Which of the following casualties may benefit from supplemental oxygen?

Supplemental oxygen can significantly improve outcomes for casualties who have impaired oxygenation. This means they are not effectively absorbing or utilizing oxygen in their bloodstream, commonly due to conditions like respiratory issues, trauma, or other medical emergencies that can compromise breathing and gas exchange. Providing supplemental oxygen directly addresses this problem, enhancing tissue oxygenation and potentially preventing further complications such as hypoxia.

In contrast, while providing oxygen to casualties at ground level, conscious casualties, or those without injuries might seem beneficial, it doesn't specifically target a critical need. Casualties at ground level may not necessarily have any impairment that would warrant supplemental oxygen, conscious casualties may be stable without it, and those without injuries most likely do not require oxygen therapy at all. Thus, the focus remains on those who are experiencing inadequate oxygenation, making supplemental oxygen vital for their treatment.