Lower Respiratory Tract Drugs

COPD 

• Emphysema, chronic bronchitis

• Caused by chronic inflammation in respiratory tract due to exposure to irritants (tobacco smoke, environmental pollutants)

• Treatment: Limit exposure to irritants; increase PO fluid intake; breathing exercises; medications—same as asthma treatment

ASTHMA

• Reactive airway disorder—bronchospasm, difficulty breathing

• Mast cell overreactivity—histamine, cytokines, eosinophils released which causes airway edema, smooth muscle constriction, oversecretion of mucus

• Treatment: Avoidance of triggers; management of allergies; avoidance of drugs (ASA, NSAIDS, Beta blockers) that can worsen symptoms

ALPHA & BETA ADRENERGIC AGONISTS

• Albuterol (Proventil, Ventolin)
• Used for bronchodilation
• Stimulates Beta receptors
• Side effects: Beta 1 stimulation (tachycardia, nervousness)
• Terbutaline—similar drug (also used for preterm labor)
• Levobuterol (Xopenex)—similar to albuterol; fewer cardiac side effects; expensive
• Isoproterenol (Isuprel)—Beta 1 & Beta 2 stimulation
• Can be given by IV for severe asthma attacks

• Epinephrine (Adrenalin)
• Stimulates Alpha 1, Beta 1, Beta 2 receptors
• Produces bronchodilation
• Tachycardia, elevates blood pressure; risk of arrhythmias

ANTICHOLINERGICS

• Ipratropium (Atrovent)—Prototype drug
• Prevents bronchoconstriction (end result = bronchodilation)
• Side effects: decreased SLUDGE (dry mouth common)
• Use before inhaled steroid if using dual therapy
• Combination with albuterol=Combivent inhaler

METHYLXANTHINES

• Theophylline (Theo-Dur) & aminophylline—chemically related
• Similar to caffeine—side effects similar
• Narrow therapeutic window
• Not recommended in people with cardiac, renal, hepatic disease or seizures
• Long-acting; mostly used in maintenance of stable asthma

LEUKOTRIENE RECEPTOR ANTAGONISTS

• Montelukast (Singulair)—Prototype drug
• For maintenance/prophylactic therapy of asthma
• Administered by PO route; long-acting
• Decreases inflammatory response; decreases bronchoconstriction
• Few serious side effects; not indicated for acute asthmatic attacks

GLUCOCORTICOIDS (AKA STEROIDS)

• Indicated for acute exacerbations of COPD or asthma
• Action: Decreases inflammatory response
• Many side effects: Elevated blood glucose, increased risk of infection; high doses must be tapered over 1-2 weeks (risk of adrenal suppression); weight gain; fluid retention; osteoporosis & cataracts with long-term therapy
• Systemic effects less with inhaled corticosteroids
• Most common side effect with inhaled: thrush
• Prevent thrush by rinsing mouth after each use

CROMOLYN & NEDOCROMIL

• Cromolyn (Intal)—Prophylactic treatment of asthma
• Chronic therapy; available by PO route
• Inhibits release of histamine
• Side effects:  rebound bronchospasm if abruptly discontinued
• Commonly used in children with asthma

Upper Respiratory System Drugs

Upper Respiratory Disorders:
 Involves nasopharynx, pharynx, larynx, sinuses: Colds, rhinitis, sinusitis, pharyngitis

• ANTIHISTAMINES
• Block H1 and/or H2 receptors 
• Side effects: Decreased SLUDGE (anticholinergic), drowsiness
• Prototype drug: Diphenhydramine (Benadryl)—1st generation—PO, injectable (can be used for emergencies)
• 2nd generation antihistamines: Cetirizine (Zyrtec), fexofenadine (Allegra), loratidine (Claritin)—available only by PO

• DECONGESTANTS
• Alpha adrenergic effects
• Administered by nasal spray, PO
• Drugs: Ephedrine, pseudoephedrine (Sudaphed), phenylephrine (Neo-Synephrine), oxymetazoline (Afrin)—spray
• Side effects: Rebound congestion with overuse of spray; systemic: elevated BP, elevated blood glucose; dysrhythmias; avoid stimulants

• INTRANASAL GLUCOCORTICOIDS
• Systemic side effects rare; may cause nasal dryness
• Drugs: Fluticasone (Flonase), Triamcinolone (Nasacort)

• ANTITUSSIVES
• Suppress cough reflex
• Prototype drug: Dextromethorphan (Robitussin, Delsym)
• Available OTC
• Intoxication at high doses

• EXPECTORANTS
• Liquify sputum for easier production with coughing
• Need to increase PO fluid itake
• Drug: Guaifenesin (Robitussin, Mucinex)

Pneumothorax

Accumulation of air in the pleural space.
Can occur spontaneously, w/out apparent reason, as a complication of preexisting lung disease, as a result of blunt or penetrating trauma to the chest or from thoracentesis.

