Scientific Poster Session IV - Original Research

Original Research
  Tuesday, November 14, 2023
  08:30 AM–10:00 AM

Abstract

Introduction: Guidelines recommend IV loop diuretics for patients hospitalized with acute heart failure (AHF) and volume overload; additional agents can be added as needed. However, limited data guide which augmenting agent to add.

Research Question or Hypothesis: Do chlorothiazide (CTZ) and metolazone (MTZ) differ in efficacy or safety when used in combination with loop diuretics for diuresis in diuretic-resistant patients with AHF and impaired renal function?

Study Design: Multi-center, retrospective study analyzing 6 months of data from patients with hospitalized AHF who received MTZ or CTZ in addition to IV loop diuretics.

Methods: Adult patients with an estimated glomerular filtration (eGFR) <45 mL/min/m2 who received at least 80mg IV furosemide equivalents for at least 24 hours prior to thiazide administration were included. Patients who were prisoners, pregnant, CrCl <10 mL/min, or on multiple thiazide diuretics within the study period were excluded. The primary endpoint was a comparison of 24-hour urine output (UOP) between the 24 hours before and after thiazide administration. Secondary and safety endpoints included weight change, requirement for vasopressors or inotropes during the study period, electrolyte abnormalities, and changes in eGFR.

Results: A total of 223 patients were included. Baseline demographics were similar between groups except for age (higher in MTZ) and home loop diuretic dose (higher in CTZ). Mean 24-hour UOP increased more among CTZ patients (1668 to 3826 mL) versus MTZ (1672 to 2834 mL) (p<0.001). No differences in weight, eGFR, or SCr were observed. CTZ patients were more likely to require norepinephrine, vasopressin, or dobutamine (p<0.05) but not other vasopressors or inotropes. More hypomagnesemia was observed in the MTZ group; no differences in other electrolytes were observed.

Conclusion: CTZ was associated with a greater increase in 24-hour UOP than MTZ. CTZ-treated patients were more likely to require vasopressors/inotropes but less likely to experience electrolyte abnormalities.

Presenting Author

Caitlin Gibson PharmD, MEd, BCPS, BCCP
Virginia Commonwealth University School of Pharmacy

Authors

Meghan Beard PharmD, BCPS
VCU Health

Brittany Good PharmD, BCPS
Inova Fairfax Medical Campus

Alisa Escano PharmD, BCPS
Albert Truong PharmD Candidate
VCU School of Pharmacy

Benjamin Van Tassell PharmD
VCU School of Pharmacy