Posterior Chest/Thoracic Cage Examination

Inspect the Posterior Chest/Thoracic Cage

• Spinous processes should appear in a straight line.
• The thorax should be symmetric and elliptical with downward sloping ribs at about 45 degrees relative to the spine.
• Scapulae are placed symmetrically in each hemithorax.
• The anteroposterior (AP) diameter should be less than the transverse diameter, with a ratio of about 0.70 to 0.75 in adults, increasing with age.
• Skeletal deformities like scoliosis and kyphosis may limit thoracic cage excursion.
• An AP to transverse diameter ratio of 1:1 occurs in "barrel chest", where ribs are horizontal, often seen in COPD due to hyperinflation.
• Neck and trapezius muscles should be developed normally for age and occupation
• Neck muscles are hypertrophied in COPD due to aiding in forced respirations across the ostructed airways
• The person should have a relaxed posture, supporting their weight comfortably.
• People with COPD often sit in a tripod position, leaning forward with arms braced.
• Skin color should be consistent with genetic background, with allowance for sun-exposed areas.
• No cyanosis or pallor should be present.
• Cyanosis indicates tissue hypoxia.

Symmetric Expansion

• Place warmed hands sideways on the posterolateral chest wall with thumbs pointing together at T9 or T10 level.
• Slide hands medially to pinch up a small fold of skin between thumbs to confirm symmetric chest expansion.
• Unequal chest expansion occurs with marked atelectasis, lobar pneumonia, pleural effusion, thoracic trauma (fractured ribs), or pneumothorax.
• Pain accompanies deep breathing when the pleurae are inflamed.

Tactile Fremitus

• Fremitus is a palpable vibration.
• Assess tactile (or vocal) fremitus, where sounds from the larynx are transmitted through bronchi and lung parenchyma to the chest wall.
• Use the palmar base of the fingers or ulnar edge of one hand, touching the person's chest as they repeat "ninety-nine" or "blue moon".
• Start palpating over the lung apices from one side to the other for resonant phrases.
• Symmetry is most important, vibrations should feel the same on each side.
• Fremitus is most prominent between the scapulae and around the sternum, where major bronchi are closest to the chest wall.
• Fremitus normally decreases as you progress down the chest.
• Fremitus feels greater over a thin chest wall, and less over an obese or heavily muscular one.
• A loud, low-pitched voice generates more fremitus than a soft, high-pitched one.
• Asymmetric findings suggest dysfunction.
• Decreased fremitus occurs with obstructed bronchus, pleural effusion or thickening, pneumothorax, or emphysema.
• Increased fremitus occurs with compression or consolidation of lung tissue (e.g., lobar pneumonia), when the bronchus is patent and the consolidation extends to the lung surface.
• Rhonchal fremitus is palpable with thick bronchial secretions.
• Pleural friction fremitus is palpable with inflammation of the pleura.
• Crepitus is a coarse, crackling sensation palpable over the skin, which occurs in subcutaneous emphysema when air escapes from the lung.

Percuss the Posterior Chest/Lung Fields

• Determine the predominant note over the lung fields, start at the apices, and percuss the band of resonant tissue across the tops of both shoulders.
• Percuss in the interspaces making a side-to-side comparison, at 5 cm intervals, avoiding the scapulae and ribs.
• Resonance is the low-pitched, clear, hollow sound predominating in healthy lung tissue in the adult.
• Resonance is relative and has no constant standard.
• Asymmetry is important where one side with prominent dullness or marked hyperresonance indicates underlying disease.
• Percussion has limits penetrating only the outer 5 to 7 cm of tissue.
• An abnormal finding must be 2 to 3 cm wide to yield an abnormal percussion note.
• Hyperresonance is a lower-pitched, booming sound when too much air is present such as in emphysema or pneumothorax.
• A dull note (soft, muffled thud) signals abnormal density in the lungs, as with pneumonia, pleural effusion, atelectasis, or tumor.

Auscultate the Posterior Chest

• The passage of air through the tracheobronchial tree creates sounds audible through the chest wall.
• Breath sounds are changed by obstruction in the passageways or by disease in the lung parenchyma, the pleura, or the chest wall.

Breath Sounds

• Evaluate the presence and quality of normal breath sounds.
• The person should be sitting, leaning forward slightly, arms resting comfortably.
• Instruct the person to breathe through the mouth, a bit deeper than usual, stopping if they feel dizzy.
• Monitor breathing throughout the examination and offer rest periods.
• Clean the flat diaphragm endpiece of the stethoscope and hold it firmly on the person's chest wall, listening to at least one full respiration in each location.
• Side-to-side comparison is most important.
• Do not confuse background noise with lung sounds, such as: examiner's breathing on stethoscope tubing or stethoscope tubing bumping together.