Manifestation:
dyspnea, tachycardia, tachypnea, absent breath sounds or diminished, hyperesonant percussion on affected side, chest pain, anxiety, shock (late symptoms)

TENSION PNEUMOTHORAX (expanding): hypotension, shock, tracheal deviation (late but definitive sign), distended neck veins

Treatment:
chest tubes to allow the lung to re-expand; low-level suction helps reestablish negative pressure
large bore needle or plastic IV cath may be inserted thru the chest wall as emergency tx of tension pneumothorax.

Pleural Effusion

Collection of excess fluid in the pleural space. Either from systemic or local cause.
Pleural space normally contains 10-20 mL of serous fluid.

Systemic disorder that may lead to pleural effusion:

• heart failure
• renal or liver disease
• connective tissue disorder
• RA
• SLE

Local conditions that may lead to pleural effusion:

• pneumonia
• atelectasis
• TB
• lung cancer
• trauma

Manifestations:
diminished or absent breath sounds, dyspnea (difficult or labored breathing), pain (early sign), dull percussion

Treatments:
thoracentesis
treat cause

Pneumonia

@risk:
people over 65 with chronic cardiac or respiratory conditions, dm, alcoholism or other chronic diseases
immunocompromised people
chronic renal failure
people receiving chemotherapy

Prevention is a key component in managing pneumonia.
Pneumonia and flu vaccine. Revacination of pneumonia vaccine recommended for age >65 and who were immunized 5 years previously. Flu vaccine is yearly.

S/S:
fever, SOB, purulent sputum, rhonchi, crackles, pain, labored breathing
Vitals: increased HR, respiratory rate and temperature, decrease spO2, 
Elderly and immunocompromised: decrease LOC may be the only symptoms

Medications:
Antibiotics to eradicate the infection, culture 1st to identify the right antibiotics to be prescribed
Bronchodilators yp reduce bronchospasm and improve ventilation
agent to break up mucus or reduce its viscosity i.e mucomyst

Treatments:
increase fluid intake to 2500-3000 mL per day - to liquify secretion, making it easy to expectorate and cough up. IV fluids and nutrition
Incentive spirometry to promote deep breathing, coughing and clearance of respiratory secretions.
Endotracheal suctioning if cough is ineffective
Bronchoscopy can also be use to perform pulmonary toilet and remove secretions
Oxygen therapy
Chest physiotherapy
Promote rest to reduce metabolic and oxygen needs

Priority Nursing Diagnosis:
Ineffective airway clearance
Ineffective breathing pattern
Activity intolerance

Considerations:
High Fowler position promotes lung expansion
frequent position change and ambulation facilitate movement of secretions
Coughing, deep breathing and suctioning help clear airways
A liberal fluid intake helps liquify secretions, facilitating clearance

Test 2 outline for respiratory meds

Bronchodilators:

• Anticholinergic: ipatropium(atrovent), itotropium(spiriva)
• first line unless contraindicated, dry mouth is the side effect
• Beta-2 agonist: albuterol, levalbuterol
• work faster than anticholinergic, best for emergencies, stimulate CNS is the side effects
• Methylxantines: Theodur, it also increases mucociliary action
• side effects: toxicity possible, n/v, seizures, insomnia

 Corticosteroids: decrease inflammation, increase sensitivity to cathecolamines

• Systemic: Prednisone, Hydrocortisone, Methylprednisolone
• Many side effects such as hyperglcemia,infection, tachycardia, easy bruising, weight gain
• Inhaled: fluticasone, beclamethasone
• for COPD maintenance, less side effects than systemic; rinse mouth after each use to prevent oral thrush

AntiHistamines:

• 1st generation: Benadryl; sedating, drowsiness, dry mouth
• 2nd generation: Claritin, Allegra; less sedating than 1st gen

Mucolytics: decrease thickness of mucous i.e Mucinex

Influenza

Cause: viral
Droplet transmission; can lead to pneumonia 
Symptoms: malaise, fever, cough, sore throat
Treatment: symptom relief, rest
Prevention: vaccination, isolation, hygiene
Tamiflu & Relenza shorten duration and decrease symptoms
Vaccinate annually (different strains)

