Why do you have to raise a patients head and shoulders after a head injury?

Raising a patient's head and shoulders after a head injury helps to reduce intracranial pressure by promoting venous drainage from the brain. It can also aid in maintaining an open airway and ensuring adequate blood flow to the brain. This position can be critical in assessing the severity of the injury and in preventing further complications. Additionally, it helps in monitoring for any signs of deterioration in the patient's condition.