What can happen unconscious casualty left on their back?

An unconscious casualty left on their back is at risk of several complications, including:

1. Airway Obstruction: The tongue and soft tissues of the mouth can relax and block the airway, making it difficult or impossible for the person to breathe. This can lead to oxygen deprivation and severe brain damage or even death.

2. Aspiration: If the person vomits while lying on their back, there is a risk of aspiration, where the vomit can enter the lungs. This can cause pneumonia and other respiratory complications.

3. Poor Circulation: Lying on the back can impede blood circulation, especially to the brain. This can result in inadequate oxygen supply to the brain and potential brain damage.

4. Muscle Damage: Prolonged lying on a hard surface can put pressure on the muscles and nerves, leading to discomfort and potential damage.

5. Pressure Sores: Unconscious individuals may not be able to reposition themselves, which can increase the risk of developing pressure sores, especially on pressure points like the heels, elbows, and buttocks.

6. Delayed Recovery: Maintaining a stable side position helps promote better circulation, respiration, and overall recovery compared to lying on the back.

Therefore, it's crucial to properly position an unconscious casualty in the recovery position (on their side) to prevent these complications and ensure their safety until medical assistance arrives.