Percussion in a Case of Bronchiectasis

Percussion:

• Areas percussed: Supraclavicular, infraclavicular, mammary, inframammary, axillary, infraaxillary, suprascapular, interscapular, infrascapular (bilaterally, side-to-side comparison).

• Findings:

  • Right inframammary, infraaxillary, and infrascapular areas:

    • Impaired (dull) percussion note compared to the corresponding areas on the left side.

  • Other areas:

    • Resonant percussion note.

• Liver dullness:

  • Present at the 6th intercostal space in the right midclavicular line.

• Tidal percussion:

  • Reduced excursion on the right side.

Interpretation:
Impaired percussion note in the right lower lung fields suggests underlying consolidation, fibrosis, or collapse, which is commonly seen in bronchiectasis due to chronic infection and destruction of lung tissue.

Percussion in a Case of COPD

Percussion:

• Areas percussed:
  Supraclavicular, infraclavicular, mammary, inframammary, axillary, infraaxillary, suprascapular, interscapular, infrascapular (bilaterally, with side-to-side comparison).

• Findings:

  • All areas:

    • Percussion note: Hyperresonant in all lung fields.

    • Liver dullness: Lower border of liver dullness may be displaced downwards (liver dullness found at a lower intercostal space than normal, or may be difficult to elicit).

    • Cardiac dullness: Often obliterated or reduced.

    • Tidal percussion: May show reduced diaphragmatic excursion.

• Interpretation:
  Hyperresonant percussion note throughout the chest is characteristic of COPD due to hyperinflation of the lungs and increased air trapping. Downward displacement or obliteration of liver and cardiac dullness further supports the diagnosis of emphysematous changes in COPD.

Percussion in a Case of Pleural Effusion

Percussion:

• Areas percussed:
  Supraclavicular, infraclavicular, mammary, inframammary, axillary, infraaxillary, suprascapular, interscapular, infrascapular (bilaterally, with side-to-side comparison).

• Findings:

  • Affected side (commonly lower zones such as inframammary, infraaxillary, and infrascapular areas):

    • Percussion note: Stony dull in the areas of fluid collection.

    • Upper border of dullness: May be sharply demarcated and may show a curved line (Ellis–S-shaped line of dullness).

  • Above the level of effusion:

    • Percussion note: Impaired (dull) or sometimes a zone of shifting dullness if the effusion is free and patient position is changed.

  • Other areas (unaffected lung):

    • Percussion note: Resonant.

• Liver dullness:

  • May be difficult to distinguish from pleural dullness on the right side if the effusion is large.

• Tidal percussion:

  • Absent or markedly reduced on the affected side due to restriction of diaphragmatic movement by the effusion.

Interpretation:
A stony dull percussion note in the dependent areas of the chest, with a clear upper border, is characteristic of pleural effusion. Loss of tidal percussion and possible obliteration of liver dullness further support the diagnosis.

Percussion in a Case of Pneumonia

Percussion:

• Areas percussed:
  Supraclavicular, infraclavicular, mammary, inframammary, axillary, infraaxillary, suprascapular, interscapular, infrascapular (bilaterally, with side-to-side comparison).

• Findings:

  • Affected area (commonly one or more of the following: infraclavicular, mammary, axillary, infraaxillary, infrascapular):

    • Percussion note: Impaired (dull) note over the area of consolidation.

  • Other areas (unaffected lung):

    • Percussion note: Resonant.

• Liver dullness:

  • Present at the normal anatomical level (right 6th intercostal space in the midclavicular line).

• Tidal percussion:

  • May show reduced diaphragmatic excursion on the affected side if the lower lobe is involved.

Interpretation:
An impaired (dull) percussion note over the area of consolidation is characteristic of pneumonia. The dullness is due to alveolar filling with inflammatory exudate, replacing the normal air content of the lung.

Percussion in a Case of Lung Cavity

Percussion:

• Areas percussed:
  Supraclavicular, infraclavicular, mammary, inframammary, axillary, infraaxillary, suprascapular, interscapular, infrascapular (bilaterally, with side-to-side comparison).

• Findings:

  • Over the area of the lung cavity (commonly upper zones such as supraclavicular, infraclavicular, mammary, or suprascapular):

    • Percussion note: Hyperresonant or amphoric (hollow, high-pitched, musical quality) if the cavity is superficial, large, and has a patent bronchial communication.

    • Sometimes, a cracked-pot resonance may be elicited, especially in children or when the patient’s mouth is open during percussion.

  • Other areas:

    • Percussion note: Resonant.

• Liver dullness:

  • Present at the normal anatomical level (right 6th intercostal space in the midclavicular line).

• Tidal percussion:

  • Usually normal unless the cavity is very large and affects diaphragmatic movement.

Interpretation:
A hyperresonant or amphoric percussion note over a localized area, especially in the upper lung zones, suggests the presence of a superficial, air-filled lung cavity with bronchial communication. This is a classical finding in post-tuberculous or necrotizing lung disease with cavity formation.

