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bioRxiv · 10.1101/2020.02.25.964288

Intravenous edaravone plus therapeutic hypothermia offers limited neuroprotection in the hypoxic-ischaemic newborn piglet

Abstract

Therapeutic hypothermia is a standard therapy for neonatal hypoxic-ischaemic encephalopathy. One potential additional therapy is the free radical scavenger edaravone (3-methyl-1-phenyl-2-pyrazolin-5-one). To compare the neuroprotective effects of edaravone plus therapeutic hypothermia with those of therapeutic hypothermia alone after a hypoxic-ischaemic insult in the newborn piglet, anaesthetized piglets were subjected to 40 min of hypoxia (3-5% inspired oxygen) and cerebral ischaemia was assessed by cerebral blood volume. Body temperature was maintained at 38.5 {degrees}C in the normothermia group (NT, n = 8) and at 34 {degrees}C (24 h after the insult) in the therapeutic hypothermia (TH, n = 7) and therapeutic hypothermia plus edaravone (3 mg intravenous every 12 h for 3 days after the insult; TH+EV, n = 6) groups under mechanical ventilation. Five days after the insult, the mean (standard deviation) neurological scores were 10.9 (5.7) in the NT group, 17.0 (0.4) in the TH group (p = 0.025 vs. NT) and 15.0 (3.9) in the TH+EV group. The histopathological score of the TH+EV group showed no significant improvement compared with that of the other groups. In conclusion, edaravone plus therapeutic hypothermia had no additive neuroprotective effects after hypoxia-ischaemia in neurological and histopathological assessments.

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BibTeXRIS

Yamato, S., Nakamura, S., Htun, Y., Nakamura, M., Jinnai, W., Nakao, Y., Mitsuie, T., Koyano, K., Wakabayashi, T., Morimoto, A. H., Sugino, M., Iwase, T., Kondo, S. I., Yasuda, S., Ueno, M., Miki, T., Kusaka, T.. 2020-02-25. Intravenous edaravone plus therapeutic hypothermia offers limited neuroprotection in the hypoxic-ischaemic newborn piglet. https://doi.org/10.1101/2020.02.25.964288

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