Characteristic oscillations of intracranial pressure after delayed lowering of blood pressure in patient with shearing injury.

A comatose patient with severe shearing injury showed hyperthermia, leucocytosis and decerebration. Rapid disappearance of brain swelling as well as a transient fall of blood pressure were peculiar in his clinical course. Large pressure waves appeared more frequently after such attacks. The authors concluded that cerebral vasomotor instability was caused by a primary lesion throughout an area from the anterior hypothalamus to the upper brain stem. Pre-existing hypoxia in such primary lesions was augmented by hypotensive episodes. Frequent appearance of large pressure waves was thought to represent progressive vascular engorgement followed by an uncontrollable increase of the ICP.