Which gas is commonly mixed with nitrous oxide for its analgesic effects?

Oxygen is commonly mixed with nitrous oxide because it enhances the safety and effectiveness of the sedation provided by nitrous oxide. When nitrous oxide is used for analgesia and sedation, the addition of oxygen helps to maintain adequate oxygenation for the patient. This is important because while nitrous oxide is a safe anesthetic agent, it can displace oxygen in the lungs if used in high concentrations.

The combination of nitrous oxide and oxygen not only helps prevent hypoxia but also reduces the potential side effects associated with nitrous oxide use, such as dizziness or disorientation. The typical mixture administered in medical settings is around 30% nitrous oxide to 70% oxygen, ensuring that the patient remains aware and safe during procedures while still receiving the analgesic benefits of the nitrous oxide.

In contrast, the other gases mentioned—nitrogen, carbon dioxide, and helium—do not provide the same protective effects and may either not contribute to analgesia or could introduce risks if used in conjunction with nitrous oxide in a clinical setting.