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Difficulty: MediumPhysical Examination Findings

A 68-year-old man with a 45-pack-year smoking history is evaluated in the hospital for worsening shortness of breath and a persistent, dry cough over the past three weeks. He reports an unintentional weight loss of 4 kg (8.8 lb) over the last month. His temperature is 37.2°C (99.0°F), blood pressure is 138/82 mmHg, pulse is 94/min, and respiratory rate is 22/min. Pulse oximetry shows 92% on room air. On physical examination of the chest, inspection reveals asymmetric chest expansion with decreased movement on the right side. Palpation demonstrates a trachea that is distinctly deviated to the right, along with markedly decreased tactile fremitus over the right anterior and posterior hemithorax. Percussion is uniformly dull over the right lung fields. Auscultation reveals absent breath sounds on the right side. Cardiac examination is unremarkable. Which of the following is the most likely diagnosis based on these physical examination findings?

  1. Complete endobronchial obstruction of the right mainstem bronchusAnswer
  2. B
    Large right-sided malignant pleural effusion
  3. C
    Right-sided lobar consolidation
  4. D
    Right-sided tension pneumothorax
  5. E
    Advanced idiopathic pulmonary fibrosis

Answer

Complete endobronchial obstruction of the right mainstem bronchus
The correct answer accurately synthesizes the four key physical examination findings of massive atelectasis caused by a complete mainstem bronchus obstruction. Endobronchial obstruction (commonly due to bronchogenic carcinoma in a heavy smoker) causes resorption of air distal to the occlusion, leading to lung collapse (atelectasis). This massive volume loss pulls the mediastinum and trachea TOWARD the side of the lesion (ipsilateral deviation). The collapsed, airless lung yields dullness to percussion. Because there is no airflow into the collapsed lung and the airway is entirely obstructed, breath sounds are absent and tactile fremitus is decreased.

Step-by-Step Solution

1
Analyze the percussion and breath sound findings.
The right hemithorax exhibits dullness to percussion and absent breath sounds.
Normal air-filled lung is resonant; replacement by fluid or a collapsed airless lung causes dullness. Absent breath sounds indicate a lack of airflow reaching that region.
2
Evaluate the tactile fremitus.
Tactile fremitus is markedly decreased on the right.
Consolidation with a patent airway increases sound transmission (increased fremitus), whereas an obstructed airway or intervening pleural fluid decreases sound transmission.
3
Assess the position of the trachea.
The trachea is deviated to the right (the ipsilateral side).
Ipsilateral tracheal deviation signifies massive volume loss (atelectasis) pulling the mediastinum. Conversely, a large effusion or tension pneumothorax adds volume and pushes the mediastinum to the contralateral side.
4
Synthesize the physical examination findings into a single diagnosis.
The combination of ipsilateral tracheal deviation, dullness to percussion, decreased fremitus, and absent breath sounds points to complete endobronchial obstruction.
An obstruction (such as a bronchogenic carcinoma) prevents airflow, causing distal air to be resorbed. The lung collapses, resulting in significant volume loss that pulls the trachea toward the affected lung.

Key Concept

Differentiation of pulmonary pathology using the diagnostic constellation of percussion note, breath sounds, tactile fremitus, and tracheal deviation.
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Topics

Physical Examination Findings

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