Lecture 6: Asthma Flashcards
Define asthma.
Reversible, obstructive lung disease caused by increased airway sensitivity.
What pathophysiologic characteristics are seen in asthma?
- Inflammatory cell infiltration with eosinophils, neutrophils, and T-lymphocytes.
- Goblet cell hyperplasia
- Thick mucus plugging small airways
- Hypertrophy of smooth muscle
- Airway edema
- Mast cell activation
What are the two physical factors that ultimately lead to asthma?
- Airway obstruction
- Bronchiole constriction
What is the strongest, identifiable, predisposing factor for development of asthma?
Atopy
What are the risk factors for asthma?
- Obesity
- Respiratory irritants
- Pollutants
- Weather (cold)
- Environment
- GERD
- Viruses
- URIs
- Exercise
- Stress
- BBs
- NSAIDs/ASA
- FMHx
When does most asthma begin by?
< 5 years of age
77%
What asthma type is uncommon and typically idiopathic?
Intrinsic asthma.
What confirms a diagnosis of asthma?
Spirometry w/ reversibility test.
Usually not done until age 5
Can also do allergy testing.
Perform normal spirometry
Give BD and then perform spirometry again.
What are the primary S/S of asthma?
- Cough
- Chest tightness
- SOB/Dyspnea
- Difficulty breathing
- Episodic wheezing
What do nasal polyps in the nose for a suspected asthmatic child suggest?
CF
In an adult, might just be benign.
What PE findings might suggest asthma?
- Nasal secretions/mucosal swelling and/or nasal polyps
- Atopy, ocular shiners, salute sign
- Wheezing, prolonged expiratory, hyperexpansion of thorax
On a lung exam, what should be documented regarding the 4 parts of a lung exam?
- Inspection: shape and movement
- Palpation: reduced if hyperinflated, maybe reduced tactile fremitus
- Percussion: normal to hyperresonant
- Auscultation: Rhonchi to wheeze, prolonged expiratory, or even silent chest in severe.
For a child >= 5 years old, what is the spirometry criteria to diagnose asthma?
- Reduced FEV1/FVC (< 85% for a child)
- Increased FEV1 post BD
What substances does bronchoprovocation testing use to induce an asthma attack?
- Histamine
- Methacholine challenge test
- Mannitol
Not indicated if FEV1 < 65%
What at home testing is good to monitor asthmatics with?
Peak flow meters
When are CXRs indicated for asthma?
- Initial diagnosis of asthma
- Uncertain diagnosis from PFT
- Refractory acute asthma attack/status asthmaticus to r/o other causes and complications.
MC finding is nothing!
What might we see elevated in a CBC for asthma?
- Eosinophils
- IgE as well.
What might be seen in a sputum culture/sample of an asthma patient?
- Charcot-Leyden crystals (Crystals of eosinophils)
- Curschmann spiral (Shed epithelium)
Both are specific to asthma.
What is the methacholine challenge and what is a significant finding?
- Inhalation of increasing methacholine dosages and PFTs.
- Increased airway hyperresponsiveness with a >= 20% decrease in FEV1 per max dose.
Only inpatient and expensive.
What is the golden rule about asthma?
All wheezes are not asthma!
Could be a far more severe condition
What is tussive syncope?
Fainting from coughing
What is the criteria for mild intermittent asthma?
- daytime symtoms <=2 days/week
- <=2 night awakenings/month
- use of SABA <=2 days/weeks
- No functional impairment between exacerbations.
- FEV1 >= 80% between exacerbations.
- FEV1/FVC normal between exacerbations.
- 0-1 exacerbations requiring oral glucocorticoids per year.
Essentially, asthma attacks happens 2 or less times a week and it doesn’t affect you otherwise.
What is the criteria for mild persistent asthma?
- daytime symptoms more than twice a week (not daily)
- 3-4 night awakenings per month
- use of SABA > twice a week
- Minor interference with normal activities
- FEV1 normal and FEV1/FVC normal
- 2+ exacerbations requiring oral glucorticoids annually.
Essentially, more frequent than mild intermittent, but not heavily impactful on your day-to-day
What is the criteria for moderate persistent asthma?
- Daily symptoms
- Nighttime awakenings > once a week
- Daily SABA use
- Minor limitations in normal activities
- FEV1 60-80% and FEV1/FVC lowered.
Not able to go on a run.
What is the criteria for severe persistent asthma?
- Daily symptoms
- Nighttime awakenings nightly
- Multidaily SABA use
- Extremely limited
- FEV1 <=60%, FEV1/FVC below normal.
When is levalbuterol used over albuterol?
Presence of cardiac issues (It should have less cardiac SEs)
However, it is more expensive.
Main SEs of SABAs:
Tachycardia
Nervousness
Shakiness
I emailed Davis about it and she said its just a clinical pearl, won’t be tested on. Articles say it has no diff in SE.
What are the inhaled corticosteroids used for asthma?
