title: Monitoring regional tissue oxygen extraction in neonates <1250 g helps identify transfusion thresholds independent of hematocrit.
abstract: OBJECTIVE
  We sought to characterize the effects of "booster" packed red blood cell transfusions on multisite regional oxygen saturation in very low birth weight neonates during the first postnatal week and to examine the utility of fractional tissue oxygen extraction as an estimate of tissue oxygenation adequacy.
  
  
  METHODS
  Data were collected in an observational near-infrared spectroscopy (NIRS) pilot survey of 500-1250 g neonates during the first postnatal week. A before-after analysis of "booster" transfusions, defined as empiric 15 mL/kg transfusion following 10 mL/kg cumulative phlebotomy losses, was conducted upon cardiopulmonary, laboratory, and spectroscopy data.
  
  
  RESULTS
  Ten neonates (gestational age 26 ± 0 wk; birth weight 879 ± 49 g) received 14 transfusions at 3 ± 0 postnatal days. Mean hematocrit increased from 35.2 ± 1.2 to 38.5 ± 1.2 % (P < 0.05) following transfusion; pH, base deficit, lactate, creatinine, and cardiopulmonary parameters were unchanged. Cerebral, renal, and splanchnic tissue oxygenation increased 10, 18, and 16%, with concomitant decreases in calculated oxygen extraction of 27, 30, and 9% (all P < 0.05), consistent with enhanced tissue oxygenation. These findings were not observed in a non-transfused comparison group of nine patients.
  
  
  CONCLUSIONS
  "Booster" transfusions improved indices of regional tissue oxygenation while no departures were observed in conventional cardiovascular assessments. We speculate that NIRS-derived oxygenation parameters can provide an objective, graded, and continuous estimate of oxygen delivery-consumption balance not evident using standard monitoring techniques.
authors.affiliation: Department of Pediatrics, Division of Neonatal-Perinatal Medicine, Stony Brook Children's Hospital, Stony Brook, NY, USA.
authors.forename: J P
authors.initials: JP
authors.lastname: Mintzer
authors.affiliation: Department of Pediatrics, Division of Newborn Medicine, The Regional Neonatal Intensive Care Unit, Maria Fareri Children's Hospital at Westchester Medical Center, Valhalla, NY, USA.
authors.forename: B
authors.initials: B
authors.lastname: Parvez
authors.affiliation: Department of Pediatrics, Division of Newborn Medicine, The Regional Neonatal Intensive Care Unit, Maria Fareri Children's Hospital at Westchester Medical Center, Valhalla, NY, USA.
authors.forename: M
authors.initials: M
authors.lastname: Chelala
authors.affiliation: Department of Pediatrics, Division of Newborn Medicine, The Regional Neonatal Intensive Care Unit, Maria Fareri Children's Hospital at Westchester Medical Center, Valhalla, NY, USA.
authors.forename: G
authors.initials: G
authors.lastname: Alpan
authors.affiliation: Department of Pediatrics, Division of Newborn Medicine, The Regional Neonatal Intensive Care Unit, Maria Fareri Children's Hospital at Westchester Medical Center, Valhalla, NY, USA.
authors.forename: E F
authors.initials: EF
authors.lastname: LaGamma
mesh_terms: D034841:Abdominal Cavity / Q000098:blood supply*; D000751:Anemia, Neonatal / Q000378:metabolism / Q000628:therapy*; D015415:Biomarkers / Q000378:metabolism; D001921:Brain / Q000378:metabolism*; D017707:Erythrocyte Transfusion; D005260:Female; D006400:Hematocrit; D006801:Humans; D007231:Infant, Newborn; D007234:Infant, Premature; D019102:Infant, Very Low Birth Weight; D007668:Kidney / Q000378:metabolism*; D008297:Male; D008991:Monitoring, Physiologic; D010092:Oximetry; D010100:Oxygen / Q000378:metabolism*; D018579:Patient Selection; D010865:Pilot Projects; D017410:Practice Guidelines as Topic; D019265:Spectroscopy, Near-Infrared; D013152:Splanchnic Circulation; D013997:Time Factors; D016896:Treatment Outcome
chemical_list: D015415:Biomarkers; D010100:Oxygen
keywords: Oxygen extraction; near-infrared spectroscopy; oxygen delivery; red cell mass; “booster” transfusion