Chapter 5 – Respiratory system A&P; age-related changes

Performance of respiration

• Controlled by respiratory muscles of the thorax
  • Diaphragm
  • Intercostal muscles
• Coordinated by respiratory centers of the brain and carotid arteries
• Respiratory centers respond to changes in:
  • Blood levels of oxygen
  • Carbon dioxide
  • Blood pH

Changes in upper respiratory structures

• Degenerative changes in connective tissue of the nose
• Diminished blood flow to the nose—nasal turbinates become smaller, therefore less effective warming, humidification, and filtering of air
• Thicker mucous in the nasopharynx
• Stiffening of the trachea 2˚ calcification of cartilage
• Blunted cough reflex
• Atrophy of laryngeal nerve endings

Changes in chest wall  and musculoskeletal structures

• Ribs and vertebrae become osteoporotic
• Costal cartilage calcifies
• Respiratory muscles weaken
• Structural changes:
  • Kyphosis
  • Increased a-P diameter
• Chest wall expansion is compromised

Changes in lung structure and function

• Ductasia—alveoli enlarge and walls become smaller
• pulmonary artery becomes wider, thicker, less elastic
• Number of capillaries diminishes
• Pulmonary capillary blood flow decreases
• Mucosal bed thickens
• Decreased elastic recoil

Consequences of age-related changes

• Increased residual volume
• Decreased vital capacity
• Premature airway closure → air trapping in lower airways (aka “hyper-inflation”)

Common upper respiratory tract pathologies

• Common cold
• Seasonal rhinitis
• Sinusitis
• Pharyngitis/laryngitis

Common cold

• Caused by multiple viruses
• Virus invasion prompts release of histamine, prostaglandins
• Inflammatory response occurs
• Swelling, mucous production

Seasonal rhinitis

• Aka “allergies” or “hay fever”
• Inflammation of nasal cavity
• Upper airways respond to a specific antigen

sinusitis

• Inflammation of lining of sinus cavities
• Severe pain due to pressure against bone (cannot stretch)
• Can travel up sinus passages to brain

Pharyngitis & laryngitis

• Infections of pharynx or larynx
• Bacterial or virus causes
• Frequently occur with influenza (viral cause)
• “injected” pharynx

    sign of infection,

    inflammation

Common Lower respiratory tract pathologies

• Asthma
• Chronic Bronchitis
• Emphysema

Asthma

• Airway inflammation
• Increased mucous secretion production
• Increased airway responsiveness/sensitivity
• Reversible airflow obstruction (usually)
• Eventually causes irreversible damage and scarring
• Often overlooked in the older client
• Treated with same types of medications as in younger patients

Symptoms of asthma

• Coughing
• Wheezing
• Shortness of breath
• Chest tightness
• Nocturnal dyspnea between 0400-0600
  • CHF nocturnal dyspnea occurs 1-2 hours after retiring

Emphysema

• Permanent destruction of the alveoli
• Collapse/narrowing of bronchioles
• Usually in older adults with long smoking history

Symptoms are slow in onset

• A destructive process
• Risk factors:  chronic bronchitis, irritation, pollutants, cigarette smoking
• May be considered normal age related changes initially
• Increased dyspnea, chronic cough develops
• Increased respiratory effort, fatigue, anorexia
• Recurrent infections, chf, cardiac dysrhythmias

Chronic bronchitis

• Cough and sputum production on most days
• Minimum of 3 months for at least 2 successive years, or,
• For 6 months during 1 year
• Treatment includes mobilizing secretions

A note on acute bronchitis…

• Acute inflammation of the bronchi
• Usually self-limiting
• Viral
• Similar to pneumonia:  productive cough, chills, lethargy, low grade fever
• Negative chest xray
• Treatment:  rest, humidification, cough suppressants, acetaminophen

Distinguishing types of COPD:  Blue bloater

• COPD with chronic bronchitis
• Increased mucous production
• Normal to decreased lung capacity
• Increased residual lung volume with air trapping
• Cyanosis and right heart failure
• Body responds by decreasing ventilation and increasing cardiac output

Distinguishing types of COPD:
Pink puffer

• COPD with severe emphysema
• Pink complexion
• Dyspnea
• Increased residual lung capacity
• Decreased elastic recoil
• High tidal volume
• Destruction of capillary bed
• Body compensates for destruction of pulmonary capillary bed by hyperventilation
• Retractions

Tuberculosis in the elderly

• Elderly the most vulnerable
• Drug resistant forms are prevalent
• Vulnerability enhanced by multiple risk factors:
  
  • Living in an institution, homeless
  • Exposure to drug-resistant forms
  • Previous infection
  • Diabetes
  • Use of immunosuppresive drugs including corticosteroids)
  • Malnutrition
  • Renal failure

Treatment of tuberculosis

• Isoniazid—prevent active disease once infected
• Rifampin
• Side effects can be significant
• Interrupting treatment can create drug resistant form

Lung cancer in the elderly

• More common in the young-old
• Initial symptoms are vague and mimic other pulmonary illnesses
• Chest xray initial diagnostic test
• Older, debilitated patients may not be surgical candidates
• Chemotherapy
• Radiation
• Palliative care

Respiratory infections: risk factors

• History nosocomial pneumonia
• COPD
• Recent hospitalization, institutionalization
• Smoking
• Hyperglycemia
• Use of immunosuppressants and/or antibiotics and/or oxygen therapy
• Recent antibiotic use
• Eating dependency

Pneumonia symptoms
in the elderly

• Cough
• Fever
• Sputum production
• Prodromal headache, myalgia, lethargy
• Changes in behavior and mental status
• New onset tachycardia and tachypnea
• Change in function