ABSTRACT
BACKGROUND: Applying naloxone in acute brain injury can sustain the cerebral perfusion pressure(CPP), alleviate the cerebral edema and prevent the secondary brain damage to a certain degree. But the dosage and the administration of naloxone in clinical practices vary substantially according to the literatures.OBJECTIVE: To investigate the effect of different doses of naloxone on the changes in the absolute power values of electroencephalography(EEG) in acute brain injury, and study the protective effects of naloxone at different doses.DESIGN: Case-control study based on patients.SETTING: Neurosugery department of a hospital affiliated to a university PARTICIPANTS: From January 2002 to April 2003, at the Intensive Care Unit(ICU) of theNeurosugery Department of the First Hospital Affiliated to the Chongqin Medical University, 86 patients with moderate or severe acute closed brain injury were selected. Of all the patients, 59 were male and 27 were female, aged between 18 - 65.METHODS: According to the degree of injury graded by Glasgow Coma Scale(GCS), the 86 patients bearing acute brain injury were divided into 3 groups: GCS 3 - 5 group, GCS 6 - 8 group and GCS 9 - 12 group. Each group contained a naloxone treatment group and a matched control group. The naloxone treatment group consisted of a low-dose naloxone subgroup and a large-dose naloxone subgroup. The changes in the total power value of EEG before treatment and at the time of 30 minutes, 1, 2, 24, 48, 72 and 120 hours after treatment were measured respectively using quantitative EEG monitor.MAIN OUTCOME MEASURES: The changes in the total power value of the patients' EEG before and after treatment were observed and recorded.RESULTS: The difference between the total power of EEG of the GCS 9 - 12naloxone treatment group 1 hour after a naloxone treatment and that of the matched control group was statistically significant(P ＜ 0.05); The same comparison between the low-dose and the large-dose naloxone subgroups within the GCS 9 - 12 naloxone treatment group yielded no significant difference. In the GCS 6 - 8 naloxone treatment group, the difference between the total power of EEG 1 hour after a naloxone treatment and that of the matched control group was statistically significant, and the large dose subgroup was more significant than the low-dose group. In the GCS 3 - 5 naloxone treatment group, no significant difference between the total power of EEG of the naloxone group and that of the control group could be observed.CONCLUSION: The low-dose naloxone treatment is helpful enough on the intervention for moderate brain injury, and the large-dose naloxone treatment is better than the low-dose on severe brain injury. For the patients with exceptionally severe brain injury, both the two treatments are proved to have no therapeutic effects.