Acute Bronchitis

Inflammation of the bronchi.
Typically follows a viral upper respiratory infection
can be caused by bacteria or viruses
Common in older adult

Risk Factors:
immunocompromise and cigarette smoking

Manifestations:
nonproductive coughs that later become productive
chest pain
moderate fever
malaise

Treatment:
A chest x-ray may be ordered to rule out pneumonia, because the presenting manifestations can be similar.
rest, increased fluid intake, stop smoking
aspirin or acetaminophen to relieve fever and malaise
antibiotics for bacterial infection
OTC expectorant cough medication i.e mucinex or delsym

Book info:
The diagnosis of acute bronchitis typically is based on the history and clinical presentation. A chest x-ray may be ordered to rule out pneumonia, because the presenting manifestations can be similar. Other diagnostic testing and hospitalization are rarely indicated. Treatment is symptomatic and includes rest, increased fluid intake, and the use of aspirin or acetaminophen to relieve fever and malaise. Many physicians prescribe a broad-spectrum antibiotic such as erythromycin or penicillin, because approximately 50% of acute bronchitis is bacterial in origin. An expectorant cough medication is recommended for use during the day and a cough suppressant for night to facilitate rest.

Thoracentesis

Done to obtain a specimen of pleural fluid for diagnosis
used as a procedure to remove pleural fluid (pleural effusion) or instill medication
fluid removed is limited to 1200-1500 mL at one time to reduce the risk of cardiovascular collapse from rapid removal of too much fluid.

Pre-op:
requires informed consent
upright position,leaning forward w/ arms and head supported on anchored overbed table. This position spreads the ribs, enlarging the intercostal space for needle insertion.
coach patient to hold breathe or breathe out.

Post-procedure:
Chest x-ray is taken to check for pneumothorax, which is a possible complication for thoracentesis

Bronchoscopy

Direct visualization of the larynx, trachea and bronchi thru a bronchoscope to identify lesions, remove foreign bodies and secretions, obtain tissue for biopsy and improve tracheobronchial drainage.

Pre-op:
assess for hypersensitivity to anesthetics, antibiotics iodine or contract dyes
NPO for 8-12 hours
remove dentures, contact lenses, jewelry
assess vitals

Post-op:
assess for complication i.e laryngeal edema, bronchospasm, pneumothorax, cardiac dysrhythmias, bleeding
monitor for s/s of respiratory difficulty and hemoptysis (bloody sputum)
keep on NPO until gag reflex is back
no smoking for at least 6-8 hours cuz it may cause coughing and bleeding

Normal: blood-tinged sputum, hoarseness and sore throat
Report: pain, bleeding, respiratory difficulty

Obstructive sleep apnea

Intermittent absence of airflow through the mouth and nose during sleep. A serious and potentially life threatening disorder.

Manifestations:
loud, cyclic snoring
excessive daytime sleepiness, HA, irritability, restless sleep,
personality changes, depression, HTN, intellectual impairment, increases risk for heart failure

Risk Factors:
male, increasing age, obesity
large neck circumference
use of alcohol and CNS depressants

Treatments:
weight reduction, alcohol abstinence, improving nasal patency
avoid supine position for sleep
use of oral appliances designed to keep the mandible and tongue forward
tonsillectomy and adenoidectomy

CPAP/BiPAP - tx of choice

• positive pressure generated by an air compressor and administered thru a tight-fitting nasal mask splints the pharyngeal airway, preventing collapse and obstruction
• humidifier needed to prevent irritation and dryness
• BiPAP delivers higher pressure during inspiration and lower pressure during expiration, providing less resistance to exhaling
• continous usage at night
• adequate fluid intake to maintain moist mucous membrane

Atelectasis

partly or completely collapse lungs
not a disease but a condition associated w/ many respiratory disorders.

Cause:
obstruction of the bronchus, may be small or the entire lobe.
compression of the lung by pneumothorax, pleural effusion, or tumor; loss of surfactant or inability to keep an alveoli open

Manifestation:
for small atelectasis - diminished breath sounds over the affected area
bigger one - absent breath sounds, tachycardia, tachypnea, hypoxemia, dyspnea, cyanosis, reduced chest expansion

do a chest x-ray or ct scan to determine cause

Tx:
prevention is important for high risk patients - chest physiotherapy
cough, deep breath, spirometry, chest therapy
bronchoscopy if there is an obstruction that needs to be remove
antibiotic therapy to treat infectious cause (focus is treating the underlying cause)

position on the unaffected side to promote gravity drainage of the affected side
frequent position change, ambulation, coughing, deep breathing
fluids will help liquify secretions