Abstract 2046 Neuroprotective Strategies for Hypoxic-Ischemic Encephalopathy Platform, Sunday, 5/2

Background: Previously, in studies of 3 or 12 h post-hypoxic hypothermia used as neuroprotective intervention, the damage to other organs than to the brain were similar in the NT or HT groups. Clinically there is a worry of adverse effect of HT, however, HT might also be protective to other organs than the brain.

Aim: To investigate whether 24 h mild post-hypoxic HT has any effect on organ damage in newborn pigs subjected to a severe global HI insult and surviving 72 h.

Methods: Newborn pigs, <48 h old, were anesthetized, ventilated and subjected to a 45 min global HI insult by reducing FiO2 (≈ 6%) until EEG was lo amplitude. On reoxygenation 18 were maintained NT (39°C) for 72 h and 18 were cooled to 35.0°C for 24 h followed by 48 h NT. The organs were immersion fixed and examined using light microscopy and the degree of the damage decided on a scale 0-3.

Results: The number of animals which presented with damage in individual organs is listed in the table. There was no significant difference in occurrence of organ pathology in the two groups. There was a trend of more lung pathology in the HT group. The clinical significance of this was that more HT than NT animals needed O2 after 24 h (8/18 vs. 2/18), however, this normalized after HT resumed and all animals were well ventilated in air at 48 h. For the heart, there was a trend that the ischemic lesions were smaller in the HT animals. There were no major complications like bleeding or infection in any group.

Table 1 No caption available
Full size table

Conclusion: We found no difference in adverse effects or occurrence of organ pathology in newborn pigs who were subjected to 24 h mild HT or NT after a severe global HI insult.