(992) Low-Dose Versus High-Dose Fludrocortisone in Hyponatremia Associated With Subarachnoid Hemorrhage

Introduction: Fludrocortisone (FCT) may be used to prevent or correct hyponatremia in patients with aneurysmal subarachnoid hemorrhage (aSAH). Despite its frequent use, dosing strategies are highly variable. This study aimed to assess the efficacy and safety of high-dose FCT compared to low-dose FCT.

Methods: This retrospective cohort study included patients admitted to the Neurological Intensive Care Unit at Cleveland Clinic between August 2017 and August 2022. Adult patients with a diagnosis of aSAH were included if they were treated for cerebral salt wasting with FCT for at least 48 hours. Patients were excluded if they received FCT prior to admission or any diuretics within 24 hours prior to FCT initiation. The high-dose group received an average total daily dose of more than 0.3 mg, while the low-dose group received less than or equal to 0.3 mg.

Results: A total of 48 patients were included, with 24 patients in each group. The low-dose group had a significantly lower modified Fisher’s scale and baseline urine output compared to the high-dose group. After 48 hours, the low-dose group had a greater absolute change in serum sodium level compared to the high-dose group (2 mEq/L [IQR 0.5, 4.0] vs. 0 mEq/L [IQR -1.5, 2.5], p=0.04). After adjustment, low-dose FCT was associated with an increase of 2.8 mEq/L [95% CI, 0.4 - 5.2, p=0.02] in 48-hour sodium level compared to high-dose FCT. Additionally, patients in the low-dose group received a significantly lower amount of sodium and fluid supplementation. No difference was observed in dose escalation after 48 hours of therapy. No differences were found in normonatremia restoration after 48 hours and 72 hours and hypokalemia.

Conclusions: The low-dose FCT group demonstrated a slightly higher, but not clinically significant, increase in serum sodium when compared to the high-dose FCT group. Both groups achieved normonatremia, suggesting that either regimen could potentially be utilized for hyponatremia prevention. Larger prospective studies are necessary to determine the optimal dosing regimen of FCT, whether it is for prevention or correction of hyponatremia.