A more thorough explanation:

A life-sustaining treatment is a medical procedure or treatment that is used to prolong or sustain life without curing the underlying medical condition. It is also known as a life-prolonging procedure.

Examples of life-sustaining treatments include:

• Antibiotics
• Artificial nutrition and hydration
• Ventilators
• Cardiopulmonary resuscitation (CPR)
• Dialysis

These treatments are used to keep a person alive when their body is unable to function properly on its own. For example, antibiotics may be used to treat an infection that is causing a person's body to shut down. Artificial nutrition and hydration may be used to provide a person with the nutrients and fluids they need to survive when they are unable to eat or drink on their own.

Life-sustaining treatments are often used in situations where a person's condition is not expected to improve, but they can help to keep the person alive for a longer period of time.