RT Journal Article SR Electronic T1 The chicken or the egg? Further characterisation of the relationship between major intraventricular-periventricular haemorrhage and thrombocytopenia in preterm infants JF Archives of Disease in Childhood JO Arch Dis Child FD BMJ Publishing Group Ltd and Royal College of Paediatrics and Child Health SP A90 OP A91 DO 10.1136/archdischild-2012-301885.217 VO 97 IS Suppl 1 A1 JP Lewis A1 D Abdulkarim A1 J Jones A1 P Clarke YR 2012 UL http://adc.bmj.com/content/97/Suppl_1/A90.3.abstract AB Background and aim Thrombocytopenia has been linked to an increased risk of major intraventricular-periventricular haemorrhage (IVH-PVH) in preterm neonates. Recent studies observing neonatal thrombocytopenia found no causative relationship between severe thrombocytopenia and major haemorrhage, but confirmation whether IVH-PVH is a cause or effect of thrombocytopenia is lacking. We aimed to determine the temporal relationship between the timing of major bleeding and significant thrombocytopenia (platelet count <100 x109/L) in neonates with major IVH-PVH. Methods Retrospective review of all neonates admitted to our neonatal unit between 01/01/2005 and 31/12/2010 who had major IVH-PVH. We analysed case notes, haematology results, and cranial ultrasonograms to determine, where possible, the timing of each infant's IVH-PVH based on acute clinical symptoms, significant fall in haemoglobin concentration, and appearances on ultrasonograms. We recorded platelet counts from up to 3 days before and 7 days after the major IVH-PVH. Results Complete data were available for 48/64 (75%) neonates in the 6-year study period. 22/48 (46%) neonates already had major IVH-PVH evident on their very first ultrasonogram and therefore had no definite pre-bleed platelet count available. 26/48 (54%) neonates with an initial normal ultrasonogram had major IVH-PVH on subsequent ultrasonography, with the haemorrhage occurring at a median postnatal age of 27 hours. Of these, only 3/26 (12%) were already significantly thrombocytopenic before their IVH-PVH (pre-bleed platelet count range: 53-75×109/L), 21/26 (81%) became significantly thrombocytopenic post the IVH-PVH (with median nadir post-bleed platelet count 40 x109/L [range: 7-99×109/L]), and only 2/26 (8%) maintained a platelet count of >100 x109/L in the wake of the major IVH-PVH. Of 22 infants with definite pre- and post-bleed platelet counts available, the median fell from 146 x109/L pre-bleed (range 40-318×109/L), to a nadir of median 46 x109/L post-bleed (range 7-252×109/L). Conclusion Most preterm neonates who develop major IVH-PVH become significantly thrombocytopenic as a direct consequence of the bleeding event. These data imply that prophylactically transfusing platelets to thrombocytopenic neonates in an attempt to prevent major intraventricular haemorrhage is belated.