Study on changes of partial pressure of brain tissue oxygen and brain temperature in acute phase of severe head injury during mild hypothermia therapy

摘要

Objective: To study the changes of partial pressure of brain tissue oxygen ( PbtO_2) and brain temperature in acute phase of severe head injury during mild hypothermia therapy and the clinical significance. Methods: One hundred and sixteen patients with severe head injury were selected and divided into a mild hypothermia group (n =58) , and a control group (n =58) according to odd and even numbers of hospitalization. While mild hypothermia therapy was performed PbtO_2 and brain temperature were monitored for 1-7 days (mean =86 hours), simultaneously, the intracranial pressure, rectum temperature, cerebral perfusion pressure, PaO_2 and PaCO_2 were also monitored. The patients were followed up for 6 months and the prognosis was evaluated with GOS (Glasgow outcome scale). Results: The mean value of PbtO_2 within 24 hour monitoring in the 116 patients was 13.7 mm Hg +- 4.94 mm Hg, lower than the normal value (16 mm Hg +-40 mm Hg) The time of PbtO_2 recovering to the normal value in the mild hypothermia group was shortened by 10 +-4.15 hours compared with the control group (P < 0.05). The survival rate of the mild hypothermia group was 60.43% , higher than that of the control group (46.55%). After the recovery of the brain temperature, PbtO_2 increased with the rise of the brain temperature. Conclusions: Mild hypothermia can improve the survival rate of severe head injury. The technique of monitoring PbtO_2 and the brain temperature is safe and reliable, and has important clinical significance in judging disease condition and instructing clinical therapy.