1. Drugs Affecting the Lower Respiratory System

2. Gas Exchange/Oxygenation: Lower Respiratory System
Oxygen Transport:

3. Lower Respiratory Tract

4. Physiology
The lower respiratory tract is almost sterile because of various defense mechanisms in the upper respiratory system.
Protective mechanisms
All the tubes in the lower airway contain goblet cells, which secrete mucus to entrap any particles.
Microorganisms and other foreign bodies are removed from the air by tiny hair-like structures called cilia.
Gas exchange, perfusion, and respiration
Lung tissue receives its blood supply from the bronchial artery, which branches directly off the thoracic aorta.
Ventilation
The act of breathing is controlled by the central nervous system (CNS).

5. Lower Respiratory Disorders
COPD – chronic obstructive pulmonary disorder
Airway obstruction with increased resistance of airflow to lung tissues
Four major lung disorders:
Chronic bronchitis Bronchiectasis – irreversible damage to bronchioles
Emphysema – irreversible damage to alveoli
Asthma – reversible, common in childhood
Restrictive pulmonary disease
Decrease in total lung capacity from fluid accumulation or loss of elasticity of the lung
Examples:
Pulmonary edema
Pulmonary Fibrosis, genetic e.g. Cystic Fibrosis
Lung tumors
Thoracic deformities (scoliosis)
Thoracic muscular disorders e.g. Myasthenia Gravis

6. Pathophysiology Acute bronchitis is caused most frequently by viruses.
Chronic bronchitis is long-standing, largely irreversible inflammation of the bronchial tree.
Asthma is a disorder characterized by recurrent episodes of bronchospasm, bronchial muscle spasm that leads to narrowed or obstructed airways.
Instructor Notes:
Physiology
The lower respiratory tract is virtually sterile because of the various defense mechanisms in the upper respiratory system.
Protective mechanisms
All the tubes in the lower airway contain goblet cells, which secrete mucus to entrap any particles.
Microorganisms and other foreign bodies are removed from the air by tiny hair-like structures called cilia.
Gas exchange, perfusion, and respiration
Lung tissue receives its blood supply from the bronchial artery, which branches directly off the thoracic aorta.
Ventilation
The act of breathing is controlled by the central nervous system (CNS).

7. Pathophysiology (cont’d)
Emphysema is an abnormal distention of the lungs with air characterized by loss or degeneration of elastic tissue, disappearance of capillary walls, and breakdown of the alveolar walls.
Pneumonia is an inflammation of the lungs. It can be caused by bacterial or viral invasion of the tissue or by aspiration of foreign substances into the lower respiratory tract.
Cystic fibrosis is a hereditary disease that affects the functioning of the body’s exocrine glands: the mucus-secreting and sweat glands.

8. Pathophysiology of Asthma
Primary response is chronic inflammation from exposure to allergens or irritants.
This leads to airway hyper-responsiveness and acute airflow limitations
Inflammatory mediators cause early-phase response.
Inflammatory mediators cause early-phase response.
Vascular congestion
Edema formation
Production of thick, tenacious mucus
Bronchial muscle spasm
Thickening of airway walls

9. Pathophysiology of Allergic Asthma
Asthma is triggered when an irritant cross-links antigen receptors on mast cells.
Histamine and other inflammatory responses are triggered

10. Factors Causing Obstruction in Asthma
Bronchioles become occluded by muscle spasms, swollen mucosa, and mucus in the lumen.

11. Clinical Manifestations of Asthma
Unpredictable and variable
Recurrent episodes of wheezing, breathlessness, cough, and tight chest
May be abrupt or gradual
Lasts minutes to hours
Expiration may be prolonged.
Inspiration-expiration ratio of 1:2-4
Bronchospasm, edema, and mucus in bronchioles narrow the airways.
Air takes longer to move out.

