Decompression sickness (DCS), sometimes called Caisson disease, is caused by bubbles of nitrogen gas in the blood and tissues after a rapid decline in the ambient barometric pressures occurs. This is usually seen when divers ascend too rapidly from a deep dive. Symptoms include pain, skin rash, fatigue, headache, vertigo, and confusion. In severe cases, it can lead to death. Prevention is through correct dive procedures and the use of dive tables or computers to limit ascent rates.