Clinical and electroencephalographic evolution of the sequelae of anoxic-ischemic encephalopathy. Case report

Abstract

Brain damage is the main cause of disability worldwide. Diverse procedures have been focused

for quantitative assessment of central nervous system improvement but an absolute agree-
ment has been not achieved. Follow-up by quantitative electroencephalogram was a reliable

resource in present case. A woman aged 43, sustained postpartum uterine massive bleeding
that required hysterectomy in december 2010, evolving into hypovolemic shock and a shallow
comma as well as cardiac arrest. Patient survived after reanimation maneuvers at an Intensive

Care Unit. She was admitted into our institution by early 2011 where a neurological rehabilita-
tion program was given. A critical condition was present since only brain stem reflexes were

present. Serial electroencephalogram and neuroimaging tests revealed patient’s evolution from

an initial sluggish recording and a reduced spectral power density indicating severe cortico-
cortical damage, into a progressive improvement in δ, Θ, α and β waves. Gradual activation

of α and β (synchronization/disinchronization) was observed, with a predominance of right
hemisphere. Those changes were congruent to the observed clinical improvement in motor
and sensory reflexes as well as low conscious capacity. The spectral power density kept onimprovement with reduction in relative power of Θ, less of δ but with an increase in α and β.
That indicates a partial recovery of reticular-thalamic-cortical circuits, which were responsible
of a minimal awaking condition. In conclusion, relevance of brain the spectral power density
serial evaluation by quantitative electroencephalogram must be remarked, altogether with
clinical examination. Main prognostic predictor is the a activity.