AEMCA Practice Exam

What effect does decompression have on nitrogen levels in the body?

1. Nitrogen bubbles dissolve

2. Nitrogen bubbles expand

3. Nitrogen is expelled rapidly

4. Nitrogen levels remain constant

The correct answer is: Nitrogen bubbles expand

During decompression, the effect on nitrogen levels in the body is primarily that nitrogen bubbles expand. This phenomenon occurs because, during periods of increased pressure, such as when divers are underwater, nitrogen from the air we breathe gets absorbed into the body's tissues. When a diver ascends and experiences decompression, the pressure around them decreases, causing the dissolved nitrogen in the body to form bubbles. As the pressure drops, these bubbles expand due to the reduced external pressure. This expansion can lead to various complications, commonly referred to as decompression sickness or "the bends." It is crucial for divers to ascend slowly and perform safety stops to allow the nitrogen to safely re-dissolve into the bloodstream and be expelled through the lungs, rather than forming large bubbles that can block blood vessels and cause injury. Other options do not accurately describe the process; for instance, the dissolving of nitrogen bubbles (as mentioned in one option) does not occur rapidly during the decompression phase, and nitrogen levels do not remain constant, nor is it expelled rapidly in a controlled manner.