Effect of Hypothermia on Hypoxic-Ischemic (HI) Brain Damage in Neonatal Rats 174

Background. The brain energy metabolism of severly birth-asphyxlated human infants shows a secondary energy fallure (SEF) after 2-4 days.

Aim: To study the effect of hypothermia on the severity of brain damage and outcome after Hl injury using magnetic resonance (MR).Subjects: 3 groups of 7-d old SD rats. Interventions. After right common carotid artery ligation, 1 h rest and 1.5 h hypoxia (8% O₂), group 1 (n=8) was kept normothermic (37 °C) and group 2 (n=8) hypothermic (30 °C) for 24 h. Group 3 served as control. Between 18 and 30 h after hypoxia 31P-spectra of the right hemisphere were acquired (2 Tesla-MR-system) with a surface-coil. At 30 h the volume of the brain edema, and at 4 d the necrotic volume were assessed by MR imaging.Table

Table 1

Conclusions. 24 h of hypothermla ameliorates the secondary energy failure and reduces the infarcted volume significantly in proportion to the extension of the edema. Thus, hypothermia has a significant brain protective effect after Hl.