Introduction: Mineralocorticoids are often used to reduce natriuresis therefore decreasing sodium and fluid replacement in patients with aneurysmal subarachnoid hemorrhages. There is a lack of data for best dosing strategy in all neurologic emergencies. This study aims to evaluate the efficacy and compare different doses of fludrocortisone utilized for hyponatremia in all neurologic emergencies. Methods: This single-health system, retrospective, cohort study included adult patients admitted to a neurocritical care or neurosurgery unit who received high dose (> 0.3 mg/day, HD) or low dose (≤ 0.3 mg/day, LD) fludrocortisone for hyponatremia due to a neurologic emergency. The primary outcome was the change in sodium levels with LD versus HD fludrocortisone within 24 hours after reaching target dose. Secondary outcomes included fluid balance, hypokalemia, serum sodium levels, the dose and duration of other therapies targeting hyponatremia, hospital and ICU length of stay, and all-cause mortality. Results: 108 patients were included in analysis (LD n=51; HD n=57). There was no significant difference in the change in serum sodium levels (LD 4 mEq/L 1-6 vs HD 5 1.75-7 mEq/L; p=0.31). There was a significantly lower net fluid balance in the HD group 24 hours prior to target dose (LD 257 mL/day -668.7-679.9 vs HD -379.6 mL/day -895.7-229.5; p=0.03). Most patients required potassium replacement, with significantly higher doses in the HD group (80 mEq 20-120 vs 137 mEq 61-200; p=0.002). Duration of salt tablets (LD 8 days 4-11 vs HD 10 days 7-14; p=0.04) and sodium chloride infusions (LD 3 days 1-5 vs HD 6 days 2-10, p=0.005) were longer in the HD group. Dosing of salt tablets or sodium chloride infusions did not differ between therapies. A multivariate logistic regression for predictors of response to fludrocortisone showed that patients who received hypertonic saline (OR 2.84 1.01-7.97) or had a sodium level < 130 mEq prior to the maximum fludrocortisone dose (OR 6.54 1.64-26.1) were more likely to be responders. Conclusions: There was no significant difference in the change in serum sodium levels between patients that received LD and HD fludrocortisone for a neurologic emergency. More investigation is warranted into different dosing strategies of fludrocortisone for neurologic emergencies.
Ross et al. (Sun,) studied this question.