The influence of the decompressive operation on the intracranial pressure and the pressure-volume relation in patients with severe head injuries.

Measurements of intracranial pressure by ventricular catheter were performed in 47 patients with severe head injuries. Thirty-three patients with decompressive operations such as osteoclastic craniotomy and dilatation by means of duraplastic have been compared with 14 patients with closed heads with regard to volume pressure response (intracranial elasticity). This was determined either by intraventricular injection of 2ml saline or by drainage of cerebrospinal fluid. The examination clearly shows that patients with closed heads have a much higher intracranial elasticity than patients who have decompressive operations, so that in the first group minor differences of the intracranial volume cause extreme deviations of the intracranial pressure. Therefore, the decompressive operation has been advised in severe head injuries with increased intracranial pressure as a measure additional to high dose dexamethasone therapy and hyperventilation.