Diving related illnesses can be divided into two categories: conditions caused by changes in ambient pressure during dives and conditions caused by the general diving environment. Conditions caused by pressure changes include barotraumas from pressure changes during descent and ascent like ear injuries and decompression sickness from nitrogen bubbles in the blood after rising to the surface. Treatment may include 100% oxygen initially, hyperbaric oxygen therapy, IV fluids, and recompression therapy in a hyperbaric chamber.