A Pilot Study of Target Weight Guided Treatment in Acute Heart Failure Using Ultrafiltration or Usual Care: Effect on Sodium Removal

Background and Objectives: In the Ultrafiltration versus Intravenous Diuretics for Patients Hospitalized for Acute Decompensated Heart Failure trial, ultrafiltration (UF) removed volume more effectively than usual care (UC). Hypothetically, UF may be superior to UC due to increased sodium (Na) removal and less neurohormonal activation. We compared UF and UC in a randomized pilot trial of target weight guided therapy for acute decompensated heart failure (ADHF). Subjects and Methods: Sixteen patients with ADHF were enrolled and target weights established prospectively, prior to randomization to UC or UF. UF patients did not receive diuretics and UC patients were all treated with a continuous furosemide drip. All urine and ultrafiltrate were collected and Na concentrations measured. Results: Similar volumes were removed in UC and UF groups (110105 mL and 107415 mL, respectively) and the UF group also produced 45325 mL of urine. Na concentration was $138{\pm}6meq/L$ in the ultrafiltrate, $85{\pm}73meq/L$ in the UC group's urine, and $26{\pm}23meq/L$ in the UF group's urine. Given the relevant associated volumes, total meq of the Na removed was similar (1168 in UC vs. 1216 in UF). The UF group produced isotonic ultrafiltrate and a higher volume of dilute urine than anticipated. Conclusion: In a randomized pilot study of target weight guided therapy with UC or UF for ADHF, there were no differences in total volumes or Na removed, and lengths of hospital stays were similar. Isotonic fluid loss by UF was accompanied by the production of very dilute urine.