Clin Med - Asthma Flashcards
Define asthma
Chronic inflammatory disorder of the airways resulting in episodes of reversible inflammation causing airflow obstruction
Asthma pathology
Hypertrophy of the bronchial smooth mm, mucosal edema, mucous production, airway muscle tightening
Risk Factors for Developing Asthma
- Family history: 40x more likely if parent has asthma
- Family size
- Socioeconomic factors
- Race/Ethnicity
- Gender: boys early, girls later
- Prematurity/Birth weight
- Atopy
- Eczema
- Obesity
- Lower Respiratory Infection (RSV, PIV, Adenovirus, Chlamydia, Mycoplasma)
- Diet: deficient in fruits and vegetables
- Maternal smoking
Environmental risk factors
Allergans vs. irritants.
Allergans: dust mite, animal dander, cockroach, indoor/outdoor mold, pollen.
Irritants: tobacco smoke, other smoke, fumes, air pollution
Potential Triggers for Acute Symptoms
- Viral Illnesses
- Cold Air
- Weather Changes
- Emotions
- Foods
- Medications
- Exercise
Signs & symptoms
-range from mild to severe, sometimes even fatal
-between attacks patient may have few, if any symptoms
-episodic wheezing, chest tightness, SHOB/DOE, cough
Severe attacks: use of accessory MM, nasal flaring, unable to talk in sentences, diminished breath sounds, audible wheezing, respiratory distress/anxiety/panic
Amount of wheezing is not a reliable indicator for severity of episode!!
Physical exam
tachypnea, tachycardia, hypoxemia, percussion often normal or hyperresonant, palpation normal, tripoding
What is the most important part of diagnosing asthma?
History & physical
What are the 4 causes of chronic cough?
- Lung disease
- Reflux
- Upper airway cough syndrome
- Drug side effects
Diagnosis of asthma
Some patients will report all three of the classic symptoms of asthma, while others may report only one or two:
- -Wheeze (high-pitched whistling sound, usually upon exhalation)
- -Cough (often worse at night)
- -Shortness of breath or difficulty breathing
Asthma and Spirometry
A symptom pattern suggestive of asthma AND airflow limitation on initial spirometry, which completely reverses to normal following bronchodilator, virtually clinch the diagnosis of asthma.
What are peak flow meters used for?
To set an action plan based on your personal best.
When should you prescribe biologics?
When you max out therapy or you find a patient that’s a severe allergic asthmatic (via blood work)
Severity components of intermittent asthma
- Symptoms < once a week
- Nocturnal symptoms < 2x a day/month
- Interference with activity - brief exacerbations
- SABA use < = 2 days per week
- PFT: normal FEV1 between exacerbations, FEV1 > 80% predicted, FEV1/FVC normal
Recommended treatment strategy for intermittent asthma
Step-1:
Preferred - SABA PRN
Severity components of mild asthma
- Symptoms > than 2x per week, but not daily
- Nocturnal symptoms 3-4x/month
- Interference with activity - exacerbations may cause minor limitation of sleep and activity
- SABA use > 2 days per week, but not daily and not more than once on any day
- PFT: FEV1 > 80% predicted, FEV1/FVC normal
Recommended treatment strategy for mild asthma
Step-2:
Preferred: low-dose ICS
Alt: Cromolyn, LTRA, Nedocromil, or Theophyline
Severity components of moderate asthma
- Symptoms daily
- Nocturnal symptoms more than once a week, but not every night
- Interference with activity - exacerbations more than 2x/week, may cause some limitation of activity and sleep
- SABA use daily
- PFT: FEV1 > 60%, but < 80% predicted, FEV1/FVC reduced 5%
Recommended treatment strategy for moderate asthma
Step-3:
Preferred: low-dose ICS + LABA or medium-dose ICS
Alt: low-dose ICS + either LTRA, Theophiline, or Zileuton
Consider PO steroids
Severity components of severe asthma
- Symptoms throughout the day
- Nocturnal symptoms often every night per week
- Interference with activity - frequent exacerbations with marked limitation of physical activity
- SABA use several times per day
- PFT: FEV1 < 60% predicted, FEV1/FVC reduced 5%
Recommended treatment strategy for severe asthma
Step-4:
Preferred: Medium-dose ICS + LABA
Alt: Medium-dose ICS + either LTRA, Theophyline, or Zileuton
Step-5:
Preferred: high-dose ICS + LABA and consider Omalizumab for patients who have allergies
Consider PO steroids
Beta2 agonists MOA
directly stimulate beta-adrenergic (beta2) receptors causing bronchial relaxation
*short/long acting beta agonist (SABA/LABA)
Give examples of SABA and LABA
SABA: Albuterol and Levalbuterol
LABA: Salmeterol
Anticholinergics MOA
produces bronchodilation by relaxing airway smooth muscle by blocking acetylcholine-induced bronchoconstriction
*short/long acting muscarinic antagonist (SAMA/LAMA)
Give examples of anticholinergics
SAMA: Ipratropium (Atrovent), Ipratropium + albuterol (Combivent or Duoneb)
LAMA: Tiotropium (Spiriva), Aclidinium (Tudorza), Umeclidinium (Incruse)
LAMA/LABA: Umeclidinium/Vilanterol (Anoro Ellipta), Tiotropium/Olodaterol (Stiolto)
Inhaled corticosteroid (ICS) MOA
nonspecific anti-inflammatory
Examples of ICS
ICS: Ciclesonide (Alvesco), Beclomethasone (Qvar), Mometasone (Asmanex), Fluticasone (Flovent), Budesonide (Pulmicort)
Combination ICS/LABA
Fluticisone/salmeterol (Advair), Budesonide/Formoterol (Symbicort), fluticasone/vilanterol (Breo Ellipta), Mometasone/formoterol (Dulera)
What biologics are prescribed for asthma?
