Background: Clinical practice varies widely in the dosing and administration of loop diuretics for patients hospitalized with heart failure. Current guidelines are based primarily on expert opinion, although several small studies have suggested that continuous infusion is more effective than bolus administration in promoting diuresis and reducing the likelihood of renal dysfunction. Felker and colleagues conducted the Diuretic Optimization Strategies Evaluation trial to evaluate various diuretic strategies for acute decompensated heart failure.

The Study: The trial prospectively examined diuretic doses and administration modes in 308 patients requiring hospitalization for acute exacerbation of chronic heart failure, despite having been on an oral loop diuretic for at least one month. Patients were excluded if they required intravenous vasodilators or inotropic agents other than digoxin, had hypotension, or had a serum creatinine level greater than 3.0 mg per dL (265.2 μmol per L).

Patients were randomized to receive intravenous furosemide, which varied along two interventions: (1) low versus high dose (total daily dose either equivalent to or 2.5 times greater than the patient's previous daily loop diuretic dose, respectively); (2) and method of administration (continuous infusion versus boluses every 12 hours). The interventions were continued for up to 72 hours, with the treating physician having the option at 48 hours to adjust treatment if clinically warranted. Patients were monitored for 60 days after admission. The primary study outcomes included patients' global assessment of their symptoms, and changes in serum creatinine levels over the first 72 hours.

Results: Regardless of intervention, no differences were seen between the groups with regard to median hospital length of stay, 60-day mortality, rehospitalization, or emergency department visits. Similarly, there were no differences in patients' reported symptoms or in mean changes in creatinine level.

Patients receiving high-dose furosemide were more likely to be changed to oral diuretics at 48 hours than those assigned to the low-dose strategy (31 versus 17 percent; P < .001). They also had greater levels of fluid loss. High-dose furosemide was associated with a greater likelihood of a transient increase in serum creatinine of more than 0.3 mg per dL (26.52 μmol per L) during the initial 72 hours of treatment (23 versus 14 percent in the low-dose group; P = .04), which had resolved by day 60.

Conclusion: In patients with acute decompensated heart failure, there were no significant differences in patients' global assessment of symptoms or in the change in creatinine level from baseline to 72 hours when intravenous loop diuretics were given via bolus versus continuous infusion, or with a low-dose versus high-dose strategy.