The purpose of chest percussion and vibration is to loosen secretions in the lungs. The difference between the procedures is:
Correct Answer: D
Rationale: Chest percussion involves the use of rhythmic tapping to dislodge mucus from the lungs, facilitating its movement toward the larger airways where it can be expelled. This technique is particularly important in conditions where mucus retention is a significant risk factor for infection. The key difference between chest percussion and vibration is that percussion involves slapping the chest to loosen secretions, while vibration involves shaking the secretions along with the inhalation, aiding in moving the loosened secretions upwards for easier removal. Choices A, B, and C do not accurately describe the main difference between chest percussion and vibration, making them incorrect.