The letter D reminds us to look for danger that might compromise not only the injured person but the first responders as well. At no time should those people attending to any injured person put themselves at risk, and if it is not safe to approach an injured person then you should not do so.
The letter R refers to response, which is to say eliciting a response from the injured person (usually to determine whether they are conscious or unconscious and if they can tell as anything about the events leading up to the first responder finding them in need of assistance).
S reminds us to send for help early in this process, usually calling an ambulance or other people to offer assistance in anticipation that person may need to be treated before they are transported to hospital.
A is for airway and this must be clear in order to allow oxygen to enter the lungs. In the context of suspected spinal cord injury, it is necessary to think of maintaining the airway PLUS utilising cervical spine control, hence “A PLUS”.
In Basic Life Support courses, students are taught that the airway can be cleared manually by looking in the mouth and removing any obstruction, and then either moving the jaw forward or tilting the neck in order to allow free passage of air. If spinal cord injury is suspected, then it is preferable to avoid tilting the neck and utilising these or other methods for ensuring a clear airway.
However, if it is necessary to move the neck in order to make sure air can enter the lungs then this takes priority.
The B for Breathing refers to the necessity of performing expired air respiration or Bag Valve Mask resuscitation if the person is not breathing.
The letter C is in Circulation reminds the first-responder that cardiac massage may be necessary if the injured person is in cardiac arrest.