Percussion in a Case of Pulmonary Fibrosis

Percussion:

• Areas percussed:
  Supraclavicular, infraclavicular, mammary, inframammary, axillary, infraaxillary, suprascapular, interscapular, infrascapular (bilaterally, with side-to-side comparison).

• Findings:

  • Affected areas (commonly lower zones such as inframammary, infraaxillary, infrascapular):

    • Percussion note: Impaired (dull) note over the fibrosed regions.

  • Other areas:

    • Percussion note: Resonant.

• Liver dullness:

  • May be at a higher level than normal on the right side if there is significant volume loss due to fibrosis.

• Tidal percussion:

  • Reduced diaphragmatic excursion on the affected side(s), reflecting restricted lung expansion.

Interpretation:
An impaired (dull) percussion note over the affected lung zones, especially in the lower fields, is characteristic of pulmonary fibrosis. This is due to replacement of normal, air-filled lung tissue with fibrous tissue, resulting in decreased resonance. Elevation of liver dullness and reduced tidal percussion further support the diagnosis of fibrosis with associated volume loss.

Viva Questions and Answers on Respiratory System Percussion

1. What is percussion in the respiratory system examination and why is it performed?
Percussion is a clinical technique where the examiner taps on the chest wall to produce sounds that help determine the underlying tissue's nature—whether it is air-filled, fluid-filled, or solid. It aids in detecting abnormalities such as consolidation, pleural effusion, or pneumothorax3.

2. Describe the correct technique for performing percussion on the chest.
Place your non-dominant middle and index fingers firmly on the patient’s chest. Using the dominant middle finger, tap quickly and sharply on the distal interphalangeal joint of the stationary finger. Percuss in a systematic manner from side to side and top to bottom, avoiding areas covered by the scapulae3.

3. What are the types of percussion notes you may encounter during a respiratory examination?

• Resonant: Normal lung tissue

• Dull: Indicates increased tissue density, such as consolidation, pleural effusion, or tumor

• Hyperresonant: Suggests increased air, as in pneumothorax or emphysema

• Stony dull: Seen in large pleural effusions35.

4. What are the causes of dullness to percussion on chest examination?

• Pleural effusion

• Consolidation (e.g., pneumonia)

• Lobectomy or pneumonectomy

• Raised hemidiaphragm

• Pleural thickening5.

5. What is the difference in percussion findings between consolidation and pleural effusion?
Both conditions are dull to percussion, but pleural effusion produces a classic “stony dullness.” Consolidation causes dullness, but not as pronounced. Additionally, in pleural effusion, vocal resonance is decreased or absent, whereas in consolidation, it is increased5.

6. What is hyperresonance on percussion and what does it indicate?
Hyperresonance is a louder, lower-pitched sound than normal resonance, indicating increased air in the lungs. It is commonly seen in conditions like pneumothorax and emphysema3.

7. What is “stony dullness” and in which condition is it found?
Stony dullness is an extremely dull percussion note with a sense of resistance, typically found in large pleural effusions5.

8. How would you use percussion to assess the position of the diaphragm?
By percussing down the posterior chest wall, the point where resonance changes to dullness marks the upper border of the diaphragm (liver dullness on the right, cardiac dullness on the left)3.

9. What are the cardinal rules of percussion in respiratory examination?

• Always percuss from areas of resonance to dullness

• Compare both sides in the same intercostal space

• Avoid percussing over bone or the scapulae

• Percuss in the intercostal spaces4.

10. How do you differentiate a transudative from an exudative pleural effusion?
By analyzing pleural fluid protein content:

• Transudate: Protein <30 g/L

• Exudate: Protein >30 g/L
  Light’s criteria are also used for differentiation5.

11. What is the clinical significance of a resonant percussion note?
A resonant note indicates normal, air-filled lung tissue3.

12. What are the percussion findings in lung collapse (atelectasis)?
Dullness to percussion is found over the area of collapse due to loss of air in the lung tissue3.

13. Why is it important to correlate percussion findings with other examination steps?
Percussion alone cannot provide a complete diagnosis; findings must be correlated with inspection, palpation, and auscultation to accurately assess and localize pathology

14. What are Light’s criteria, and how are they used to differentiate between transudative and exudative pleural effusions?

Light’s criteria are a set of biochemical parameters used to distinguish exudative from transudative pleural effusions. An effusion is classified as exudative if it meets any one of the following criteria:

• Pleural fluid protein to serum protein ratio > 0.5

• Pleural fluid lactate dehydrogenase (LDH) to serum LDH ratio > 0.6

• Pleural fluid LDH > two-thirds the upper limit of normal for serum LDH

If none of these criteria are met, the effusion is considered transudative137. Light’s criteria are highly sensitive for identifying exudates and remain the standard tool for initial evaluation of pleural effusions