How does hospital staff take care of a person in a prolonged coma?

Many things: There are many goals of care to a person in a coma. The first is to prevent complications like pneumonia, pressure sores, blood clots in the legs or arms, contractures of the joints and infections. This requires a knowledgable rehabilitation team. In addition there are medications that may hasten recovery from a coma.

Requirements vary: Coma is an altered state of consciousness that can be acute or chronic, and reversible or irreversible. The amount of supportive care required for a patient in a coma varies. Some patients require a 'respirator' with a temporary breathing tube in the trachea or a stable airway for longer term support (tracheostomy). Patients often require a feeding tube. Other means of support may also be needed.