Neonatal stroke refers to cerebrovascular events between 28 weeks of gestational age and 28 days postnatal and includes thromboembolic cerebral infarction and all kinds of intracranial haemorrhage.Neonatal stroke may contribute to severe neurological deficit, such as cerebral palsy and even death. International reports suggest the incidence to be approximately 1/4000 live births per year (1). There are several etiological hypothesises regarding risk factors, such as maternal, obstetrical and neonatal. Some maternal risk factors are thought to be of relevance, but conclusive results are yet to be revealed. In literature some authors hypothesisethat hypercoagulabilty of the maternofoetal circulation may predisposeneonatal stroke as well as placental injuries (2). Regarding obstetrical factors, vacuum delivery is associated with intracranial haemorrhage in neonates (3). Duration of labour and mode of delivery play an important role as well (4;5). Neonatal risk factors include embolic, thrombotic and ischemic events. Other possiblecauses are congenital heart disease (6;7), intravascular catheters (8), coagulation disorders (9;10), septicaemia and disseminated intravascular coagulopathy (11), asphyxia (12) and polycytemia (13).However, in more than a third of cases, no causes are found (14).Materials and Methods The survey was carried out as a retrospective data collection of the cases of neonatal stroke at Rikshospitalet during the period of 1993-2003. Study parameters were chosen based on scientific publications and clinical consensus on maternal, intrauterine, obstetrical and neonatal variables. All maternal and neonatal charts were analyzed on the selected parameters. Ideally, the study should have beendesigned having a control group, but for many reasons this would require more time than accessible for the purpose of this project. To learn more about the pathological mechanisms, we read literature (14) as well as recent studies found by searching Medline, some of which are referred to in the abstract.ResultsThe survey included 40 neonates and 40 mothers. Outcome data on cerebral events in neonates were 30 % cerebral infarction (12), and 70% cerebral haemorrhage, with differences in haemorrhages located in brain parenchyma 40% (16), sub-/epidural 20% (8) and subarachnoidal 10% (4). Seizures (35%) and irritability (35%) were the two major debut symptoms in neonates with infarction or cerebral haemorrhage. Only one child did not have any symptoms at all. Time to onset and diagnosis was approximately 20 hours. Many of the revised parameters, such as coagulation disorders, operative delivery and intravascular catheters showed similarities to published data. One German study of 91 neonates with ischemic events showed an OR of 6,70 for at least one prothrombotic risk factor compared to the control group (9). Data from our survey, showed that four children with cerebral infarction that also were tested for coagulation disorders had at leastone prothrombotic risk factor. Furthermore, our data showed a high number of operative deliveries (60 %), also being consistent with international literature (3;5). Finally, 22,5 % of the neonates in our survey had intravasal catheters for replacement therapy and monitoring. Indeed, this finding is interesting due to data ininternational studies (8;13) indicating the combination of intravasal catheters and familial thrombophilia to play an important role in thromboembolism in children (15).DiscussionThe etiology of neonatal stroke has multiple causes. Knowledge on maternal, obstetric and neonatal risk factors is of major importance for providing prophylactic interventions as well as improving treatment both for obstetrical and neonatal care. We hope that this study may contribute to an increased awareness of neonatal stroke, thus apply a standardized evaluation of possible thrombotic disease in all cases of ischemic stroke in infants. Its causes and risk factors need further investigations.
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