast cells ie) can be induced by changes in osmolairty: exercise and cold air alter the humidity of the air you're breathing.
  • for excercise, treatmill or bicycle
    • duration 6-8 minuites with 4-6 minutes near max levels
    • hR 90% pred goal

for MCT most widely used method direct stim of bronchial smooth muslce VERY sensitive tests hard to get sometimes

some variance in how to interpret or the numbers used for it see table

flare history

typically it's NOT super acute it takes some days - 1-2 weeks before the worst

risk factors

prior intuvation flare in last 12 months low FEV1 incorrection techbniquhe poor asdehrcen smoking obesity pregnancy blood eosinophilia

control?

I like GINA

in the past 4 weeks:

  • daytime asthma symptoms more than twice weekly
  • any night wakings due to ashtma
  • reliver needed for symotms more than twice weekly
  • anyt activity limitationd ue toasthma

treatment

goals: sx and risk reduction of flares

controller:

reliver:

lungs on fire: want something to put out the fire another to opena window so you can breath if needed

asthma control vs severity

severeity: level of treatment required to achieve control cna only be assessed after several montsh of therapy but what level of treatment is needed to constitue that it somehwat unclear

GINA also says that you should n't be doing high dose ICS anymore once you're at that poiint you should be thinking about other stuff...

insert table about doses of ICS CTS table is nice GINA is also nice insert

starting tyreatmet options

tailor based on presnetaiton severity if mild just do PRN if flare to the ED just start them on medium dose ICS-fomo with reliver too

GINA has a great table regarding this

other tidbits

idetnfity triggers treat comorbid conditions (ie rhinits, GERd, etc) disease modifying treamtents potneitally (ie allergy immunotherapy) SLIT esp if FEV1 >70% see the cochrane review of this for SLIT it's great: )