1980 Volume 20 Issue 1 Pages 53-60
Fourteen cases of surgically treated acute subdural hematomas were studied. The indication of external decompressive hemicraniectomy for these cases of acute subdural hematomas was studied in detail according to postoperative intracranial pressure (pICP) changes in combination with their preoperative neurological, cardiorespiratory and angiographic findings.
The pICP changes were classified into three groups according to the maximum values of intracranial pressures and the patterns of the pressure changes.
Group one: pICP increased rapidly and progressively immediately after the operation, and then it reached the level of mean arterial blood pressure. This rapid increase of pICP in this group seemed to be the result of cerebral vasomotor paralysis. There was no effective treatment for these cases.
Group two: pICP remained in the range of 40 to 70mmHg. Preoperative neurological examinations of these cases showed semicoma or coma not having the signs of brain stem dysfunction. Preoperative angiograms revealed the delay of circulation time and fairly good filling of small arteries in an early arterial phase. Operative findings in these cases showed that extensive cerebral contusion affected more than two lobes without any definitive brain swelling. Postoperative intracranial pressure might have continued to increase as shown in Group one, if external decompressive hemicraniectomy had not been performed for these cases. It was considered that external decompressive hemicraniectomy should be restricted to this group.
Group three: pICP remained 10 to 30mmHg. Indication of external decompressive hemicraniectomy was not suggested for cases in this group.
