laboratory tests for asthma diagnosis?
- spirometry: fev1/fvc less than 80%
- 12% fev1 increase with brochodialtor
- cbc count esnophil increase indicate allergic component. and iges
- ABGs: severe distress, suspected hypoventilation, or PEFR or FEV1 30% or less after initial treatment.
5: pft performed for 5 yrs or older
6: oximetry to check hypoxemia
Spirometry may be normal if the patient is not symptomatic.
Complications of asthma
* Status asthmaticus*
Severe, life-threatening attack refractory to usual treatment where patient poses risk for respiratory failure
asthma categories
Acute Asthma
Chronic Asthma
* Intermittent Asthma
* Persistent Asthma
Mild
Moderate
Severe
Desired Outcomes in Chronic Asthma
- Maintaining Long-term Control
- using the Least Amount Of Medications
- Minimizing ADR.
Desired Outcomes in Acute Asthma
treatment goals
- Correct significant hypoxemia
- Reverse airflow obstruction rapidly
- Reduce the likelihood of exacerbation relapse or recurrence of severe airflow obstruction in the future
non pharmacological treatments of asthma
- patient education
- avoid triggers
- vacinnation
- avoid medications
Patient education in asthma
- Asthma trigger avoidance
- Proper administration of inhaled medications
- Asthma self-management
vaccination needed for asthmatic patient
- influenza yearly needed for patient of 6mnths or older
- Pneumococcal Polysaccharide Vaccine needed dose before age 65 and one after 65
drugs that cause asthma
- non selective Beta Blockers
- Aspirin & NSAIDs
For patients with asthma requiring β-blocker therapy, a β1-selective agent is the best option.
asprin sensitivity adults present with rhinitis and nasal polyp with asthma
What is the best route of administration of asthma medications & why?
Faster onset of action
Lower effective dose
Lower incidence of systemic S.E.
Inhalational Drug Delivery Devices
Metered – Dose Inhaler (MDI)
Dry powder inhaler
Soft mist inhaler
Nebulizer: Jet & Ultrasonic
use of spacer and valve holding chamber with MDI?
- Decrease the need for coordination of actuation with inhalation
- Decrease oropharyngeal deposition
- Increase pulmonary drug delivery.
MDI advantages and disadvantage?
advantages:
* medication delivery in 2 mins
* portable, durable
* low med dose needed
disadvantage
* techinque / coordinatioon difficult
* Propellant may taste bad or irritate the airways
Proper MDI Technique?
Shake the inhaler well
Remove the cap.
2. Exhale all air away from the inhaler.
3. Place the mouthpiece into the mouth with lips closed tightly around the inhaler.
4. To deliver a dose, press down on the canister ONE TIME while inhaling a slow steady breath. A puff of medication is sprayed out of the inhaler into the mouth.
5. Hold your breath for 10 seconds.
6. Exhale from nose.
7. Wait 1-2 minute if the dose is to be repeated.
8. Recap the inhaler when you are finished.
9. Rinse your mouth with water esp. if the medication is inhaled corticosteroid.
what If a counter is not available on the inhaler?
For patients who can not hold their breath for 10 seconds?
the patient should count the number of puffs used, to determine when the inhaler is empty.
instruct them to hold their breath as long as possible.
adv and disadvantages of dry power inhalation
adv:
1. sweet taste have lactose which is less to caue lactose intolarance
2. easy to use
3. quick delivery of medicine
disadavn:
1. require cordnition
2. not used for children less thn 4 due to high inspirtaory colume
3. less stable after opeing
adv and disadv
of soft mist inhaler
adv
1. no dry power or propellet
2. better lung deposition
disadv
* require coodination
* challenge to assemble first time use
Adult-onset asthma related to
atopy, nasal polyps, aspirin sensitivity, occupational exposure, or recurrence of childhood asthma.
Ics poor adherence and no response to treatment due to?
The main reasons for poor adherence are: the slow onset of action and concerns about systemic SE.
• Considerable variability in response to ICS exists, with up to 40 % of patients not responding to ICS.
• This lack of response may be related to functional glucocorticoid-induced transcript 1 gene variant in some patients with asthma
Side effects of inhaled corticosteroids
oral candidiasis, cough, and dysphonia.Hoarseness
Decreasing the dose reduces the incidence of hoarseness. Low and medium dose ICS were reported to affect children growth velocity.
Systemic corticosteroids
When
Drugs
Dose
Route
Prednisolone & methylprednisolone
• acute asthma not responding to SABA
• Their onset of action is 4 - 12 hours, so they need to be started early in the course of acute attack.
The duration of therapy usually ranges from 3 - 10 days. Treatment with systemic corticosteroids should be continued until PEFR is ≥ 70% of the personal best measurement and asthma symptoms are resolved.
Early-Phase Response
Peaks 30-60 minutes post exposure, subsides 30-90 minutes later
Characterized primarily by bronchospasm
Increased thick sputum secretion with edema formation
Patient experiences wheezing, cough, chest tightness, and dyspnea
- Late-Phase Response
Characterized primarily by inflammation
Histamine and other mediators set up a self-sustaining cycle increasing airways reactivity causing hyper-responsiveness to allergens and other stimuli
Increased airway resistance leads to air trapping in alveoli and hyperinflation of the lungs
If airway inflammation is not treated or does not resolve, may lead to irreversible lung damage
Clinical Presentation & Diagnosis of asthma
Symptoms:
1. Wheezing
2. Shortness of breath (SoB)
3. Coughing (typically worse at night)
4. Chest tightness
Additional Symptoms:
* Anxiety and agitation
* In acute severe asthma, patients may have difficulty communicating in complete sentences
* Mental status changes (e.g., confusion, irritability, agitation)
* Bradycardia and Absence of wheezing may indicate impending respiratory failure
* Symptoms exacerbated by precipitating factors such as smoke or viral illness
* Symptoms often follow a pattern (e.g., worse at night, seasonal variations)
