Which medical gas is most commonly used for anesthesia?

Nitrous oxide is the medical gas most commonly used for anesthesia due to its unique properties that make it ideal for inducing and maintaining anesthesia in patients. It is a colorless and odorless gas that provides analgesic effects, which means it can help relieve pain while also producing a state of sedation.

One of the key benefits of nitrous oxide is its rapid onset and offset of action, allowing for quick adjustments during procedures. This is particularly useful in various medical and dental settings where immediate effects are required. Additionally, nitrous oxide can be mixed with other anesthetic agents to enhance their effectiveness, making it versatile in practice.

In contrast, while oxygen is essential for patient breathing and maintaining adequate oxygenation, it does not provide the analgesic and anesthetic properties necessary to perform surgical procedures. Carbon dioxide is used primarily in specific medical situations, such as insufflation during laparoscopic surgeries, but it is not an anesthetic. Helium is not utilized in anesthesia; rather, it may be used for therapeutic purposes in certain respiratory treatments due to its low density and ability to improve airflow.