Quiz 5

Interpreting an ABG (Arterial Blood Gas)

• pH: Measures acidity/alkalinity (normal: 7.35-7.45)

• PaCO₂: Reflects respiratory function (normal: 35-45 mmHg)

• HCO₃: Reflects metabolic function (normal: 22-26 mEq/L)

• PaO₂: Indicates oxygenation (normal: 80-100 mmHg)

• SaO₂: Percentage of hemoglobin saturated with oxygen (95-100% normal)

Pulse Oximetry

measures oxygen saturation (SpO2)

heart rate should match the pulse on the oximeter to ensure accuracy

Noninvasive )2 Delivery Methods

• Nasal cannula: 1-6 L/min (low flow)

• Simple face mask: 6-10 L/min

• Non-rebreather mask: 10-15 L/min (high flow, emergencies)

• Venturi mask: Delivers precise FiO₂ (COPD patients)

• Face tent: Used for claustrophobic patients or those with facial trauma

Education for Home Oxygen Use

• No smoking/open flames near O₂

• Store tanks upright

• Avoid petroleum-based products near O₂

• Properly clean equipment

Auscultated Breath Sounds and Disorders

• Wheezing: High-pitched, associated with asthma, COPD, bronchoconstriction

• Crackles: Popping/bubbling, seen in pneumonia, CHF, pulmonary edema

• Rhonchi: Coarse, snoring-like, common in bronchitis, mucus accumulation

gas exchange location

occurs at the alveoli-capillary membrane in the lungs

ventilation

air movement in/out of lungs

perfusion

blood flow to alveoli for gas exchange

respiration

cellular gas exchange process

hemoptysis

coughing up blood

adventitious breath sounds

abnormal lung sounds

retractions

visible inward pulling of intercostal muscles

turbinates

warm, humidify, and filter air

epiglottis

prevents aspiration

alveoli

site of gas exchange

asthma

• Pathophysiology: Chronic airway inflammation leading to bronchoconstriction

• Clinical Manifestations: Wheezing, dyspnea, coughing, chest tightness

COPD

• Pathophysiology: Chronic obstruction due to emphysema and chronic bronchitis

• Clinical Manifestations: Chronic cough, dyspnea, barrel chest, wheezing

• Risk Factors: Smoking (leading cause), pollution, occupational exposure

tuberculosis

• Pathophysiology: Mycobacterium tuberculosis infection causing lung granulomas

• Clinical Manifestations: Night sweats, weight loss, hemoptysis, chronic cough

Diagnostic Procedures

• Sputum culture/study: Identifies infection type (TB, pneumonia, etc.)

• Thoracentesis: Removes excess pleural fluid for analysis

Influenza

• Pathophysiology: Viral infection causing airway inflammation

• Clinical Manifestations: Fever, chills, myalgia, cough, fatigue

• High-risk groups: Elderly, infants, immunocompromised

• Management: Antivirals (oseltamivir), rest, hydration

• Patient education: Hand hygiene, avoid close contact

• Vaccination: Recommended annually

• Infectious period: 1 day before symptoms → 5-7 days after

• Preventing spread: Droplet precautions, handwashing

Pneumonia

• Cyanosis

• Confusion

• Tachypnea

• Decreased SpO₂

tuberculosis isolation precautions

• Airborne precautions:

  • Negative pressure room

  • N95 mask for staff

Other Isolation Precautions

• Airborne: TB, measles, varicella

• Droplet: Flu, pertussis, meningitis

rhinitis

• Pathophysiology: Inflammation of nasal mucosa

• Clinical Manifestations: Sneezing, congestion, rhinorrhea

• Treatment:

  • 1st-gen antihistamines: Sedating (diphenhydramine)

  • 2nd-gen antihistamines: Non-sedating (loratadine, cetirizine)

  • Nasal decongestants:

    • Mechanism: Vasoconstriction (phenylephrine, oxymetazoline)

    • Teaching: Do not use for >3 days (risk of rebound congestion)

  • Intranasal corticosteroids: Fluticasone (reduces inflammation)

obstructive sleep apnea

• Risk Factors: Obesity, male gender, large neck circumference

• Pathophysiology: Repeated upper airway collapse

• Diagnosis: Sleep study (polysomnography)

asthma

• Clinical Manifestations: Wheezing, shortness of breath, cough

• Pathophysiology: Airway hyperresponsiveness, bronchoconstriction

• Management: Avoid triggers, inhaled corticosteroids, bronchodilators

• Medications:

  • Beta-agonists (albuterol): Bronchodilation

  • Corticosteroids (fluticasone): Reduce inflammation

emphysema

• Pathophysiology: Alveolar destruction → air trapping, loss of elasticity

• Clinical Manifestations: Barrel chest, pursed-lip breathing, dyspnea

cystic fibrosis

• Pathophysiology: Genetic disorder causing thick mucus production

• Clinical Manifestations: Chronic lung infections, malnutrition, cough

• Management: Chest physiotherapy, pancreatic enzyme replacement

• Cure?: No cure, but treatments improve life expectancy

lung cancer risk factors

smoking (#1 cause), radon exposure, asbestos, family history

COPD

• Types: Chronic bronchitis & emphysema

• Risk Factors:

  • Leading cause: Smoking

  • Other causes: Air pollution, occupational hazards

• Immunization Recommendations: Annual flu vaccine, pneumococcal vaccine

uncompensated

abnormal ph

1 abnormal

1 normal

fully compensated

normal ph

1 abnormal value

partially compensated

abnormal ph

2 abnormal values