12. Clinical Manifestations
Signs of hypoxemia
↑ pulse and blood pressure
Restlessness
↑ anxiety
Inappropriate behavior
Pulsus paradoxus (drop in systolic BP during inspiratory cycle >10 mm Hg)

13. Complications Life-threatening asthma pO2 levels drop
Too short of breath (dyspneic) to speak
Perspiring profusely
Drowsy/confused
Require hospital care and often admitted to ICU

14. Mucolytic Drugs Prototype drug: acetylcysteine (Mucomyst)
Mucolytics break down mucus.
The drugs can be administered by a nebulizer or by direct instillation into the trachea.
Mucolytics usually are reserved for patients who have major difficulty mobilizing and coughing up secretions.
Prototype drug:
acetylcysteine (Mucomyst)

15. Acetylcysteine: Core Drug Knowledge
Pharmacotherapeutics
Used to liquefy the thick, tenacious secretions.
Pharmacodynamics
It splits disulfide bonds that are responsible for holding the mucous material together.
Contraindications and precautions
Hypersensitive
Adverse effects
Bronchospasm, bronchoconstriction, chest tightness, a burning feeling in the upper airway, and rhinorrhea
Unpleasant (sulfur, rotten egg) smell with

16. Acetylcysteine: Planning and Interventions
Maximizing therapeutic effects
Administer an inhaled beta-agonist before administering acetylcysteine.
Minimizing adverse effects
Inform the patient that nebulization may produce an initially disagreeable odor, but that this odor is transient.

17. Bronchodilators Prototype drug: albuterol (Proventil, Ventolin)
Bronchodilators are drugs used to
dilate the airways.
Inhalation is the most frequent method using metered-dose inhalers (MDIs) or dry-powder inhalers (DPIs).
Beta-agonists (sympathomimetics)
One of the actions of beta stimulation in the sympathetic nervous system is dilation of the bronchi and increased rate and depth of respiration.
Prototype drug: albuterol (Proventil, Ventolin)

18. Metered Dose Inhalers

19. Nebulizers

20. Albuterol: Core Drug Knowledge
Pharmacotherapeutics
Bronchodilator in managing Chronic Airway Limitation disease and asthma
Pharmacodynamics
It selectively stimulates receptors of the smooth muscle in the lungs, the uterus, and the vasculature that supplies the skeletal muscle.
Side effects
Tachycardia, palpitations, anxiety, tremors, headache, insomnia, muscle cramps, and upset stomach.

21. Albuterol: Nursing Diagnoses and Outcomes
Anxiety related to sympathomimetic effects of albuterol administration
Ineffective Tissue Perfusion: Cardiopulmonary related to rebound bronchoconstriction caused by overuse of albuterol

22. Albuterol: Teaching, Assessment, and Evaluation
Patient and family education
Teach patients that inhaled albuterol is a “rescue drug.”
Teach patients how to use an MDI.
Explain the importance of limiting caffeine intake.

23. Anticholinergic Agents
Inhaled anticholinergic drugs are considered first-line treatment for patients with Chronic Airway Limitation (CAL).
Anticholinergic agents diminish the effect of acetylcholine.
In the respiratory system, use of inhaled anticholinergic drugs stops bronchoconstriction.
Prototype drug:
ipratropium bromide
(Atrovent)

24. Ipratropium Bromide: Core Drug Knowledge
Pharmacotherapeutics
Used for maintenance treatment of bronchospasm
Pharmacodynamics
Antagonizes the action of acetylcholine by blocking muscarinic cholinergic receptors
Side effects
Cough, hoarseness, throat irritation
Adverse effects
Paradoxic acute bronchospasm

25. Ipratropium Bromide: Nursing Concerns
Risk for Injury (anaphylactic reactions) related to allergies to soybeans, legumes, or soya lecithin.

26. Ipratropium Bromide: Teaching, Assessment, and Evaluation
Patient and family education
Advise patients that ipratropium is used prophylactically (prevention).
Remind patients that overuse of ipratropium may induce adverse effects.

