Relations of intracranial pressure, creatine kinase and brainstem auditory evoked potential in patients with traumatic brain edema.

We studied the relations of intracranial pressure (ICP), creatine kinase (CK) and brainstem auditory evoked potential (BAEP) in 44 patients with traumatic brain edema who were admitted to our hospital from June 1990 to February 1991. There were 30 males and 14 females, with age range from 9 to 67 years. The results showed that the abnormal BAEP could reflect the severity of cerebral edema in acute head injury and was related to ICP and serum CK levels. When ICP > 30 mmHg (4kPa), the abnormality of BAEP was more obvious than that of the control group (P < 0.05); the serum CK levels were also elevated markedly. In patients with ICP over and below 4kPa, the rate of abnormal BAEP was 38.46% and 77.78% respectively (P < 0.05). The serum CK level in the normal group or in the group with moderate abnormality of BAEP was significantly different from that in the group with severe abnormality or lack of BAEP (274.8 +/- 98.24 U/L vs 705.3 +/- 364.27 U/L; P < 0.001). After treatment, the ICP returned to normal, and the BAEP normalized too, but the serum CK level decreased. The results showed that BAEP may provide some indirect evidences for the relevant biochemical and biophysical changes after the occurrence of traumatic brain edema and an important clinical index for judging the severity of the edema.