- Omalizumab (Xolair) - IgG monoclonal ab
- Mepolizumab (Nucala)
- Benralizumab (Fasenra)
What is IL-5?
IL-5 is the major cytokine responsible for the growth and differentiation, recruitment, activation, and survival of eosinophils (a cell type associated with inflammation and an important component of the pathogenesis of asthma).
Which biologics inhibit IL-5?
Mepolizumab (Nucala) & Benralizumab (Fasenra)
Quick relief plan is same for all classifications…
- Short acting inhaled B2 agonist as needed
- Intensity of treatment will depend on severity of exacerbation
- Use of short-acting B2 agonist >2 times a week may need to move to long-term control therapy
- If on long-term control therapy and using short-acting B2 agonist on daily basis, or increasing frequency of use indicates need to move to next step (“step up”)
What role does IgE play in asthma?
IgE binds to allergens and triggers the release of substances from mast cells that can cause inflammation.
What immunocaps should you draw?
- Midwest Panel: trees, grass, weeds
- Perinneal Panel: molds, cat/dog dander, dust mites, cockroaches
- Could they be a Xolair candidate? IgE > 35 with multiple allergens
What is considered good asthma control?
- Daytime symptoms < 4 times/week
- Night-time symptoms < 1time/week
- Normal physical activity
- Mild, infrequent exacerbations
- No asthma-related absence from work/school
- B-agonist use < 4 times/week
- Peak expiratory flow without much diurnal variation
Characteristics of mild exacerbation
- Minor changes in airway function
- Minimal signs and symptoms
- Most patients respond quickly and fully to inhaled short-acting B2 agonists (may need to administer every 3-4 hours for 24-48 hours)
- If not taking inhaled corticosteroid, initiation may be indicated
- If taking inhaled corticosteroid, double dose until peak flow returns to normal
- 3-10 days of systemic steroid may be indicated if no response to initiation of, or increased dose of, inhaled steroid
Moderate-to-Severe Exacerbations -
Need for hospitalization is based on…
- Response to initial treatment
- Duration and severity of symptoms
- Severity of airflow obstruction
- Course and severity of prior exacerbations
- Access to medical care
- Adequacy of social support and home conditions
Mod-to-Severe exacerbation discharge criteria
- PEF or FEV1 is >70% of predicted or personal best
- Minimal to absent symptoms
- Monitor patient for 30 minutes after last bronchodilator treatment to ensure stability of patient
Pediatric Asthma Meds
Albuterol inhaled: (short acting)
<2yo- 0.05-0.15 mg/kg NEB q4-6h
2-5yo – 0.1-0.15 mg/kg NEB q4-6h
>5yo – 2.5mg NEB q4-6h
Salmeterol inhaled: (long acting)
>4yo – 50mcg/blister 1 puff inhaled q12h
Cromolyn sodium:(mast cell stabilizer)
>2yo – 20mg/2ml NEB one vial qid then bid
Budesonide: (inhaled corticosteroid)
1-8yo – 0.25-0.5 mg/day NEB div qd-bid
Pediatric Asthma Exacerbation Treatment
- Increase frequency of NEB albuterol to q2-4 hrs
- 5 day course of oral steroid (Prednisolone 15mg/5ml 1mg/kg q24 hours)
- Continue/begin oral antihistamine
- If s/s last > 7 days and/or pt develops fever, fatigue, sputum production, etc = consider antibiotic treatment.
When to worry…
Nasal flaring
Retractions of stomach/chest muscles
Lack of wheeze (Silent Chest)
Fatigue (Floppy Baby)
Before this exam make sure you….
Review the asthma tables from lecture :)
