Likewise the solubility of these gases doubles. If our diver goes down another 32 feet the partial pressures are 2.4 atm and 0,6 atm, respectively, tripling the solubility of the air in the blood. Since the diver is usually swimming and physically active, there is little or no effect of the increased oxygen at these depths. However, if our diver were to come to the surface quickly after having come to equilibrium at 64 feet, the rapid decrease in pressure would cause the nitrogen dissolved in the blood to come out of solution like a soda when its top is opened. Although the gas bubbles aren't very large, they are more than sufficient to block the tiny capillaries throughout the body, cause considerable pain, and even death if blood flow through the brain is affected.
Large bubbles can actually tear the walls of blood vessels causing considerable damage.
Diving training usually includes rigid protocols for wait times while ascending from any significant depths to allow the nitrogen and oxygen time to reequilibrate in the blood. At elevated pressures nitrogen is known to cause drowsiness and stupor, therefore, professional divers working at great depths will breathe gas mixtures that keep the partial pressure of oxygen near normal levels while replacing the nitrogen with a relatively insoluble gas such as helium.