Hemodynamic effects of decompressive craniectomy in cold induced brain oedema.

An experimental model of cold induced brain oedema was carried out in 7 albino rabbits by topic application of fluid N2 on the skull to examine the favourable effects of an appropriate tailored craniodural opening both on the whole brain perfusion and on the local dynamics of the oedematous fluid. After positioning the animals in a stereotactic frame the following parameters were recorded: ICP, carotid blood pressure and flow velocity, EEG, EKG. Histological staining with Evan's blue was utilized to check fluid extravasation. In all the animals the lesion was followed both by an ICP increase and a reduction in the carotid blood flow velocity so indicating an increase in the cerebrovascular resistances. In 4 animals the removal of the craniodural flap over the lesion dramatically reduced the ICP values and normalized the blood flow velocity. No difference in the Evan's blue distribution was noticed between the two groups of animals.