In patients with the syndrome of inappropriate antidiuresis (SIAD), furosemide with or without sodium chloride combined with ﬂuid restriction does not improve correction of hyponatremia compared with ﬂuid restriction alone, investigators concluded.
In addition, patients receiving furosemide had increased incidences of acute kidney injury (AKI) and hypokalemia.
In an open-label study, investigators at Chiang Mai University in Chiang Mai, Thailand, recruited 92 patients with serum sodium concentrations of 130 mmol/L or less due to SIAD and randomly assigned them 1 of 3 groups: fluid restriction alone (31 patients), fluid restriction and furosemide (30 patients), or fluid restriction, furosemide, and sodium chloride (31 patients). Strictness of fluid restriction (less than 1000 or less than 500 mL/day) was guided by urine to serum electrolyte ratio. Furosemide dosage was 20 to 40 mg/day. Sodium chloride supplements were 3 g/day. All treatments were continued for 28 days. The primary outcome was change in sodium concentration at days 4, 7, 14, and 28 after randomization.
The study population had a mean baseline sodium concentration of 125 mmol/L, with no significant differences among the groups, Kajohnsak Noppakun, MD, and colleagues reported in the American Journal of Kidney Diseases. The study also found no significant differences among the 3 groups with regard to changes in sodium concentration and the percentage of patients and time to reach a sodium level of 130 mmol/L or higher or 135 mmol/L or higher.
AKI and hypokalemia (potassium level 3.0 mmol/L or less) occurred more frequently among patients receiving furosemide. The proportion of patients who experienced AKI was 10% in the fluid-restriction-only group compared with 17% of patients treated with furosemide and fluid restriction and 32% of those treated with furosemide, sodium chloride, and fluid restriction.
Significant hypokalemia (serum potassium levels 3.0 mmol/L or less) developed in 13% of the fluid-restriction-only group compared with 23% and 42% of patients treated with furosemide and fluid restriction and those treated with the triple regimen, respectively.
Krisanapan P, Vongsanim S, Pin-on P, et al. Efficacy of furosemide, oral sodium chloride, and fluid restriction for treatment of syndrome inappropriate antidiuresis (SIAD): An open-label randomized controlled study (the EFFUSE-FLUID trial). Am J Kidney Dis. doi: 10.1053/j.ajkd.2019.11.012