Retrospective evaluation of risk factors for development of kidney injury after parenteral furosemide treatment of left‐sided congestive heart failure in dogs

BACKGROUND: Kidney injury (KI) has been documented in dogs treated with furosemide for left‐sided congestive heart failure (CHF). HYPOTHESIS/OBJECTIVES: Determine risk factors for development of KI in furosemide‐treated dogs and determine the effect of KI on survival. ANIMALS: Seventy‐nine client‐owned dogs receiving parenteral furosemide for CHF. METHODS: Serum creatinine (sCr) and electrolyte concentrations were determined during hospitalization and at first outpatient reevaluation to detect and stage KI (increase in sCr ≥0.3 mg/dL). Furosemide dosage administered between timepoints was calculated. Multivariable modeling was performed to identify predictors of KI and percent change in serum biochemistry results over time. RESULTS: Kidney injury was identified in 38/79 (48%) dogs and mostly occurred during hospitalization. Kidney injury was Grade I in 25 dogs, Grade II in 9 dogs, and Grade III in 4 dogs. Higher blood pressure was associated with acute KI during hospitalization (odds ratio, 1.03; 95% confidence interval [95% CI] 1.01‐1.07; P = .03) whereas PO furosemide dosage was associated with KI after hospital discharge (odds ratio, 7.77; 95% CI, 2.05‐68.6; P = .02). Baseline sCr and use of a furosemide continuous rate infusion were not associated with increased risk of KI. Kidney injury was not associated with long‐term outcome. Of 13 dogs with Grade II‐III KI, azotemia was reversible in 9 dogs, and 6 dogs survived >1 year after KI. CONCLUSIONS AND CLINICAL IMPORTANCE: In this cohort of dogs receiving parenteral furosemide for CHF, KI was common, mostly nonazotemic (Grade I), and did not impact survival.