Mild hypothermia after severe transient hypoxia-ischemia ameliorates delayed cerebral energy failure in the newborn piglet

Pediatr Res. 1995 May;37(5):667-70. doi: 10.1203/00006450-199505000-00019.


Severely birth-asphyxiated human infants develop delayed ("secondary") cerebral energy failure, which carries a poor prognosis, during the first few days of life. This study tested the hypothesis that mild hypothermia after severe transient cerebral hypoxia-ischemia decreases the severity of delayed energy failure in the newborn piglet. Six piglets underwent temporary occlusion of the common carotid arteries and hypoxemia. Resuscitation was started when cerebral [phosphocreatine (PCr)]/[inorganic phosphate (Pi)] as determined by phosphorus magnetic resonance spectroscopy had fallen almost to zero and [nucleotide triphosphate (NTP)]/[exchangeable phosphate pool (EPP)] had fallen below about 30% of baseline. Rectal and tympanic temperatures were then reduced to 35 degrees C for 12 h after which normothermia (38.5 degrees C) was resumed. Spectroscopy results over the next 64 h were compared with previously established data from 12 piglets similarly subjected to transient cerebral hypoxia-ischemia, but maintained normothermic, and six sham-operated controls. The mean severity of the primary insult (judged by the time integral of depletion of [NTP]/[EPP]) was similar in the hypothermic and normothermic groups. In the normothermic group, [PCr]/[Pi] and [NTP]/[EPP] recovered after the acute insult and then fell again. Minimum values for these variables observed between 24 and 48 h were significantly higher in the hypothermic group and not significantly different from the control values (p < 0.05, analysis of variance). A large reduction in secondary energy failure relative to the extent of the primary insult was shown and no further fall in either [PCr]/[Pi] or [NTP]/[EPP] took place up to 64 h in the hypothermic piglets.(ABSTRACT TRUNCATED AT 250 WORDS)

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Acute Disease
  • Animals
  • Animals, Newborn
  • Cerebral Cortex / metabolism*
  • Energy Metabolism
  • Hypothermia, Induced*
  • Hypoxia, Brain / metabolism
  • Hypoxia, Brain / physiopathology
  • Hypoxia, Brain / therapy*
  • Ischemic Attack, Transient / metabolism
  • Ischemic Attack, Transient / physiopathology
  • Ischemic Attack, Transient / therapy*
  • Phosphates / metabolism
  • Phosphocreatine / metabolism
  • Swine


  • Phosphates
  • Phosphocreatine