The Role of Platelets in Premature Neonates with Intraventricular Hemorrhage: A Systematic Review and Meta-Analysis

Abstract

Intraventricular hemorrhage (IVH) affects up to 22% of extremely low birth weight neonates. Impaired coagulation might contribute to the pathogenesis of IVH. The aims of this study were to summarize the current knowledge on the role of platelet indices in premature neonates with IVH and to provide an overview of secondary hemostasis parameters as well as fibrinolysis in premature neonates with IVH. The review was conducted in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. The databases PubMed, Embase, Scopus, and Web of Science were searched on March 7, 2019, without time restrictions. In total, 30 studies were included. Most studies investigated the significance of platelet counts and/or mean platelet volume (MPV). The meta-analysis showed that at day 1 of life, neither platelet count nor MPV differed significantly between neonates with or without IVH (standardized mean difference [SMD]: –0.15 × 109/L, 95% confidence interval [CI]: –0.37 to 0.07 and SMD: 0.22 fl, 95% CI: –0.07 to 0.51, respectively). However, platelet counts < 100 × 109/L were associated with an increased risk of IVH. Secondary hemostasis parameters did not differ between neonates with and without IVH. Fibrinolysis was only sparsely investigated. In conclusion, platelet counts < 100 × 109/L were associated with an increased risk of IVH in premature neonates. The impact of secondary hemostasis was only sparsely investigated but seemed to be minor, and the role of fibrinolysis in IVH in premature neonates needs further research. Whether reduced platelet function is associated with an increased risk of IVH in premature neonates remains to be investigated.

Neonatal Sepsis and Hemostasis

“…Hemorrhage in preterm neonates is often observed in parallel with thrombocytopenia, without any apparent causality between platelet count and bleeding risk [ 73 ]. Thrombocytopenia does not stand alone as a risk factor for bleeding events, and thus there is a need to develop laboratory tests to provide a better correlation with bleeding risk other than platelet count alone, especially tests that focus mainly on platelet function.…”

Reduced platelet function in preterm neonates compared with term neonates

“…The etiology of IVH is incompletely understood, but it is believed to be multifactorial 8–11 . Thrombocytopenia affects up to 70% of preterm neonates with birthweight <1000 g, 12 and studies have found that IVH is often co‐observed with thrombocytopenia 13,14 . Nevertheless, platelet count alone appears to be a poor predictor for IVH 14–17 .…”

“… 8 , 9 , 10 , 11 Thrombocytopenia affects up to 70% of preterm neonates with birthweight <1000 g, 12 and studies have found that IVH is often co‐observed with thrombocytopenia. 13 , 14 Nevertheless, platelet count alone appears to be a poor predictor for IVH. 14 , 15 , 16 , 17 Interestingly, it has been suggested that once the bleeding has occurred, a reduced platelet function in the preterm might contribute to expansion of the bleed.…”

“… 14 , 15 , 16 , 17 Interestingly, it has been suggested that once the bleeding has occurred, a reduced platelet function in the preterm might contribute to expansion of the bleed. 18 , 19 However, as reviewed by our group, platelet function in preterm neonates is only sparsely investigated 13 , 20 and its potential contribution to morbidity remains unclear.…”

Acquired Platelet Dysfunction—Laboratory and Clinical Implications

“…15 Grevsen et al present a systematic review and meta-analysis of the role of platelet counts and other platelet indices in premature neonates with intraventricular hemorrhage. 16 Moreover, current knowledge on the impact of secondary hemostasis and fibrinolysis is highlighted. One major finding presented by the authors is that neonates with platelet counts <100 Â 10 9 /L during the first week of life have an increased incidence of intraventricular hemorrhage.…”