title: Brain Maturity and Variation of Oxygen Extraction in Premature Infants.
abstract: Objectives The ability of the premature brain to extract and use oxygen has not been studied adequately. This study aimed to determine factors that influence fractional tissue oxygen extraction (FTOE) of the brain in premature infants using near-infrared spectroscopy (NIRS) and pulse oximetry. Study Design We prospectively studied FTOE in very low birth weight (BW) infants (< 1,500 g and ≤ 34 weeks' gestation). Factors affecting FTOE and its variability were examined using bivariate and linear regression models. FTOE variability was measured on two scales: short scales (3-20 seconds) and long scales (20-150 seconds). Results We examined 147 simultaneous NIRS and pulse oximetry recordings that were collected from 72 premature infants (gestational age [GA] = 28 weeks and BW = 1,036 g). In regression models, average FTOE correlated negatively with hemoglobin (Hb) and increased significantly in patients with severe intraventricular hemorrhage/periventricular leukomalacia. Both FTOE short- and long-scale variabilities correlated negatively with GA and positively with postnatal age (PNA). Moreover, FTOE long-scale variability was significantly reduced in infants supported with invasive ventilation. Conclusions In premature infants, cerebral oxygen extraction increased with reduced Hb and severe brain injury. Variability in oxygen extraction showed differential changes with GA and PNAs and was affected by invasive ventilation.
authors.affiliation: Department of Pediatric Newborn Medicine, Brigham and Women's Hospital, Boston, Massachusetts.
authors.forename: Mohamed
authors.initials: M
authors.lastname: El-Dib
authors.affiliation: Department of Pediatrics, Children's National Health System, Washington, District of Columbia.
authors.forename: Safwat
authors.initials: S
authors.lastname: Aly
authors.affiliation: Division of Fetal and Transitional Medicine, Children's National Health System, Washington, District of Columbia.
authors.forename: Rathinaswamy
authors.initials: R
authors.lastname: Govindan
authors.affiliation: Division of Newborn Services, The George Washington University Medical Center, and Department of Neonatology, Children's National Health System, Washington, District of Columbia.
authors.forename: Mohamed
authors.initials: M
authors.lastname: Mohamed
authors.affiliation: Division of Fetal and Transitional Medicine, Children's National Health System, and the George Washington University, Washington, District of Columbia.
authors.forename: Adre
authors.initials: A
authors.lastname: du Plessis
authors.affiliation: Division of Newborn Services, The George Washington University Medical Center, and Department of Neonatology, Children's National Health System, Washington, District of Columbia.
authors.forename: Hany
authors.initials: H
authors.lastname: Aly
mesh_terms: D002543:Cerebral Hemorrhage / Q000000981:diagnostic imaging*; D002560:Cerebrovascular Circulation; D004219:District of Columbia; D005260:Female; D005865:Gestational Age; D006454:Hemoglobins / Q000378:metabolism; D006801:Humans; D007231:Infant, Newborn; D007234:Infant, Premature; D019102:Infant, Very Low Birth Weight; D016014:Linear Models; D008297:Male; D008991:Monitoring, Physiologic / Q000379:methods; D010092:Oximetry / Q000379:methods; D010100:Oxygen / Q000097:blood*; D011446:Prospective Studies; D012039:Regional Blood Flow; D019265:Spectroscopy, Near-Infrared; D014463:Ultrasonography
chemical_list: D006454:Hemoglobins; D010100:Oxygen