1. Why was she bradycardic on arrival?
Bradycardia can be seen as a reponse to blood loss on it's own and is something that we have seen in penetrating trauma over the years. It is less common as a response in blunt trauma. It may also be a preterminal rhythmn which is entirely possible with this degree of injury. However, in this case the bradycardia is certainly a function of the spinal injury owing to the disruption of sympathetic outflow from the thoracic spine.

2. How can someone recover so rapidly from such a profound metabolic derangment?
Damn good resuscitation :-) , maybe, but also because this was a very acute injury that had a very rapid and retrievable treatment in fluids and vasopressors. Once the spinal component of the injury became apparent we used ephedrine and then nor-adrenaline to maintain peripheral tone.

3. What is the prognosis for recovery?
Not good from the spinal point of view. However, from the brain perspective the patient is fully intact. In our experience this is the most profound degree of metabolic derangement in trauma, with survival, that we have seen.