title: Brain temperature in neonates with hypoxic-ischemic encephalopathy during therapeutic hypothermia.
abstract: OBJECTIVE
  To noninvasively determine brain temperature of neonates with hypoxic-ischemic encephalopathy (HIE) during and after therapeutic hypothermia.
  
  
  METHODS
  Using a phantom, we derived a calibration curve to calculate brain temperature based on chemical shift differences in magnetic resonance spectroscopy. We enrolled infants admitted for therapeutic hypothermia and assigned them to a moderate HIE (M-HIE) or severe HIE (S-HIE) group based on Sarnat staging. Rectal (core) temperature and magnetic resonance spectroscopy data used to derive regional brain temperatures (basal ganglia, thalamus, and cortical gray matter) were acquired concomitantly during and after therapeutic hypothermia. We compared brain and rectal temperature in the M-HIE and S-HIE groups during and after therapeutic hypothermia using 2-tailed t-tests.
  
  
  RESULTS
  Eighteen patients (14 with M-HIE and 4 with S-HIE) were enrolled. As expected, both brain and rectal temperatures were lower during therapeutic hypothermia than after therapeutic hypothermia. Brain temperature in patients with S-HIE was higher than in those with M-HIE both during (35.1 ± 1.3°C vs 33.7 ± 1.2°C; P < .01) and after therapeutic hypothermia (38.1 ± 1.5°C vs 36.8 ± 1.3°C; P < .01). The brain-rectal temperature gradient was also greater in the S-HIE group both during and after therapeutic hypothermia.
  
  
  CONCLUSIONS
  For this analysis of a small number of patients, brain temperature and brain-rectal temperature gradient were higher in neonates with S-HIE than in those with M-HIE during and after therapeutic hypothermia. Further studies are needed to determine whether further decreasing brain temperature in neonates with S-HIE is safe and effective in improving outcome.
authors.affiliation: Division of Neonatal Medicine, Department of Pediatrics, Center for Fetal and Neonatal Medicine, Children's Hospital Los Angeles, Keck School of Medicine, University of Southern California, Los Angeles, CA. Electronic address: wutcz8@gmail.com.
authors.forename: Tai-Wei
authors.initials: TW
authors.lastname: Wu
authors.affiliation: Division of Neonatal Medicine, Department of Pediatrics, Center for Fetal and Neonatal Medicine, Children's Hospital Los Angeles, Keck School of Medicine, University of Southern California, Los Angeles, CA.
authors.forename: Claire
authors.initials: C
authors.lastname: McLean
authors.affiliation: Division of Neonatal Medicine, Department of Pediatrics, Center for Fetal and Neonatal Medicine, Children's Hospital Los Angeles, Keck School of Medicine, University of Southern California, Los Angeles, CA.
authors.forename: Philippe
authors.initials: P
authors.lastname: Friedlich
authors.affiliation: Department of Radiology, Children's Hospital Los Angeles, Keck School of Medicine, University of Southern California, Los Angeles, CA.
authors.forename: Jessica
authors.initials: J
authors.lastname: Wisnowski
authors.affiliation: Department of Radiology, Children's Hospital Los Angeles, Keck School of Medicine, University of Southern California, Los Angeles, CA.
authors.forename: John
authors.initials: J
authors.lastname: Grimm
authors.affiliation: Department of Radiology, Children's Hospital Los Angeles, Keck School of Medicine, University of Southern California, Los Angeles, CA.
authors.forename: Ashok
authors.initials: A
authors.lastname: Panigrahy
authors.affiliation: Department of Radiology, Children's Hospital Los Angeles, Keck School of Medicine, University of Southern California, Los Angeles, CA.
authors.forename: Stefan
authors.initials: S
authors.lastname: Bluml
authors.affiliation: Division of Neonatal Medicine, Department of Pediatrics, Center for Fetal and Neonatal Medicine, Children's Hospital Los Angeles, Keck School of Medicine, University of Southern California, Los Angeles, CA.
authors.forename: Istvan
authors.initials: I
authors.lastname: Seri
mesh_terms: D001831:Body Temperature; D001921:Brain / Q000502:physiology*; D005260:Female; D006801:Humans; D007036:Hypothermia, Induced; D020925:Hypoxia-Ischemia, Brain / Q000503:physiopathology* / Q000628:therapy*; D007231:Infant, Newborn; D008279:Magnetic Resonance Imaging; D009682:Magnetic Resonance Spectroscopy; D012007:Rectum / Q000503:physiopathology; D015203:Reproducibility of Results