Management of Raised Intracranial Pressure
The trend in the field of neurological critical care, according to recent surveys, has been to use saline in preference to mannitol. The reasons for this preference are, in my opinion, not entirely clear and may be overstated. Although a few randomised trials have been conducted comparing the two agents, some purportedly provide evidence favouring hypertonic saline, but it is not difficult to find the flaws in the design and implementation of these studies. Meta-analyses have further favoured hypertonic saline depending on the models used, some of which are contrived. Several recent articles also express the strong opinion that hypertonic saline, not mannitol, is a better choice and is the 'gold standard'. A summary of the trials and a perspective on hyperosmolar treatment can be found in the article by Hinson et al.
Curiously, mannitol has been endorsed in society guidelines to treat adults with intracranial hypertension and hypertonic saline, to treat children. In the elderly or in patients with diabetes, I use hypertonic saline to avoid severe dehydration, whereas, in patients with congestive heart failure, I use mannitol to avoid a sudden intravascular fluid overload from saline. Neither one of these suggestions is absolute, as both agents can cause severe hyperosmolarity and fluid overload.
Comparisons Between Mannitol and Hypertonic Saline
The trend in the field of neurological critical care, according to recent surveys, has been to use saline in preference to mannitol. The reasons for this preference are, in my opinion, not entirely clear and may be overstated. Although a few randomised trials have been conducted comparing the two agents, some purportedly provide evidence favouring hypertonic saline, but it is not difficult to find the flaws in the design and implementation of these studies. Meta-analyses have further favoured hypertonic saline depending on the models used, some of which are contrived. Several recent articles also express the strong opinion that hypertonic saline, not mannitol, is a better choice and is the 'gold standard'. A summary of the trials and a perspective on hyperosmolar treatment can be found in the article by Hinson et al.
Curiously, mannitol has been endorsed in society guidelines to treat adults with intracranial hypertension and hypertonic saline, to treat children. In the elderly or in patients with diabetes, I use hypertonic saline to avoid severe dehydration, whereas, in patients with congestive heart failure, I use mannitol to avoid a sudden intravascular fluid overload from saline. Neither one of these suggestions is absolute, as both agents can cause severe hyperosmolarity and fluid overload.