Which of the following is a common type of medical gas?

Oxygen is one of the most common types of medical gas used in healthcare settings. It plays a crucial role in patient care, particularly in situations where individuals are unable to obtain adequate oxygen through normal respiration. Oxygen therapy is commonly employed for patients with respiratory issues, during surgical procedures, and for those requiring increased oxygen levels for healing and recovery.

It is essential in various medical environments such as hospitals, ambulatory surgery centers, and emergency response. The therapeutic effects of oxygen are well-documented, and its use is standardized in many treatment protocols, highlighting its vital importance in medical practice.

The other gases mentioned, while they have specific uses, do not match the broad significance of oxygen in patient care. For example, ammonia is not used for therapeutic purposes due to its toxicity, helium has specialized applications often related to diagnostics or procedures, and carbon dioxide is primarily utilized in certain medical procedures like insufflation during surgeries but does not serve as a primary life-sustaining gas.