Medical management of raised intracranial pressure after severe birth asphyxia

The effects of dexamethasone and 20% mannitol infusion in reducing raised intracranial pressure were assessed in severely asphyxiated newborn infants. Intracranial pressure was measured continuously by a percutaneously placed subarachnoid catheter, and cerebral perfusion pressure was calculated from this and blood pressure data. Dexamethasone treatment, assessed in seven infants, produced an overall fall in intracranial pressure which was sustained for at least six hours, but this was coincident with a simultaneous reduction in systemic blood pressure with no change in the cerebral perfusion pressure. Mannitol, studied on nine occasions, produced a fall in intracranial pressure in each case, together with an overall rise in cerebral perfusion pressure 60 minutes after starting the infusion; this was sustained for a further four hours. We can find little to support the routine use of dexamethasone in severe perinatal asphyxia but mannitol infusion seems of value in treating raised intracranial pressure associated with cerebral oedema.