In the DOPE mnemonic for ventilation troubleshooting, which category indicates displacement of the tube from its proper position?

• A. Displacement
• B. Obstruction
• C. Pneumothorax
• D. Equipment

Answer: (A)

The DOPE framework is a quick way to categorize ventilation problems into Displacement, Obstruction, Pneumothorax, and Equipment issues. The category that indicates the tube has moved from its proper position is Displacement—meaning the endotracheal tube has shifted in or out of the trachea (for example, advanced into a mainstem bronchus or pulled out of the trachea). This distinction matters because it directly explains why ventilation fails despite the equipment being intact and the airway not obstructed or damaged.

When displacement occurs, you’ll typically see signs like poor or absent breath sounds, asymmetric chest movement, possible gastric distension, and sometimes a misleading capnography waveform. The fix is to quickly recheck the tube’s position with direct visualization or laryngoscopy, adjust the depth so the tip sits about 2–3 cm above the carina, then re-secure the tube and confirm proper placement with bilateral breath sounds and capnography, aided by imaging if available.