RT Journal Article SR Electronic T1 Two-year outcomes following a randomised platelet transfusion trial in preterm infants JF Archives of Disease in Childhood - Fetal and Neonatal Edition JO Arch Dis Child Fetal Neonatal Ed FD BMJ Publishing Group Ltd and Royal College of Paediatrics and Child Health SP 452 OP 457 DO 10.1136/archdischild-2022-324915 VO 108 IS 5 A1 Moore, Carmel Maria A1 D’Amore, Angela A1 Fustolo-Gunnink, Suzanne A1 Hudson, Cara A1 Newton, Alice A1 Santamaria, Beatriz Lopez A1 Deary, Alison A1 Hodge, Renate A1 Hopkins, Valerie A1 Mora, Ana A1 Llewelyn, Charlotte A1 Venkatesh, Vidheya A1 Khan, Rizwan A1 Willoughby, Karen A1 Onland, Wes A1 Fijnvandraat, Karin A1 New, Helen V A1 Clarke, Paul A1 Lopriore, Enrico A1 Watts, Timothy A1 Stanworth, Simon A1 Curley, Anna A1 YR 2023 UL http://fn.bmj.com/content/108/5/452.abstract AB Objective Assess mortality and neurodevelopmental outcomes at 2 years of corrected age in children who participated in the PlaNeT-2/MATISSE (Platelets for Neonatal Transfusion - 2/Management of Thrombocytopenia in Special Subgroup) study, which reported that a higher platelet transfusion threshold was associated with significantly increased mortality or major bleeding compared to a lower one.Design Randomised clinical trial, enrolling from June 2011 to August 2017. Follow-up was complete by January 2020. Caregivers were not blinded; however, outcome assessors were blinded to treatment group.Setting 43 level II/III/IV neonatal intensive care units (NICUs) across UK, Netherlands and Ireland.Patients 660 infants born at less than 34 weeks’ gestation with platelet counts less than 50×109/L.Interventions Infants were randomised to undergo a platelet transfusion at platelet count thresholds of 50×109/L (higher threshold group) or 25×109/L (lower threshold group).Main outcomes measures Our prespecified long-term follow-up outcome was a composite of death or neurodevelopmental impairment (developmental delay, cerebral palsy, seizure disorder, profound hearing or vision loss) at 2 years of corrected age.Results Follow-up data were available for 601 of 653 (92%) eligible participants. Of the 296 infants assigned to the higher threshold group, 147 (50%) died or survived with neurodevelopmental impairment, as compared with 120 (39%) of 305 infants assigned to the lower threshold group (OR 1.54, 95% CI 1.09 to 2.17, p=0.017).Conclusions Infants randomised to a higher platelet transfusion threshold of 50×109/L compared with 25×109/L had a higher rate of death or significant neurodevelopmental impairment at a corrected age of 2 years. This further supports evidence of harm caused by high prophylactic platelet transfusion thresholds in preterm infants.Trial registration number ISRCTN87736839.Data are available upon reasonable request. Data will be available upon reasonable request, with approval of the trial group.