Are thrombocytopenia and platelet transfusions associated with major bleeding in preterm neonates? A systematic review

Over 75% of severely thrombocytopenic preterm neonates receive platelet transfusions to prevent bleeding, but transfusion guidelines are based mainly on expert opinion. The aim of this review was to investigate whether platelet counts, platelet transfusions or platelet indices are associated with major bleeding in preterm neonates. We performed a systematic search of the EMBASE and MEDLINE databases until December 2017. We included randomized trials, cohort and case control studies. (Prospero: CRD42015013399). We screened 8734 abstracts and 1225 fulltexts, identifying 36 eligible studies. In 30, timing of the platelet counts or transfusions in relation to the bleeding was unclear. Of the remaining six studies, two showed that thrombocytopenia was associated with increased risk of bleeding, two showed no such assocation, and three showed lack of an association between platelet transfusions and bleeding risk. No studies assessing platelet indices were found. The study results suggest that prophylactic platelet transfusions may not reduce bleeding risk in preterm neonates.