P3534Optimal dosing of initial bolus of intravenous furosemide in acute heart failure: insights from REALITY-AHF

Abstract

Abstract Background Although intravenous diuretics are a cornerstone in the treatment of patients with acute heart failure (AHF), optimal dosing of initial bolus of IV diuretics has not been well elucidated. Methods The initial IV bolus dose of furosemide and its association with outcomes were analyzed in 1290 AHF patients (median age, 81 years, 55% were male) derived from REALITY-AHF (Registry Focused on Very Early Presentation and Treatment in Emergency Department of Acute Heart Failure). The patients were divided into 3 groups; lower dose (lower than recommended dose, n=371), standard dose (same as recommended dose, n=807), and higher dose (higher than recommended dose, n=112) groups according to the recommended initial IV bolus furosemide dose derived from the maintenance loop diuretics dose (for those without taking oral loop diuretics or taking ≤40mg/day oral furosemide-equivalent loop diuretics, 20mg IV bolus furosemide; those on >40mg/day oral furosemide-equivalent loop diuretics, IV bolus furosemide at the same dose as oral loop diuretic dose). Outcomes were length of hospital stay, diuretic response (urine output achieved within 48 hours of admission per 40 mg furosemide-equivalent diuretics dose), and 60-day all-cause mortality. Results Median amount of first IV bolus furosemide dose were 10, 20, and 40 mg for lower, standard, and higher dose groups, respectively. After adjustment for other covariates, length of hospital stay was significantly longer by 2.6 days (p=0.018) in the lower dose group compared to the standard dose group, and there was no difference between the standard and high dose groups (p=0.221). Diuretic response within 48 hours of admission was significantly better in the lower dose group (beta coefficient: 244 mL, p=0.025) and significantly worse in the higher dose group (beta coefficient: - 1098 mL, p<0.001) compared to the standard dose group after adjustment for covariates. During 60 days of admission, 91 deaths were observed, and 60-day mortality was significantly higher in the higher dose group (HR: 2.80, 95% CI: 1.49–5.26, p=0.001), but not in the lower dose group (HR: 1.18, 95% CI: 0.67–2.08, p=0.571) compared to the standard dose group after adjustment for other prognostic factors. Conclusion Treatment with the recommended initial bolus of IV furosemide is associated with a shorter hospital stay compared to lower dose regimen and better diuretic response and better 60-day survival compared to higher dose regimen in patients with AHF. Acknowledgement/Funding This study was funded by The Cardiovascular Research Fund, Tokyo, Japan.