The utility of urine sodium-guided diuresis during acute decompensated heart failure

Abstract

Diuresis to achieve decongestion is a central aim of therapy in patients hospitalized for acute decompensated heart failure (ADHF). While multiple approaches have been tried to achieve adequate decongestion rapidly while minimizing adverse effects, no single diuretic strategy has shown superiority, and there is a paucity of data and guidelines to utilize in making these decisions. Observational cohort studies have shown associations between urine sodium excretion and outcomes after hospitalization for ADHF. Urine chemistries (urine sodium ± urine creatinine) may guide diuretic titration during ADHF, and multiple randomized clinical trials have been designed to compare a strategy of urine chemistry-guided diuresis to usual care. This review will summarize current literature for diuretic monitoring and titration strategies, outline evidence gaps, and describe the recently completed and ongoing clinical trials to address these gaps in patients with ADHF with a particular focus on the utility of urine sodium-guided strategies.

Keywords: Acute decompensated heart failure; Decongestion; Diuresis; Diuretic strategy; Natriuresis; Urine sodium.

Fig. 1

Evidence gaps, potential strategies, and ongoing clinical trials to determine optimal strategies for IV diuretic titration during acute decompensated heart failure hospitalizations. There remain many evidence gaps in determining optimal IV diuretic strategies during acute decompensated heart failure hospitalizations to relieve congestion. Several proposed strategies are outlined, with notation of the clinical trials that are currently underway to test these strategies. IV, intravenous; CDT, combination diuretic therapy; WRF, worsening renal function

Fig. 2

The urine sodium concentration (n=462) from urine samples collected immediately before the intravenous (IV) loop diuretic dose was administered in 285 patients with ADHF undergoing serial IV diuretic doses is presented as a histogram. These results suggest that 37% of patients would be categorized as diuretic “responders” prior to receiving an IV diuretic if a urine sodium concentration threshold of 70 mmol/L is used to identify responders. Data adapted from reference [60]

Fig. 3

Non-linear association between spot urine sodium concentration 2 hours after diuretic dosing and total urinary sodium excretion at 6 hours. At lower values, 2-h spot urine sodium may be linear with 6-h urine sodium excretion. At lower values of 2-h spot urine sodium the relationship with 6-h urinary sodium excretion may be linear. However, this relationship appears to not be linear at higher 2-h urinary sodium concentrations, thereby making it harder to predict natriuresis from urine sodium alone. Data adapted from reference [61]