Soon after central-line placement, a client develops sudden dyspnea, falling oxygen saturation and newly asymmetric breath sounds. Click the region in this schematic that best accounts for loss of normal lung expansion.

D. D lies outside the contracted right lung but inside its chest-wall pleural boundary.

The depicted air collection separates the visceral and parietal surfaces, allowing the lung to recoil. This location, combined with the acute post-procedure respiratory change, supports urgent evaluation for pneumothorax. The diagram is not a diagnostic radiograph and does not establish tension physiology.

The observations are fictional teaching data. Apply the stated context; the selected feature does not by itself replace a complete bedside assessment.

Air location matters: within the airway or lung differs from air in the pleural space.

Air location matters: within the airway or lung differs from air in the pleural space.

A is the central airway, where air is normally present. B is the opposite lung tissue. C is central mediastinal tissue. D identifies the new abnormal compartment rather than simply a normally air-containing structure.

• Pleural air separates the lung from the chest wall — Air location matters: within the airway or lung differs from air in the pleural space.
• Comparison with context — A also contains air, but its normal anatomical compartment does not explain the new loss of expansion.