Give a Little, Get a Lot: The Power of IV Fluids in Heart Failure

Introduction Intravenous (IV) loop diuretics are the mainstay for treatment of acute decompensated heart failure (ADHF). Activation of the renin-angiotensin system with diuresis can result in intravascular volume depletion despite total volume overload. Diuretic resistance and acute kidney injury can quickly ensue. Hypothesis Based on RenalGuard device data, we hypothesized that co-administration of IV fluids (IVF) and diuretics will maintain plasma filling, resulting in preserved renal function and more effective diuresis. Feasibility of carrying out these actions manually throughout the 24-hour period was also assessed. Methods Four patients (pts) admitted with ADHF refractory to IV diuretics were identified and received furosemide infusion. Fluid loss limit (FLL) was assessed hourly and replacement IVF was given to replace excess fluid removed or to meet the FLL. After 24 hours, IVF repletion was stopped. Hemodynamics, urine output, fluid intake, renal function, and plasma/urine electrolytes were monitored. Results With co-administration of IVF and diuretics, pts achieved a greater net fluid loss during the treatment period. Average (avg) net fluid loss for the 4 pts was 512 mL greater during the 24h treatment period compared to the 24h prior to treatment. Renal function improved in all 4 pts. After 24 hrs of treatment, avg creatinine change was -0.3 mg/dL, avg BUN change was -5 mg/dL, and avg eGFR increase was 7.3 mL/min. After IVF were discontinued, renal function declined. On physical exam, all 4 pts showed improvement in JVD, and lower extremity edema became less tense. In the setting of hourly adjustments of IVF/diuretics and monitoring of hemodynamics/labs, a 1:1 nurse to patient ratio was required for the duration of the treatment period in addition to hourly evaluations by advanced practitioners. Conclusions This small feasibility study showed that simultaneous administration of IVF with diuretics to maintain intravascular volume protects and may improve kidney function as well as improve patient symptoms with more effective diuresis and decongestion. Though an effective way to diurese patients, manual titration of IVF/diuretics was tedious, time consuming, and required significant manpower, including physicians and nurses for hourly patient clinical assessments and determination of FLL. This therapy was effective but would benefit from automation of the delivery system due to the workload burden on healthcare providers. The REPRIEVE study utilizing the Reprieve system to guide diuretic therapy with co-administration of IVF will test this hypothesis further.