asthma Flashcards
epidemiology in US
MC:
- boys (< 14 years old)
- women in adulthood
- black > white
burden: high economic and personal burden exists for people with asthma
- miss work and school
asthma pathophysiology
- Chronic inflammation of the airways
- Results in hypertrophy and mucus plugging of the bronchioles
-Involves widespread, variable airflow limitation
-reversible: spontaneously or with treatment) - Airway inflammation → disease chronicity → hyper-responsive airway + limited airflow + respiratory symptoms
risk factors for development of asthma
Genetics: Atopy
-Predisposition to develop IgE in response to environmental allergens
-High IgE: more likely to have allergic response
-Parent has asthma
Environmental exposures
Contributing factors
–
non-atopic triggers + onset
Nonallergic: usually develops in age > 35
Non-atopic: infections, viral, air, medicine
-Ozone
-Smoke
-Particulate matter
-Infection
-Some medications
(aspirin, beta blockers, ACE inhibitors)
-Cold, dry air
atopic triggers + onset
Allergic triggers: usually begins in childhood
-House dust mite
-Pollen
-Ragweed
-Cockroach
-Mold
-Pet dander/saliva
-Foods (peanuts, soy, shellfish, milk)
-Natural oils and fragrances
In diagnosing asthma what is important to ask in Medical History?
Symptoms -patterns, frequency, severity
PMH, FAM HX
asthma: physical exam signs + severe asthma signs
Signs:
- Wheezing
- Hyper-expanded thorax (chronic air trapping)
- Nasal secretions, nasal polyps - Derm exam: atopic
dermatitis, eczema → triad!
Severe asthma:
- airflow may be too limited to produce wheezing
-Auscultation:
- GLOBALLY reduced breath sounds with
- PROLONGED expiration
- ABG changes
Asthma: spirometry
Testing of lung function
-Determines presence and extent of airflow obstruction & if reversible
Airflow obstruction
- Reduced FEV1/FVC ratio (< 90% pred)
Reversibility
- Increase of ≥ 12% and 200 ml in FEV1
chest xray- asthma
Chest radiographs: normal
-Hyperinflation common (if active disease)
-may have bronchial wall thickening (edema and muscle wall hypertrophy)
Useful in ruling out other conditions:
-Pneumonia, CHF or complications of asthma (pneumothorax)
asthma control test chart
-its really important you are asking the right questions….asthma is very under appreciated
-many people report being fine and doctors too -> but in reality they are not well controlled
People walking around with asthma overestimate their hindrance on life
classification of asthma control:
based on sx, nighttime awakening, SABA use, interference with daily life, FEV1, number of exacerbations
Well controlled: symptoms < 2 days/week, night time awakening < 2 days/month, no interference w/ normal activity, FEV1 > 80% predicted/personal best, 0-1 exacerbations per year, SABA use < 2 days/week
Not well controlled: symptoms > 2 days/week, night time awakening 1-3x/week, some interference w/ normal activity, FEV1 60-80% predicted, >2 exacerbations per year, SABA use > 2 days/week
Very poorly controlled: symptoms throughout the day, night time awakening >4x/week, normal activity extremely limited, SABA use several times a day, FEV1 <60%, >2 exacerbations per year
stepwise approach for managing asthma
- Step 1: SABA
- Step 2: SABA + low ICS
- Step 3: SABA + low ICS + LABA
- Step 4: SABA + med ICS + LABA
- Step 5: SABA + high ICS + LABA
- ## Step 6: SABA + high ICS + LABA + oral GC
-step 5 + 6: consider omalizumab for pts who have allergies
-when nothings working -> think about biologics
–
Step up - what to check first and step down - when should you do it
Step up if needed and check:
- adherance
- environmental control
- comorbid conditions
Step down if possible (well controlled for at least 3 months)
medications to tx asthma: how to use a spray inhaler
-health care provider should evaluate inhaler technique at each visit
-stand up, breathe out
-as you start to breathe in -> push down on top of inhaler -> keep breathing in slowly
-hold your breathe for 10s
-breath out
-pMDI- hardest to use
-first thing you do when pt is being txed and are uncontrolled -> ask them to use inhaler in front of you -> if they are doing it perfectly….then consider stepping up
–
dry powder inhaler
-need to generate more negative expiratory force for this
-not an issue for asthma but issue with COPD
–
nebulizers
-Uses compressed air machine to deliver medicine as a mist
Indication:
-small children
- elderly
- Altered mental status
- limited negative expiratory force
- severe asthma episodes
-SABA, LABA, ICS available in nebulized form
–
Medications: acute relief
used in acute asthma episodes:
- SABA: (Albuterol)
- combo SABA : (albuterol w/ ipratropium nebulizer)
–
long term control
Taken daily to:
-reduce inflammation
- relax airway muscles,
- improve sx and pulmonary function
-
Meds:
-LAMA
-LABA
-Leukotriene modifiers
-Immune modulators and mast cell stabilizers
- ICS: fluticasone, budesonide
Tiotropium
Blocks bronchoconstriction
-long acting anti-cholinergic
-LAMA- long acting muscarinic antagonist
-long-term maintenance treatment in asthma
-An alternative to a long-acting beta agonist for patients over age 6
leukotriene receptor antagonists (LTRAs)
montelukast - PERSISTENT ASTHMA
pharm notes:
receptor blockers decrease leukotriene activity to reduce inflammation; use in conjunction with beta agonists for long term therapy
montelukast has less ADR and DI
use in kids over 12
immunomodulators (step 5)
IgE Mediated Asthma
- Omalizumab (Xolair)
Eosinophilic Mediated Asthma (IL-5):
-Benralizumab (Fasenra)
-Mepolizumab (Nucala)
-Reslizumab (Cinqair)
Mixed Eosinophilic and Allergic:
-Dupilumab (IL-4,13)
-Tezepelumab (TSLP)
-Methylxanthines- THEOPHYLLINE
-biologics
–
asthma management goals
-Control symptoms
-Prevent exacerbation
-Maintain lung function as close to normal as possible
-Avoid adverse effects from medications
-Prevent airway remodeling (irreversible airway obstruction) **
-Prevent asthma mortality
Severe airflow obstruction: PEF values less than _____ L/min =
200 L/min
Indication of severe attack:
- FEV1 or PEF: _____
- FEV1 or PEF: <40%
A 20% change in PEF values from morning to afternoon or from day to day = ______ controlled asthma
Inadequately controlled asthma:
When should pts with mod-severe asthma check PEF?
-Every morning and evening
-After an exacerbation
-Before inhaling certain medications to monitor response
check kids bc they cant verbalize
indications of a severe attack
-Breathless at rest
-Hunched forward
-Talking in words rather than sentences
-Agitated
-FEV1 or PEF< 40%
–
what is PEF?
Peak expiratory flow: L/min
it is the max SPEED a person can exhale something
you use an at home self-monitoring test (i think jennifer has this)
BELOW 200 L/min: severe airflow obstruction
<40% of normal PEF indicates a severe attack!!
A 20% change in PEF values from morning to afternoon or from day to day = uncontrolled asthma
350-550ish are normal
severe exacerbation tx (inpatient)
Pts should immediately receive:
-Oxygen
-High doses of an inhaled SABA + ipratropium q 20 min intervals or continuous for an hour
-SYSTEMIC corticosteroids
–
vaccines
-Pneumococcal vaccine (Pneumovax)
-Annual influenza vaccinations
–
DLCO asthma vs COPD
-asthma normal
COPD:
- Emphysema: low
- Chronic bronchitis: normal
