TY - JOUR
T1 - Modest hypothermia provides partial neuroprotection when used for immediate resuscitation after brain ischemia
AU - Laptook, Abbot R.
AU - Corbett, Ronald J T
AU - Sterett, Rick
AU - Burns, Dennis K.
AU - Garcia, Damian
AU - Tollefsbol, Greg
PY - 1997/7
Y1 - 1997/7
N2 - Intraischemic reduction in temperature of 2-3°C (modest hypothermia) has been demonstrated to provide partial neuroprotection in neonatal animals. This investigation determined if modest hypothermia initiated immediately after brain ischemia provides neuroprotection. Piglets were studied with rectal temperature maintained during the 1st h after 15 min of brain ischemia at either 38.3 ± 0.3°C (normothermia, n = 11) or at 35.8 ± 0.5°C (modest hypothermia, n = 11). The severity of brain ischemia was similar between groups as indicated by equivalent reduction in mean blood pressure (90 ± 15 to 24 ± 3 versus 92 ± 13 to 26 ± 3 mm Hg), and changes in cerebral metabolites and intracellular pH (pH(i)) measured by magnetic resonance spectroscopy (β-nucleoside triphosphate = 44 ± 9 versus 42 ± 18% of control, control = 100%, pH(i): 6.25 ± .15 versus 6.24 ± 0.22 for normothermic and modestly hypothermic groups, respectively). In the first 90 min after ischemia, there were no differences between groups in the duration and extent of brain acidosis, and relative concentrations of phosphorylated metabolites. Categorical assessment of neurobehavior was evaluated at 72 h postischemia (n = 16), or earlier if an animal's condition deteriorated (n = 6). Postischemic hypothermia was associated with less severe stages of encephalopathy compared with normothermia (p = 0.05). Histologic neuronal injury was assessed categorically in 16 brain regions, and postischemic hypothermia resulted in less neuronal injury in temporal (p = 0.024) and occipital (p = 0.044) cortex at 10 mm beneath the cortical surface, and in the basal ganglia (p = 0.038) compared with that in normothermia. Modest hypothermia for 1 h immediately after brain ischemia provides partial neuroprotection and may represent an adjunct to resuscitative strategies.
AB - Intraischemic reduction in temperature of 2-3°C (modest hypothermia) has been demonstrated to provide partial neuroprotection in neonatal animals. This investigation determined if modest hypothermia initiated immediately after brain ischemia provides neuroprotection. Piglets were studied with rectal temperature maintained during the 1st h after 15 min of brain ischemia at either 38.3 ± 0.3°C (normothermia, n = 11) or at 35.8 ± 0.5°C (modest hypothermia, n = 11). The severity of brain ischemia was similar between groups as indicated by equivalent reduction in mean blood pressure (90 ± 15 to 24 ± 3 versus 92 ± 13 to 26 ± 3 mm Hg), and changes in cerebral metabolites and intracellular pH (pH(i)) measured by magnetic resonance spectroscopy (β-nucleoside triphosphate = 44 ± 9 versus 42 ± 18% of control, control = 100%, pH(i): 6.25 ± .15 versus 6.24 ± 0.22 for normothermic and modestly hypothermic groups, respectively). In the first 90 min after ischemia, there were no differences between groups in the duration and extent of brain acidosis, and relative concentrations of phosphorylated metabolites. Categorical assessment of neurobehavior was evaluated at 72 h postischemia (n = 16), or earlier if an animal's condition deteriorated (n = 6). Postischemic hypothermia was associated with less severe stages of encephalopathy compared with normothermia (p = 0.05). Histologic neuronal injury was assessed categorically in 16 brain regions, and postischemic hypothermia resulted in less neuronal injury in temporal (p = 0.024) and occipital (p = 0.044) cortex at 10 mm beneath the cortical surface, and in the basal ganglia (p = 0.038) compared with that in normothermia. Modest hypothermia for 1 h immediately after brain ischemia provides partial neuroprotection and may represent an adjunct to resuscitative strategies.
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U2 - 10.1203/00006450-199707000-00004
DO - 10.1203/00006450-199707000-00004
M3 - Article
C2 - 9212032
AN - SCOPUS:0030992023
SN - 0031-3998
VL - 42
SP - 17
EP - 23
JO - Pediatric Research
JF - Pediatric Research
IS - 1
ER -