Final answer:
Performing chest compressions is the method used to clear a severe airway obstruction in an unconscious adult patient.
Step-by-step explanation:
The method of clearing a severe airway obstruction in an unconscious adult patient is to perform chest compressions. When a person is unconscious and unable to clear their airway themselves, chest compressions are used to push air out of the lungs and help dislodge any obstructions in the airway. It is important to call for emergency medical care immediately if the obstruction cannot be cleared by chest compressions alone.