Disorders of Consciousness: Brain Death, Coma, and the Vegetative and Minimally Conscious States -

You need to be extremely concerned about this. There was not enough discussion of locked-in syndrome so it is unlikely your doctor will know what to do in that case. Or the common misdiagnosis of stroke as drunkeness or balance issues.
http://www.dana.org/Publications/ReportOnProgress/Disorders_of_Consciousness__Brain_Death,_Coma,_and_the_Vegetative_and_Minimally_Conscious_States/