27. Xanthine Derivatives Prototype drug: *theophylline (Theodur)
The xanthine derivatives, including theophylline, aminophylline, and caffeine, come from a variety of naturally occurring sources.
They are excellent bronchodilators but do not work as rapidly as beta-adrenergic agonist drugs.
Prototype drug:
*theophylline (Theodur)
*Not on drug list

28. Theophylline: Core Drug Knowledge
Pharmacotherapeutics
Indicated for the symptomatic relief or prevention of bronchial asthma and reversal of bronchospasm
Administered orally and on a routine basis for maintenance
Pharmacodynamics
It is believed that bronchodilation is caused by inhibition of phosphodiesterase.
Adverse effects
Adverse effects related to theophylline use are related directly to serum levels of the drug.

29. Theophylline: Nursing Concerns
Disturbed Sensory Perception: CNS effects of irritability, insomnia, and dizziness.
Ineffective Tissue Perfusion: Cardiopulmonary related to cardiac effects of the drug.
Risk for Injury related to headache, GI effects, and CNS effects.

30. Anti-Inflammatory
In addition to bronchodilators, anti-
inflammatory agents are used to manage
respiratory disorders, especially asthma.
Inhaled glucocorticoid steroids
Glucocorticoid steroids are the most effective anti-inflammatory drugs available for managing respiratory disorders.
Inhaled corticosteroid (ICS) agents have become first-line treatment for persistent asthma.
Prototype drug: fluticasone/salmeterol (Advair), beclomethasone (Q-var)

31. fluticasone/salmeterol: Core Drug Knowledge
Pharmacotherapeutics
Used to prevent bronchospasm
Used for maintenance (routine – not PRN)
Pharmacodynamics
Inhibit the production of leukotrienes and prostaglandins through interference with arachidonic acid metabolism.
Side/Adverse effects
Sore throat, hoarseness, coughing, dry mouth, and pharyngeal and laryngeal fungal infections

32. fluticasone/salmeterol: Nursing Concerns
Impaired Verbal Communication related to dysphonia and cough
Risk for oral infection related to immunosuppression

33. fluticasone/salmeterol: Core Drug Knowledge
Patient and family education
Patient education is important for inhaled steroid therapy.
Importance of daily use, regardless of the absence of symptoms
Rinse mouth after use of fluticasone/salmeterol (Advair)

34. Leukotriene Receptor Antagonist
Leukotrienes are inflammatory mediators that are powerful bronchoconstrictors and vasodilators.
Leukotrienes have been identified as important mediators in the pathology and symptomatology of asthma.
They are used for prevention of asthma attacks.
Prototype drugs:
*montelukast (Singulair)
*Not on drug list

35. Montelukast : Core Drug Knowledge
Pharmacotherapeutics
Prophylaxis or treatment of chronic asthma
Pharmacodynamics
Blocks receptors for the leukotrienes bound to the amino acid cysteine
Side/Adverse effects
Headache, gastritis, pharyngitis, and rhinitis
Numerous drug interactions

36. Montelukast : Teaching, Assessment, and Evaluation
Patient and family education
Explain that montelukast is used in maintenance therapy.
Encourage patients to take nonnarcotic analgesics if headache occurs.

37. Challenge Question
Acetylcysteine (Mucomyst) for respiratory use is administered by:
A. Inhalation
B. SC
C. Oral
D. IV
Inhalation.
Oral use is indicated for acetominophen overdose.

38. Challenge Question
Albuterol is given for acute exacerbation of Chronic Airway Limitation (CAL) or asthma.
A. True
B. False

39. Challenge Question
Patients using inhaled steroids are at a high risk for developing
Oral bacterial infection
Oral viral infection
Oral fungal infection
C. Oral fungal infection

40. Question
Montelukast is used for A. Prophylaxis – prevention of attacks B. Acute attack C. Infection D. All of the above

41. Match Drug + Administration
Routine
PRN
Ipratroprium (Atrovent)
Fluticasone/
salmeterol (Advair)
Albuterol (Proventil)

42. Homework Activity - 1: Orientation to Shadow Health Digital Clinical Experience (DCE)
You will need to be in a private place or use head phones for this activity due to the audio/video component.
CLASS PIN:  February
1. Log in and create an account. There is no cost to you for this activity. 
2. Use Class PIN above to find our class account.
3. Complete the Shadow Health DCE Orientation (Due by March 11th)

43. Homework Activity – 2 Quiz #6: The Respiratory System