title: Relationship Between Cerebral Oxygenation and Metabolism During Rewarming in Newborn Infants After Therapeutic Hypothermia Following Hypoxic-Ischemic Brain Injury.
abstract: Therapeutic hypothermia (TH) has become a standard of care following hypoxic ischemic encephalopathy (HIE). After TH, body temperature is brought back to 37 °C over 14 h. Lactate/N-acetylasperatate (Lac/NAA) peak area ratio on proton magnetic resonance spectroscopy ((1)H MRS) is the best available outcome biomarker following HIE. We hypothesized that broadband near infrared spectroscopy (NIRS) measured changes in the oxidation state of cytochrome-c-oxidase concentration (Δ[oxCCO]) and cerebral hemodynamics during rewarming would relate to Lac/NAA. Broadband NIRS and systemic data were collected during rewarming from 14 infants following HIE over a mean period of 12.5 h. (1)H MRS was performed on day 5-9. Heart rate increased by 20/min during rewarming while blood pressure and peripheral oxygen saturation (SpO2) remained stable. The relationship between mitochondrial metabolism and oxygenation (measured as Δ[oxCCO] and Δ[HbD], respectively) was calculated by linear regression analysis. This was reviewed in three groups: Lac/NAA values <0.5, 0.5-1, >1. Mean regression coefficient (r (2)) values in these groups were 0.41 (±0.27), 0.22 (±0.21) and 0.01, respectively. The relationship between mitochondrial metabolism and oxygenation became impaired with rising Lac/NAA. Cardiovascular parameters remained stable during rewarming.
authors.affiliation: Institute for Women's Health, University College London and Neonatal Unit, University College London Hospitals Trust, London, UK. subhabratamitra@hotmail.com.
authors.forename: Subhabrata
authors.initials: S
authors.lastname: Mitra
authors.affiliation: Biomedical Optics Research Laboratory, Department of Medical Physics and Biomedical Engineering, University College London, London, UK.
authors.forename: Gemma
authors.initials: G
authors.lastname: Bale
authors.affiliation: Institute for Women's Health, University College London and Neonatal Unit, University College London Hospitals Trust, London, UK.
authors.forename: Judith
authors.initials: J
authors.lastname: Meek
authors.affiliation: Institute for Women's Health, University College London and Neonatal Unit, University College London Hospitals Trust, London, UK.
authors.forename: Cristina
authors.initials: C
authors.lastname: Uria-Avellanal
authors.affiliation: Institute for Women's Health, University College London and Neonatal Unit, University College London Hospitals Trust, London, UK.
authors.forename: Nicola J
authors.initials: NJ
authors.lastname: Robertson
authors.affiliation: Biomedical Optics Research Laboratory, Department of Medical Physics and Biomedical Engineering, University College London, London, UK.
authors.forename: Ilias
authors.initials: I
authors.lastname: Tachtsidis
mesh_terms: D001224:Aspartic Acid / Q000031:analogs & derivatives / Q000378:metabolism; D015415:Biomarkers / Q000097:blood; D001833:Body Temperature Regulation; D002560:Cerebrovascular Circulation; D003576:Electron Transport Complex IV / Q000378:metabolism*; D005260:Female; D006454:Hemoglobins / Q000378:metabolism; D006801:Humans; D007036:Hypothermia, Induced; D020925:Hypoxia-Ischemia, Brain / Q000097:blood / Q000503:physiopathology / Q000628:therapy*; D007231:Infant, Newborn; D019344:Lactic Acid / Q000378:metabolism; D016014:Linear Models; D008297:Male; D008928:Mitochondria / Q000378:metabolism; D010084:Oxidation-Reduction; D010092:Oximetry / Q000379:methods; D010100:Oxygen / Q000097:blood*; D010101:Oxygen Consumption; D011237:Predictive Value of Tests; D066244:Proton Magnetic Resonance Spectroscopy; D017694:Rewarming; D019265:Spectroscopy, Near-Infrared; D013997:Time Factors; D016896:Treatment Outcome
chemical_list: D015415:Biomarkers; D006454:Hemoglobins; D001224:Aspartic Acid; D019344:Lactic Acid; C000179:N-acetylaspartate; D003576:Electron Transport Complex IV; D010100:Oxygen
keywords: Cerebral metabolism; Cerebral oxygenation; Cytochrome-c-oxidase; Hypoxic-ischaemic brain injury; Newborn infant