Key Concepts
Introduction
Pneumothorax results from disruption of the visceral or parietal pleura, allowing air to accumulate in the normally negative-pressure pleural space. In a simple pneumothorax, the lung collapses proportional to the volume of trapped air. In a tension pneumothorax, a one-way valve mechanism allows air entry but prevents exit, causing progressive ipsilateral lung collapse and mediastinal shift. This shift compresses the contralateral lung and impedes venous return to the heart, leading to obstructive shock. The nurse must perform rapid respiratory and cardiovascular assessment, assist with or prepare for needle decompression or chest tube insertion, manage the chest drainage system, and monitor for complications including re-expansion pulmonary edema. On the exam, writers often pair stable-sounding options with unstable dataโnotice the mismatch before you commit. If the stem names a license or role, reread that line; scope errors are classic trap answers even when the clinical topic is familiar. Run a 60-second scan: breathing work and oxygenation, perfusion and end organs, neuro baseline, likely infection sources, and devices that can fail quietly. When two answers feel partly right, pick the one that **reduces...