Lower Respiratory Tract
The bronchial tree ends in dilated sacs called alveoli
Gases to readily move between the blood and the inspired air
A semipermeable membrane allows:
-oxygen to enter the blood
-carbon dioxide and cellular waste products to leave the lungs
Autonomic Control of Airways
Bronchioles are lined with smooth muscle that controls amount of air entering lungs.
Diameter of airways controlled by autonomic nervous system.
Sympathetic branch
-activates beta2-adrenergic receptors and causes bronchodilation
Parasympathetic branch
-ca
Administration by Inhalation
Common route of administration for pulmonary drugs
Rapid and efficient
Rich blood supply allows for quick absorption and onset of action
Delivers drugs directly to sites of action
Inhalation versus Oral Therapy
Oral therapy
-longer duration of action
-frequent side effects
-tolerance may develop
Aerosol Therapy
Suspension of droplets or particles in a gas
Advantages:
-onset of action almost immediate
-drugs administered for local effect
-immediate relief of bronchospasm
-loosens thick mucus
-side effects are reduced; systemic effects can still occur
Disadvantage
Devices Used for Aerosol Therapy
Nebulizer
- Vaporizes liquid drug into fine mist
- Uses small machine and face mask
Metered-dose inhaler (MDI)
- Propellant delivers measured dose of drug
- Patient times inhalation to puffs of drug
Dry powder inhaler (DPI)
- Patient inhales powdered drug
Inhalers: Patient Education
For any inhaler prescribed, ensure that the patient is able to self-administer the medication
-provide demonstration and return demonstration
-ensure that the patient knows the correct time intervals for inhalers
-provide a spacer if the patient has diffi
Asthma
A chronic disease that has both inflammatory and bronchospasm components
Symptoms occur:
-from exposure to triggers
-upon exertion (exercise induced)
status asthmaticus
-prolonged attack
-a severe, life-threatening asthma attack that is refractory to usual treatment and places the patient at risk for developing respiratory failure
-4-5 nebulizer treatments back to back
-with beta adrenergic agonist, may drop potassium (h
Goals of asthma therapy
Asthma has both bronchoconstriction component and inflammation component
Goals of drug therapy are twofold:
-terminate acute bronchospasms in progress (quick-relief medications)
-reduce the frequency of asthma attacks (long-acting medications)
Quick relief medications for asthma
beta2-adrenergic agonists
anticholinergics
systemic corticosteroids
long acting asthma medications
inhaled corticosteroids
mast cell stabilizers
leukotriene modifiers
long-acting beta2-adrenergic agonists
methylxanthines
immunomodulators
Beta-Adrenergic Agonists for asthma
Most effective drugs for relieving acute bronchospasm
Activate beta2 receptors in bronchial smooth muscle to cause
bronchodilation
Agonists, or stimulators, of the adrenergic receptors in the sympathetic nervous system
-sympathomimetics
Range from ultrash
Beta-Adrenergic Agonists-SABA
Short-acting beta agonist (SABA) inhalers
-acute relief of bronchospasm
-Q4h
-given every COPD, every asthmatic, every resp. issue....
Examples:
-albuterol (Ventolin)
- sometimes given for hyperkalemia
-levalbuterol (Xopenex)
-pirbuterol (Maxair)
-metapro
Beta-Adrenergic Agonists-LABA
Long-acting beta agonist (LABA) inhalers
-Q 12h
-prophylaxis of bronchospasms
-never used for acute asthma attack, preventative only
Examples:
-arformoterol (Brovana)
-salmeterol (Serevent)
-formoterol (Foradil, Perforomist)
Black Box:
-increased risk of
Beta-adrenergic Agonists Nursing Role
Minimal systemic effects when administered by inhaler - fastest!
