Pediatric Research(2015)77,674–680
doi:10.1038/pr.2015.31
Minimal systemic hypothermia combined with selective head cooling evaluated in a pig model of hypoxia-ischemia
Nicholas Hoque, Xun Liu, Ela Chakkarapani Marianne Thoresen
Abstract
Background:
Selective head cooling (SHC) with moderate hypothermia (HT) and whole-body cooling are beneficial following perinatal asphyxia. SHC with systemic normothermia (NT) or minimal HT is under-investigated, could obviate systemic complications of moderate HT, and be applicable to preterm infants. We hypothesized that minimal systemic HT with SHC following hypoxia-ischemia (HI) would be neuroprotective compared with systemic NT.
Methods:
Newborn pigs underwent global HI causing permanent brain injury before being randomized to NT (rectal temperature (Trectal) 38.5 °C) or minimal HT (Trectal37.0 °C) with SHC (cooling cap and body wrap) for 48 h followed by 24-h NT with 72-h survival.
Results:
SHC did not reduce global or regional neuropathology score when correcting for insult severity or compared with a NT group matched for HI severity but increased mortality by 26%. During 48 h, the SHC mean &plun; SDTrectalwas 37.0 &plun; 0.2 °C, andTdeep brainandTsuperficial brainwere 35.0 &plun; 1.1 °C and 31.5 &plun; 1.6 °C, respectively, with stableTbrainachieved ≥3 h after starting cooling.
Conclusion:
This is the first study in newborn pigs of minimal systemic HT with SHC for 48 h and a further 24 h of NT following HI. Mortality was increased in the cooled group with no neuroprotection in survivors.