- Budesonide/pulmicort (Neb/Inhaler, so it can be used in children/babies)
- Beclometasone/Qvar (inhaler only)
- Mometasone furoate/Asmanex (inhaler only)
- Fluticasone propionate/Flovent (inhaler only)
Preferred long-term controller
What are the most common SEs with inhaled corticosteroids?
- Thrush
- Hoarseness
- Localized hypersensitivity
- Cough and throat irritation
Rinse mouth out after use.
Also caution about systemic symptoms.
What medical history is pertinent in prescribing an ICS?
- H/o of glaucoma
- Growth levels (BMI < 15)
- Calcium and Vit D intake
What ICS inhalers are recommended in pregnant women?
- Budesonide
Can also use albuterol/proventil, but ICS is preferred.
What are the systemic corticosteroids used for acute asthma attacks?
- Prednisone (pill)
- Prednisolone (liquid)
- Solumedrol (IM/IV)
PO preferred if no IV access.
Oral and IV have the same onset for these meds.
What are the SEs of systemic corticosteroids?
- SSTI
- Cushing/weight gain
- Cataracts/glaucoma
- CV disease
- GI disease
- Hyperinsulinemia w/ insulin resistance
When are LABAs used?
Already on a SABA and ICS. Adjunct therapy
Salmeterol
Formoterol
Arformoterol
But usually combined with an ICS in a combo.
What additional SEs can LABAs cause over SABAs?
- Cramping of hands/legs/feet
- Overuse can worsen symptoms
For an acute asthma attack nonresponsive to a SABA, what is the usual next step?
Anticholinergics, such as:
- Ipratropium bromide (atrovent)
- Tiotropium bromide
- Ipratropium and albuterol
Relax airway, prevent narrowing, and reducing mucus.
What is theophylline?
- A non-selective phosphodiesterase enzyme inhibitor.
- Enhances mucociliary clearance and anti-inflammatory.
Mainly only in mod-severe asthma. Need to monitor serum concentrations.
What are the leukotrienes and their MOA?
- Montelukast/singulair
- Zafirlukast/accolate
MOA: Leukotriene receptor antagonist
Overall, improves symptoms, reduces exacerbations, and limits markers of inflammations such as eosinophil counts.
When is cromolyn used and what is it?
- Used when intolerant of ICS for asthma.
- Mast cell stabilizer
- Reduces airway reactivity.
Neb only.
What is racemic (nebulized) epi mainly used for?
- Severe Croup
- Last resort for severe asthma
Slightly more beta-2 agonist.
Racemic = quick peak, quick onset, 1-3 hours and then it is gone.
Need to monitor after administration for 4 hours!!!!!!
What MAB is used for asthma?
Omalizumab/Xolair.
Injectable that targets IgE mast cells.
Must be an allergy-related asthma.
Also used in chronic, idiopathic urticaria.
Can cause anaphylaxis as BBW.
In general, what would you first prescribe to a newly diagnosed patient with asthma over 12 yo?
- SABA PRN
- Low dose ICS daily or PRN w/ SABA.
What are the 6 steps of asthma treatment?
- SABA + low dose ICS when symptomatic or low dose daily.
- SABA + low dose ICS
- SABA + low dose ICS + LABA OR medium dose ICS only.
- SABA + medium dose ICS + LABA
- SABA + high dose ICS + LABA/montelukast
- SABA + high dose ICS + LABA/montelukast + oral steroids + (consider MAB)
AKA start with a SABA and low dose ICS and slowly go up.
How often is asthma followed up on?
- Routine: 1-6 months
- Adjusting meds: 2-6 weeks
Once stable for 3+ months, consider stepping down treatment.
What ethnicities have lower predicted values on peak flow meters?
- Black
- Hispanic
10% lower predicted
How do we determine asthma control?
How often they have symptoms weekly.
At what asthma step do you refer out to pulm or an allergist?
- > 5 yo = step 4 or higher (SABA + med dose ICS + LABA)
- < 5 yo = step 3 or higher (SABA + low dose ICS + LABA or med dose ICS
What is Exercise Induced Asthma? (EIA)
- Airway narrowing during vigorous exercise
- usually at onset of exercise or within a few mins.
How do we treat EIA?
Trial SABA
What is cough variant asthma and how we do treat it?
- Chronic non-productive and nocturnal cough > 3 weeks.
- Treated same as asthma
Generally a r/o cause.
Usually normal PFTs.
What are the warning S/S for an acute asthma attack in an adult?
- Increased SOB or wheezing
- Disturbed sleep
- Angina/tightness
- Increased SABA use
- Fall in peak flow rate
What are the warning S/S for an acute asthma attack in a child?
- Audible wheezing/whistling
- Coughing frequently or in spasms
- Waking at night
- SOB
- Chest tightness
What is status asthmaticus?
- Most severe form of asthma.
- Lungs are inadequate to provide adequate perfusion
- Leads to organ dysfunction and ARDS
- Requires intubation and ventilator support.
How is an acute asthma attack treated in office?
- Nebulized albuterol + O2 check
- 2nd neb (duoneb) + O2 check
- 3rd neb + O2 check
If not > 94% or in severe distress still, refer to ER.
3 neb treatments is only for mild-mod.
