Overview
This lecture covers the four-step chest assessment process for respiratory therapists, highlighting techniques to detect and interpret physical and auditory signs of lung disease.
Steps of Chest Assessment
- Chest assessment includes inspection, palpation, percussion, and auscultation.
- Mastering these steps helps identify early changes in patients’ respiratory status and underlying disease.
Types of Lung Diseases
- Obstructive diseases (e.g., COPD, asthma, emphysema) cause difficulty exhaling due to narrowed airways.
- Restrictive diseases (e.g., neuromuscular disorders, pulmonary fibrosis) limit air intake due to stiff or weak lungs.
- Ventilation-perfusion (VQ) mismatch occurs when air flow doesn't match blood flow, as seen in pleural effusion or pneumothorax.
Chest Wall Abnormalities
- Barrel chest: expanded rib cage, common in obstructive lung disease.
- Pectus carinatum (pigeon chest): sternum protrudes outward.
- Pectus excavatum (funnel chest): sternum is sunken inward, more common than carinatum.
- Kyphosis: abnormal anterior-posterior spinal curvature.
- Scoliosis: lateral spinal curvature.
- Kyphoscoliosis: combination of kyphosis and scoliosis.
- Treatment for pectus carinatum involves braces; pectus excavatum may use vacuum bell or surgical correction.
Thoracic Expansion and Palpation
- Assess chest expansion by placing hands on the back near T8 and observing thumb movement as patient breathes deeply.
- Unequal or reduced expansion suggests underlying lung pathology.
- Palpation checks for tactile fremitus (vibration while speaking): increased in consolidation (pneumonia), decreased in air/blockage (emphysema, pneumothorax).
- Crepitus under skin signals subcutaneous emphysema.
Percussion Technique
- Percussion is tapping on the chest to assess underlying tissue.
- Normal lung sounds resonant; dullness suggests fluid/consolidation, hyper-resonance indicates excess air (emphysema, pneumothorax).
- Compare both sides systematically.
Auscultation and Breath Sounds
- Use the diaphragm of the stethoscope to listen for breath sounds.
- Normal breath sounds: tracheal (loudest), bronchovesicular (over sternum), vesicular (soft, over lung tissue).
- Abnormal (adventitious) sounds:
- Crackles (fine/coarse): indicate fluid or small airways opening.
- Wheezes: musical, continuous, suggest narrowed airways.
- Stridor: harsh, high-pitched, indicates upper airway obstruction.
- Pleural friction rub: creaking sound from inflamed surfaces.
Interpreting Changes in Breath Sounds
- Diminished or absent breath sounds may indicate pleural effusion or pneumothorax.
- Bronchial breath sounds in the periphery signal lung consolidation (pneumonia).
- Tactile fremitus and percussion findings help distinguish causes.
Stethoscope Use and Infection Control
- Stethoscope parts: bell, diaphragm, tubing, earpieces.
- Diaphragm is best for lung sounds; bell for lower frequency heart sounds.
- Always clean the stethoscope after each use to prevent infection.
Key Terms & Definitions
- Palpation — using hands to feel the chest wall’s movement and vibrations.
- Percussion — tapping on the chest to assess underlying lung tissue.
- Auscultation — listening to breath sounds with a stethoscope.
- Tactile fremitus — palpable vibration from patient’s voice.
- Resonance — characteristic percussion note of normal, air-filled lung.
- Crackles — abnormal, discontinuous lung sounds.
- Wheezes — high-pitched, continuous abnormal lung sounds.
- Stridor — harsh, high-pitched inspiratory sound from upper airway obstruction.
Action Items / Next Steps
- Watch the recommended videos on percussion, auscultation, and tactile fremitus techniques.
- Practice chest expansion, palpation, and auscultation skills in the upcoming lab session.
- Review and study the characteristics of normal and abnormal breath sounds.