Treating intracranial hypertension: time to abandon mannitol?

In response to this uncertainty and the evidence suggesting that mannitol and hypertonic saline have equivalent initial effects on intracranial hypertension, the two fluids are probably used almost interchangeably in current Australian and New Zealand critical care practice in patients with refractory intracranial hypertension. However, mannitol has the potential disadvantages of rebound intracranial hypertension and intravascular dehydration. In contrast, hypertonic saline restores intravascular volume, may better maintain central perfusion, and is not associated with any rebound effects. Therefore, despite historical preferences, there is a better rationale for use of hypertonic saline than there is for mannitol. What should we do? We believe the answer lies not in more random practice, but in more research. This is an important area of ICU research that needs to be tackled with properly designed double-blind randomised controlled trials, first aimed at ICP management and then at changing clinical outcomes. If using saline instead of albumin resuscitation can change outcome in patients with traumatic brain injury, it is conceivable that choosing the correct osmotherapy agent could do the same. We need to find out.