2008 Emily Cooley Memorial Lecture: lessons learned from pediatric transfusion medicine clinical trials . . . a little child shall lead them.
BACKGROUND
Many clinical practices in transfusion medicine are controversial and/or lack definitive guidelines established by sound clinical trials. Although recommendations based on results of clinical trials performed using infants and children may not always be applied directly to adults--and vice versa--lessons learned from pediatric trials can be useful when critically assessing the design/results/conclusions of adult trials.


METHODS
Four randomized clinical trials (RCTs) studying pediatric patients were critically reviewed. They addressed two red blood cell (RBC) transfusion issues: 1) transfusion guidelines by which RBC transfusions are "triggered" by liberal (LIB; high pretransfusion patient hematocrit [Hct] levels) versus being "triggered" by restricted (RES; low pretransfusion Hct levels) and 2) transfusion of fresh RBCs (<or=7 days' storage) versus RBCs (up to 42 days' storage).


RESULTS
Findings established by primary outcomes generally were firm (e.g., fewer RBC transfusions were given to infants/children managed by RES guidelines; transfusing small volumes of RBCs stored up to 42 days to preterm infants diminished allogeneic donor exposures and were equally efficacious and safe as fresh RBCs stored <or=7 days). Findings based on secondary outcomes, subset, and post hoc analyses were inconsistent (e.g., clinical outcomes were equivalent after LIB or RES transfusions in only two of three RCTs; in the third, more neurologic problems were found in neonates given RES transfusions).


CONCLUSIONS
Clinical practices should be based on data pertaining to the primary outcomes of RCTs, because trials are designed and statistically powered to address these issues. Clinical practices suggested by analysis of secondary outcomes, subsets of patients, and post hoc analyses should be applied cautiously until studied further-ideally, as primary outcomes in subsequent RCTs.
Strauss
Ronald G
RG
Department of Pathology, University of Iowa Hospitals & Clinics, Iowa City, Iowa 52242-1009, USA. ronald-strauss@uiowa.edu
D000328:Adult; D000367:Age Factors; D001793:Blood Preservation / Q000379:methods / Q000592:standards; D002648:Child; D002675:Child, Preschool; D017707:Erythrocyte Transfusion / Q000009:adverse effects / Q000592:standards; D004912:Erythrocytes / Q000166:cytology; D017408:Guidelines as Topic; D006400:Hematocrit; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D016032:Randomized Controlled Trials as Topic; D013997:Time Factors