Unit 3: Medications Affecting the Respiratory System

What is the primary pathophysiology of asthma as defined in Chapter 16?

A chronic inflammatory disorder characterized by intermittent and reversible airflow obstruction of the bronchioles.

Name the two primary mechanisms by which airway obstruction occurs in asthma.

Inflammation and airway hyper-responsiveness leading to bronchoconstriction.

Medication management for airflow disorders typically addresses which two physiological issues?

Inflammation and bronchoconstriction.

Classify Albuterol and Levalbuterol based on their onset and duration of action.

Short-Acting $\beta_{2}$ Agonists (SABAs).

Classify Salmeterol and Formoterol based on their duration of action.

Long-Acting $\beta_{2}$ Agonists (LABAs).

What is the expected pharmacological action of $\beta_{2}$ adrenergic agonists on bronchial smooth muscle?

Selective activation of $\beta_{2}$ receptors resulting in bronchodilation.

Besides bronchodilation, what effect do $\beta_{2}$ agonists have on histamine and ciliary motility?

They inhibit histamine release and increase ciliary motility.

Which specific medication is used for the short-acting prevention of exercise-induced asthma episodes?

Albuterol (inhaled).

Under what circumstance is oral Albuterol indicated?

Long-term control of asthma.

Why might a client taking oral $\beta_{2}$ agonists experience tachycardia and angina?

Activation of $\alpha_{1}$ receptors in the heart.

A client taking Albuterol reports a pulse increase of $25/min$. What action should they take?

Report the increase to the provider as it exceeds the $20$ to $30/min$ threshold.

Why do $\beta_{2}$ agonists cause skeletal muscle tremors?

Activation of $\beta_{2}$ receptors in skeletal muscle.

True or False: $\beta_{2}$ adrenergic agonists are contraindicated in clients with tachydysrhythmia.

True.

How do $\beta$-adrenergic blockers interact with $\beta_{2}$ agonists?

They negate the effects of both medications.

Which antidepressant classes increase the risk of tachycardia and angina when taken with $\beta_{2}$ agonists?

MAOIs and tricyclic antidepressants.

When a client is prescribed an inhaled $\beta_{2}$ agonist and an inhaled glucocorticoid, which should be used first?

The $\beta_{2}$ agonist.

What is the rationale for administering a bronchodilator before a glucocorticoid?

Bronchodilation enhances the absorption of the glucocorticoid.

What is the standard dosing frequency for long-acting $\beta_{2}$ agonist inhalers like Salmeterol?

Every $12$ hours.

True or False: LABAs like Formoterol should be used alone for asthma management.

False; they must be prescribed in combination with an inhaled glucocorticoid.

What should a nurse evaluate to determine the effectiveness of Albuterol for an acute exacerbation?

Absence of shortness of breath, clear breath sounds, and absence of wheezing.

What is the prototype medication for Methylxanthines?

Theophylline.

What is the therapeutic range for Theophylline blood levels?

$10$ to $20\ \mu g/mL$.

What are the manifestations of mild Theophylline toxicity?

GI distress and restlessness.

What severe complications can occur at high therapeutic levels of Theophylline?

Dysrhythmias and seizures.

Which substance increases the CNS and cardiac adverse effects of Theophylline?

Caffeine.

If a client on Theophylline experiences a seizure, which medication is used for control?

Diazepam.

How do Cimetidine and Ciprofloxacin affect Theophylline levels?

They increase Theophylline levels.

How do Phenobarbital and Phenytoin affect Theophylline levels?

They decrease Theophylline levels.

What instruction should be given regarding sustained-release Theophylline preparations?

Do not chew or crush them; swallow them whole.

What is the pharmacological action of inhaled anticholinergics like Ipratropium?

They block muscarinic receptors of the bronchi, resulting in bronchodilation.

Identify the primary therapeutic use for Ipratropium and Tiotropium.

Relieving bronchospasm associated with COPD.

What are the common local adverse effects of inhaled anticholinergics?

Dry mouth and hoarseness.

In which client populations should Ipratropium be used cautiously due to its anticholinergic effects?

Clients with narrow-angle glaucoma or benign prostatic hyperplasia.

Ipratropium is contraindicated in clients with an allergy to which substance?

Atropine.

What teaching should be provided to a client using two different inhaled medications?

Wait at least $5$ minutes between the two medications.

Identify the prototype inhaled glucocorticoid.

Beclomethasone.

Identify the prototype oral glucocorticoid.

Prednisone.

What is the expected pharmacological action of glucocorticoids in the respiratory system?

Prevent inflammation, suppress mucus production, and promote responsiveness of $\beta_{2}$ receptors.

True or False: Inhaled glucocorticoids provide immediate relief for an acute asthma attack.

False; they are used for long-term prophylaxis.

Which medication is indicated for the short-term treatment of status asthmaticus?

IV glucocorticoids (Hydrocortisone or Methylprednisolone).

What complication is a client at risk for if they do not rinse their mouth after using Beclomethasone?

Oropharyngeal candidiasis.