PO use may be associated with some degree of beta1 activation and increased heart rate, angina, arrhythmia
Some degree of tolerance may occur with chronic use
-increase dose, or *add second
Anticholinergics for asthma
quick relief med;
bronchodilator
Examples:
-ipratropium bromide (Atrovent)
-tiotropium (Spiriva)
MOA:
-block parasympathetic nervous system with bronchodilator effect
Use:
-relief of acute bronchospasm
-occasionally used as alternative or combined with be
Methylxanthines (Xanthine Derivatives)
Examples:
-theophylline (Theo-Dur)
-aminophylline (Truphylline)
(PO or IV)
Group of bronchodilators related to caffeine
-plant alkaloids
Narrow margin of safety; interact with numerous drugs
MOA:
-causes bronchodilation by relaxing smooth muscle in the ai
Xanthine Derivatives: Nursing Role
Contraindicated:
-coronary artery disease
-angina pectoris
-severe renal or liver disorders
-peptic ulcer
-BPH
-diabetes mellitus
Cautious use:
-cardiac disease
*Drug Interactions:
-cimetidine
-oral contraceptives
-allopurinol
-certain antibiotics
-influe
Corticosteroids for asthma
Potent anti-inflammatory drugs
-prevent activation of inflammatory cells and release of inflammatory mediators
Inhaled drugs of choice for long-term prophylaxis of asthma
-must be taken daily-takes several weeks for full effect
-systemic side effects rare
Inhaled Corticosteroids
Examples:
-beclomethasone dipropionate (Beclovent)
-budesonide (Pulmicort Respules)
-dexamethasone sodium -phosphate (Decadron Phosphate Respihaler)
-flunisolide (AeroBid)
-fluticasone (Flovent Diskus, Flonase)
-triamcinolone acetonide (Azmacort)
-cicleso
Role of the Nurse: Corticosteroids
Not recommended for pregnant or breast-feeding women
Primary purpose of inhaled corticosteroids is to
prevent
respiratory distress
-
do not use this medication during acute asthma attack
Patients should watch for signs and symptoms of simple infections
-r
Inhaled Corticosteroids + B2 Agonist
combination medication=
corticosteroid (reduces inflammation)
+
long-acting bronchodilator B2 agonist (relieves airway constriction)
ex: Symbicort (not mixed in nebulizer, pre-packaged)
not used acutely, long acting
Leukotriene Modifiers
Leukotrienes are mediators of immune response
-involved in allergic and asthmatic reactions
Leukotriene modifiers primarily used for asthma prophylaxis
-reduce inflammatory response
Oral medication when persistent asthma not controlled with other drugs
Leukotriene Modifiers
Examples & MOA:
montelukast (Singulair)
- most popular
-prevents airway edema and inflammation by blocking leukotriene receptors in airways
zafirlukast (Accolate)
montelukast (Singulair)
-blocks leukotriene receptors
zileuton (Zyflo CR)
-inhibits lipooxyg
Mast Cell Stabilizers
Examples:
-cromolyn (Intal)
-nedocromil (Tilade)
MOA:
-inhibit mast cells from releasing histamine and other chemical mediators
Use:
-safe for prophylaxis of asthma
-less effective than inhaled corticosteroids
-ineffective at relieving acute bronchospasm
Monoclonal Antibodies for Asthma Prophylaxis
First biologic therapy approved to treat asthma; attaches to specific receptor on a target cell or molecule
-attaches to receptor on immunoglobulin E (IgE)
-prevents the IgE-mediated release of inflammatory mediators
Example:
omalizumab (Xolair)
Use:
-giv
Mucolytics for Asthma****
Example:
-acetylcysteine (Mucomyst)
Use:
-Tylenol overdose
Contraindications/Caution:
-those with compromised cough ability
-asthmatics- can cause: bronchospasm (especially inhaled)
-IV- not for hepatic diseases; can produce anaphylactic side effects
-PO-
Pharmacotherapy of Chronic Obstructive Pulmonary Disease (COPD)
Obstructed airflow:
-commonly caused by chronic bronchitis, asthma
-in progressive stage, it leads to emphysema
Pharmacotherapy goals
-relieve symptoms
-avoid complications
-#1 cause is smoking
-pneumonia can lead to sepsis
Treatment of COPD
Bronchodilators
to open airways
-ipratropium (Atrovent)
-tiotropium (Spiriva)
-SABAs (acute) and LABAs (prevention)
Anti-inflammatories
-inhaled corticosteroids
-
roflumilast (Daliresp)
- long-acting; only medicine of its kind for COPD
--PDE4 (phosphodies
COPD: Nursing Implications
Encourage patients to take measures that promote a generally good state of health so as to prevent, relieve, or decrease symptoms of COPD
-avoid exposure to conditions that precipitate bronchospasm (allergens, smoking, stress, air pollutants)
-adequate fl
Which medication will the nurse teach a patient with asthma to use when experiencing an acute asthma attack?
A. albuterol (Ventolin)
B. salmeterol (Serevent)
C. theophylline (Theo-Dur)
D. montelukast (Singulair)
A. albuterol (Ventolin)