Unconsciousness could be because of cardiac cause as well neurologically related. Cardiac causes generally considered life threatening, so get evaluated first by cardiologist and if no cause found needs neurologist evaluation in terms of CVA or Seizure may need EEG / MRI.
Next Steps
first consult cardiologist for any electrical disturbances like High degree AV Block, CHB, needs Holger monitoring, may be HUTT
Health Tips
Don't send her alone outside, night time you shoud be aware if gets up for urination, don't latch washroom