Performance characteristics of a sliding-scale hypertonic saline infusion protocol for the treatment of acute neurologic hyponatremia.

background and purposeHypertonic saline (3% NaCl) infusions can be used to treat acute neurologic hyponatremia (ANH) in critically ill patients with neurological and neurosurgical disorders such as subarachnoid hemorrhage. Adjustments in the rate of hypertonic saline infusions to treat ANH are needed to achieve a goal sodium range and are usually made on an empiric basis. To date, no data are available to determine how reliably such adjustments achieve stable, normal serum sodium concentrations or how often iatrogenic hypernatremia occurs during the course of treatment with hypertonic saline.

methodsWe have instituted a standardized sliding-scale hypertonic saline protocol to minimize patient-to-patient variability of hypertonic saline administration and to attempt to achieve safe rates of sodium correction and stable maintenance of serum sodium concentration with minimal overshoot. Here, we present a retrospective analysis of the performance characteristics of our standardized hypertonic saline protocol over a 1-year period, in 49 patients.

resultsThe mean rate of initial sodium correction was 0.44 +/- 0.36 (mEq/l)/h. During the maintenance infusion phase, 84.3 +/- 17.8% of the time was spent in goal range (Na 136-145 mEq/l), 14.9 +/- 18.1% of the time was spent in mild undershoot (Na 130-135 mEq/l), and 0.7 +/- 3.1% of the time was spent in overshoot (Na >145 mEq/l). No adverse events attributable to infusion of hypertonic saline were encountered.

conclusionOur hypertonic saline sliding-scale protocol for treatment of ANH can be used reliably and achieves normal sodium concentrations in a safe manner with minimal overshoot.