title: Blood transfusions increase cerebral, splanchnic, and renal oxygenation in anemic preterm infants.
abstract: BACKGROUND
  Multiprobe near infrared spectroscopy (NIRS) has been used to study regional cerebral (rSO(2)C), splanchnic (rSO(2)S), and renal (rSO(2)R) tissue oxygenation in newborns. We used this method to study the effects of red blood cell (RBC) transfusions in anemic preterm infants to assess if thresholds for transfusions were appropriate for recognizing a clinical condition permitting tissue oxygenation improvement.
  
  
  METHODS
  Multiprobe NIRS (INVOS 5100, Somanetics) was applied during transfusion to 15 preterm infants with symptomatic anemia of prematurity (hematocrit level of <25%). rSO(2)C, rSO(2)S, and rSO(2)R were recorded at selected times, and then fractional oxygen cerebral extraction ratio [FOEC: (SaO(2)-rSO(2)C)/SaO(2)], fractional oxygen splanchnic extraction ratio [FOES: (SaO(2)-rSO(2)S)/SaO(2)], fractional oxygen renal extraction ratio [FOER: (SaO(2)-rSO(2)R)/SaO(2)], cerebrosplanchnic oxygenation ratio [CSOR: (rSO(2)S/rSO(2)C)], and cerebrorenal oxygenation ratio [CROR: (rSO(2)R/rSO(2)C)] were calculated. In addition, we used Doppler ultrasonography for evaluating cerebral blood flow (CBF), splanchnic blood flow (SBF), and renal blood flow (RBF) velocity.
  
  
  RESULTS
  rSO(2)C, rSO(2)S, and rSO(2)R significantly increased during transfusions, while FOEC, FOES, and FOER decreased. CSOR and CROR increased during transfusions. CBF velocity decreased during the study period, while SBF and RBF velocities did not vary.
  
  
  CONCLUSIONS
  RBC transfusions performed at used thresholds permitted an increase in cerebral, splanchnic, and renal oxygenation. The associated decreases in oxygen tissue extraction might suggest that transfusions were well timed for preventing tissue hypoxia or too early and theoretically prooxidant. Further studies could help to clarify this issue.
authors.affiliation: Department of Surgical and Medical Critical Care, Section of Neonatology, Careggi University Hospital of Florence, Florence, Italy. cdani@unifi.it
authors.forename: Carlo
authors.initials: C
authors.lastname: Dani
authors.forename: Simone
authors.initials: S
authors.lastname: Pratesi
authors.forename: Giulia
authors.initials: G
authors.lastname: Fontanelli
authors.forename: Jacopo
authors.initials: J
authors.lastname: Barp
authors.forename: Giovanna
authors.initials: G
authors.lastname: Bertini
mesh_terms: D000751:Anemia, Neonatal / Q000378:metabolism* / Q000628:therapy*; D002531:Cerebellum / Q000378:metabolism*; D017707:Erythrocyte Transfusion; D005260:Female; D006801:Humans; D007231:Infant, Newborn; D007234:Infant, Premature / Q000378:metabolism*; D007668:Kidney / Q000378:metabolism*; D008297:Male; D010101:Oxygen Consumption; D019265:Spectroscopy, Near-Infrared