What intervention is used to treat oral candidiasis caused by glucocorticoid use?

Nystatin oral suspension.

Using Prednisone for $10$ days or more can lead to which endocrine complication?

Suppression of adrenal gland function.

What dosing schedule is recommended for oral Prednisone to minimize adrenal suppression?

Alternate-day dosing.

Clients on long-term glucocorticoid therapy should be monitored for which metabolic complication?

Hyperglycemia.

Why should clients on long-term glucocorticoids perform weight-bearing exercises?

To prevent bone loss.

What instruction should be given to a client on glucocorticoids regarding NSAID use?

Avoid NSAIDs to reduce the risk of peptic ulcer disease.

How do glucocorticoids affect the risk of infection?

They increase the risk; clients should avoid large crowds and practice hand hygiene.

What are the fluid and electrolyte complications associated with Prednisone?

Fluid retention (weight gain/edema) and hypokalemia.

What is the nursing action regarding the withdrawal of Prednisone?

Taper the dose; do not stop abruptly.

What is the pharmacological action of Leukotriene modifiers like Zafirlukast?

They suppress leukotrienes to reduce inflammation, bronchoconstriction, and mucus production.

Which Leukotriene modifier is associated with depression and suicidal ideation?

Montelukast.

What laboratory monitoring is required for Zileuton and Zafirlukast?

Liver function tests (LFTs) due to the risk of liver injury.

When should Montelukast be administered for general asthma control?

Once daily at bedtime.

How should Montelukast be timed for the prevention of exercise-induced bronchospasm?

Take $2$ hours before exercise.

Leukotriene modifiers (Zileuton/Zafirlukast) inhibit the metabolism of which anticoagulant?

Warfarin.

What is the expected pharmacological action of Opioid Antitussives like Codeine?

Suppression of cough through CNS action to increase the cough threshold.

What are the primary CNS adverse effects of Codeine?

Dizziness, lightheadedness, drowsiness, and respiratory depression.

Identify the nursing priority if a client's respiratory rate drops below $12/min$ while taking Codeine.

Stop the medication and be prepared to administer Naloxone.

How should a client be instructed to take Codeine to minimize GI distress?

Take the medication with food.

Identify the prototype non-opioid antitussive.

Dextromethorphan.

Dextromethorphan can cause high fever if used within $2$ weeks of which medication class?

MAOI antidepressants.

What is the pharmacological action of Guaifenesin?

It promotes increased cough production by increasing and thinning mucous secretions.

What is a critical nursing instruction for a client taking Guaifenesin to ensure effectiveness?

Take with a full glass of water and maintain high fluid intake.

Which respiratory condition requires caution when using Guaifenesin due to the risk of bronchospasm?

Asthma.

What is the prototype medication for Mucolytics?

Acetylcysteine.

Besides thinning secretions, what is the specific therapeutic use for Acetylcysteine via IV or oral routes?

Antidote for acetaminophen poisoning.

What sensory characteristic should the nurse warn the client about regarding Acetylcysteine?

It has an odor that smells like rotten eggs.

Identify two critical complications of Acetylcysteine when administered orally.

Aspiration and bronchospasm.

What is the pharmacological action of sympathomimetic decongestants like Phenylephrine?

Stimulation of $\alpha_{1}$-adrenergic receptors causing reduction in inflammation of nasal membranes.

What complication occurs from prolonged use of topical decongestants beyond $3$ to $5$ days?

Rebound congestion.

Why should clients with hypertension or coronary artery disease avoid oral decongestants?

They cause systemic vasoconstriction.

Identify a CNS adverse effect associated specifically with oral decongestants.

CNS stimulation (agitation, nervousness, uneasiness).

What is the pharmacological action of antihistamines on the $H_{1}$ receptors?

They block histamine release in small blood vessels, capillaries, and nerves.

Compare 1st generation and 2nd generation antihistamines regarding sedation.

1st generation (e.g., Diphenhydramine) causes significant sedation, while 2nd generation (e.g., Loratadine) is usually non-sedating.

Identify the common anticholinergic side effects of 1st generation antihistamines.

Dry mouth, constipation, and urinary retention.

Identify the specific risk and nursing action associated with IV Promethazine.

Risk of local tissue injury; monitor for extravasation and burning sensations.

Antihistamines are contraindicated in children under what age when specifically referring to Promethazine?

Under $2$ years of age.

Identify the prototype nasal glucocorticoid used for allergic rhinitis.

Mometasone.

How long might it take for a client with perennial allergic rhinitis to achieve maximum relief with Fluticasone?

As long as $21$ days.

What should the nurse instruct the client to do before administering a nasal glucocorticoid if their nasal passages are blocked?

Clear blocked nasal passages with a topical decongestant first.

Which medication is an inhaled long-acting $\beta_{2}$ agonist (LABA) used every $12$ hours?

Salmeterol.

Identify the prototype medication for 1st generation $H_{1}$ antagonists used for allergic reactions and insomnia.

Diphenhydramine.

Which medication acts to increase the cough threshold through CNS action but is non-opioid?

Dextromethorphan.