What is the best method of open airway an unresponsive victim when you can not suspect cervical spine injury?

Chin Lift with Jaw Thrust - This technique is used when you can't suspect cervical spine injury:

1. Place one hand on victim's forehead and pinch the nose shut with the other hand.

2. Gently, with fingers underneath the chin but without pressing backward on soft tissues around neck, lift chin sufficiently to raise victim's head until airway opens.

3. If no resistance is encountered, you may need to thrust the victim's jaw forward (in addition to the chin lift) to open the airway.