31-year-old Langfield is described as being 'stable', and is currently recovering in Glasgow's Southern General Hospital.
AFC Chief Executive Duncan Fraser told the official Aberdeen website RedWeb: "Obviously this is an extremely worrying time for Jamie and the thoughts of everyone at the Club are with him, Louise and the girls.
"Jamie had a comfortable night and there have been no further setbacks but, until the results of the tests he has undergone are known, we are not in a position to comment further."