title: Randomized trial of hematocrit 25% versus 35% during hypothermic cardiopulmonary bypass in infant heart surgery.
abstract: OBJECTIVE
  We previously reported that postoperative hemodynamics and developmental outcomes were better among infants randomized to a higher hematocrit value during hypothermic cardiopulmonary bypass. However, worse outcomes were concentrated in patients with hematocrit values of 20% or below, and the benefits of hematocrit values higher than 25% were uncertain.
  
  
  METHODS
  We compared perioperative hemodynamics and, at 1 year, developmental outcome and brain magnetic resonance imaging in a single-center, randomized trial of hemodilution to a hematocrit value of 25% versus 35% during hypothermic radiopulmonary bypass for reparative heart surgery in infants undergoing 2-ventricle repairs without aortic arch obstruction.
  
  
  RESULTS
  Among 124 subjects, 56 were assigned to the lower-hematocrit strategy (24.8% +/- 3.1%, mean +/- SD) and 68 to the higher-hematocrit strategy (32.6% +/- 3.5%). Infants randomized to the 25% strategy, compared with the 35% strategy, had a more positive intraoperative fluid balance (P = .007) and lower regional cerebral oxygen saturation at 10 minutes after cooling (P = .04) and onset of low flow (P = .03). Infants with dextro-transposition of the great arteries in the 25% group had significantly longer hospital stay. Other postoperative outcomes, blood product usage, and adverse events were similar in the treatment groups. At age 1 year (n = 106), the treatment groups had similar scores on the Psychomotor and Mental Development Indexes of the Bayley Scales; both groups scored significantly worse than population norms.
  
  
  CONCLUSIONS
  Hemodilution to hematocrit levels of 35% compared with those of 25% had no major benefits or risks overall among infants undergoing 2-ventricle repair. Developmental outcomes at age 1 year in both randomized groups were below those in the normative population.
authors.affiliation: Department of Cardiology, Children's Hospital Boston, Boston, Mass 02115, USA. jane.newburger@cardio.chboston.org
authors.forename: Jane W
authors.initials: JW
authors.lastname: Newburger
authors.forename: Richard A
authors.initials: RA
authors.lastname: Jonas
authors.forename: Janet
authors.initials: J
authors.lastname: Soul
authors.forename: Barry D
authors.initials: BD
authors.lastname: Kussman
authors.forename: David C
authors.initials: DC
authors.lastname: Bellinger
authors.forename: Peter C
authors.initials: PC
authors.lastname: Laussen
authors.forename: Richard
authors.initials: R
authors.lastname: Robertson
authors.forename: John E
authors.initials: JE
authors.lastname: Mayer
authors.forename: Pedro J
authors.initials: PJ
authors.lastname: del Nido
authors.forename: Emile A
authors.initials: EA
authors.lastname: Bacha
authors.forename: Joseph M
authors.initials: JM
authors.lastname: Forbess
authors.forename: Frank
authors.initials: F
authors.lastname: Pigula
authors.forename: Stephen J
authors.initials: SJ
authors.lastname: Roth
authors.forename: Karen J
authors.initials: KJ
authors.lastname: Visconti
authors.forename: Adre J
authors.initials: AJ
authors.lastname: du Plessis
authors.forename: David M
authors.initials: DM
authors.lastname: Farrell
authors.forename: Ellen
authors.initials: E
authors.lastname: McGrath
authors.forename: Leonard A
authors.initials: LA
authors.lastname: Rappaport
authors.forename: David
authors.initials: D
authors.lastname: Wypij
mesh_terms: D006348:Cardiac Surgical Procedures / Q000009:adverse effects / Q000379:methods; D002315:Cardiopulmonary Bypass / Q000009:adverse effects / Q000379:methods*; D002423:Cause of Death; D002493:Central Nervous System Diseases / Q000453:epidemiology / Q000209:etiology; D002658:Developmental Disabilities / Q000453:epidemiology / Q000209:etiology / Q000517:prevention & control*; D005260:Female; D005500:Follow-Up Studies; D006330:Heart Defects, Congenital / Q000175:diagnosis / Q000401:mortality* / Q000601:surgery*; D006345:Heart Septal Defects, Ventricular / Q000175:diagnosis / Q000401:mortality / Q000601:surgery; D006400:Hematocrit; D006438:Hemodilution / Q000009:adverse effects*; D006801:Humans; D007036:Hypothermia, Induced; D015994:Incidence; D007223:Infant; D008297:Male; D011183:Postoperative Complications / Q000453:epidemiology; D011336:Probability; D018570:Risk Assessment; D016019:Survival Analysis; D013771:Tetralogy of Fallot / Q000175:diagnosis / Q000401:mortality / Q000601:surgery; D013997:Time Factors; D014188:Transposition of Great Vessels / Q000175:diagnosis / Q000401:mortality / Q000601:surgery; D016896:Treatment Outcome