**Question:** Decompression sickness is seen in which of the following individuals?

A. Divers
B. Pilots
C. Mountaineers
D. Long distance drivers

**Core Concept:** Decompression sickness (DCS) is a potentially life-threatening complication that can occur when there is a rapid change in pressure, especially when a diver ascends too quickly from a deep depth to the surface without following the recommended decompression procedures. DCS is caused by the formation and migration of gas bubbles in the bloodstream and tissues due to the pressure differential. This can lead to neurological, pulmonary, or joint symptoms.

**Why the Correct Answer is Right:** Divers are at a higher risk of developing decompression sickness due to the rapid changes in pressure when they ascend from deep water to the surface without following decompression protocols. These protocols are designed to allow gas to dissolve in the body and be exhaled gradually to prevent excessive gas bubbles formation and subsequent complications.

**Why Each Wrong Option is Incorrect:**

- Pilots are not directly related to the risk of decompression sickness. While altitude changes in aviation might lead to altitude sickness (e.g., high-altitude pulmonary edema), these conditions are not directly comparable to decompression sickness due to pressure differences.
- Mountaineers are exposed to altitude changes, but the pressure difference is not as significant as in diving, making decompression sickness less likely.
- Long-distance drivers are not directly associated with decompression sickness due to their occupation. The risk factors for decompression sickness are primarily related to the pressure changes experienced by divers and not surface occupations.

**Clinical Pearl:** Divers should follow decompression procedures carefully to avoid decompression sickness. When planning ascents, divers should calculate the necessary decompression stops based on depth and duration of their dive to minimize the risk of decompression sickness. In case of a dive emergency, ascend to a safer depth and consult a medical professional for further management.

**Correct Answer:** Divers (Option A) are at the highest risk for decompression sickness due to the pressure changes involved in diving and the risk of gas bubble formation.