Gas, laughing

Nitrous oxide, a gas capable of causing general anesthesia. Today nitrous oxide is sometimes given in the company of other anesthetic agents but is no longer used as the sole anesthetic agent because the concentration of nitrous oxide needed to produce anesthesia is close to the concentration that seriously lowers the blood oxygen level and creates a hazardous state of hypoxia. Nitrous oxide figures prominently in the early history of anesthesiology. In 1840 a dentist named Horace Wells thought that, using the recently discovered "exhilarating or laughing gas," teeth might be pulled without pain. Under its influence he had one of his own teeth pulled in 1844 and afterward often employed nitrous oxide in his practice. Dr. Wells gave a demonstration with a patient at the Massachusetts General Hospital. Things did not go too well there. The patient suffered great pain. Dr. Wells became depressed, became addicted (to chloroform, another anesthetic agent) and in 1848 committed suicide.