Function

• Humans are exposed to small amounts of carbon dioxide on a daily basis, as it is present in the air in small concentrations. It is also present in human blood at a very low level, and helps to auto regulate the body's blood supplies by signaling the capillaries to expand as a means of increasing blood flow.
  
  

How it Occurs

• Carbon dioxide poisoning can occur in a number of ways. Hypoventilation, or decreased rate of breathing can lead to a dangerous buildup of levels of carbon dioxide. People who are exposed to very high altitude conditions with low oxygen levels are also subject to this problem. Rebreathing exhaled carbon dioxide or exposure to high environmental levels can also result in poisoning.
  
  

Warning

• Carbon dioxide poisoning, or hypercapnia, is extremely dangerous. High blood levels of the compound reduce the body's ability to take in oxygen and to adequately supply the organs. Prolonged exposure to poisonous levels of carbon dioxide can be fatal. Treatment for hypercapnia includes exposure to high levels of oxygen and rest. If the victim is unresponsive, 911 should be called.
  
  

Effects

• Carbon dioxide poisoning deprives the body's tissues of oxygen, resulting in what amounts to suffocation. Symptoms of poisoning include muscle twitches and flushed skin progressing to panic and hyperventilation as the victim frantically attempts to breathe in more oxygen. Left untreated, it will progress to convulsions, unconsciousness and, ultimately, death.
  
  

Prevention

• Most cases of carbon dioxide poisoning from an environmental source occur in scuba divers. Divers should be carefully trained as to the causes and symptoms of poisoning, and should always dive with others who are also trained and can offer assistance if needed. Causes of incidents of poisoning in scuba divers can be attributed to improper care of breathing equipment, wetsuits that are too tight, regulator malfunction and inadequate breathing.