Association between diuretics and successful discontinuation of continuous renal replacement therapy in critically ill patients with acute kidney injury

Abstract

Background: Despite aggressive application of continuous renal replacement therapy (CRRT) in critically ill patients with acute kidney injury (AKI), there is no consensus on diuretic therapy when discontinuation of CRRT is attempted. The effect of diuretics on discontinuation of CRRT in critically ill patients was evaluated.

Methods: This retrospective cohort study enrolled 1176 adult patients who survived for more than 3 days after discontinuing CRRT between 2009 and 2014. Patients were categorized depending on the re-initiation of renal replacement therapy within 3 days after discontinuing CRRT or use of diuretics. Changes in urine output (UO) and renal function after discontinuing CRRT were outcomes. Predictive factors for successful discontinuation of CRRT were also analyzed.

Results: The CRRT discontinuation group had a shorter duration of CRRT, more frequent use of diuretics after discontinuing CRRT, and greater UO on the day before CRRT discontinuation [day minus 1 (day - 1)]. The diuretics group had greater increases in UO and serum creatinine elevation after discontinuing CRRT. In the CRRT discontinuation group, continuous infusion of furosemide tended to increase UO more effectively. Multivariable regression analysis identified high day - 1 UO and use of diuretics as significant predictors of successful discontinuation of CRRT. Day - 1 UO of 125 mL/day was the cutoff value for predicting successful discontinuation of CRRT in oliguric patients treated with diuretics following CRRT.

Conclusions: Day - 1 UO and aggressive diuretic therapy were associated with successful CRRT discontinuation. Diuretic therapy may be helpful when attempting CRRT discontinuation in critically ill patients with AKI, by inducing a favorable fluid balance, especially in oliguric patients.

Keywords: Acute kidney injury; Continuous renal replacement therapy; Diuretics.

Fig. 1

Study design. From September 2009 to December 2014, 2225 ICU patients treated with continuous renal replacement therapy (CRRT) in whom CRRT discontinuation was attempted were screened. A total of 1176 patients were included and classified into three groups based on discontinuation of CRRT. Patients were further divided into control or diuretics groups depending on administration of diuretics after discontinuation of CRRT. The control group included patients who were not treated with diuretics. AKI, acute kidney injury; HD, hemodialysis; ICU, intensive care unit

Fig. 2

Changes in urine output and renal function after discontinuation of continuous renal replacement therapy (CRRT). a Overall changes in urine output. The urine output of the CRRT discontinuation group was significantly increased compared with that of other groups after stopping CRRT. b Overall changes in serum creatinine. The hemodialysis (HD) initiation group had significantly elevated serum creatinine compared with other groups. c Changes in urine output between the control and the diuretics subgroups in the CRRT discontinuation group. The diuretics subgroup had a significant increment in urine output. d Changes in serum creatinine between the control and the diuretics subgroups in the CRRT discontinuation group. The diuretics subgroup had significantly elevated serum creatinine. e Changes in urine output depending on method of administration of diuretics. The CIV group showed a tendency to increase urine output more effectively compared to other methods of delivery. f Changes in serum creatinine depending on the administration method of diuretics. The continuous intravenous infusion of furosemide (CIV) group had significantly elevated serum creatinine. INT, intermittent intravenous infusion of furosemide; PO, furosemide administration per oral or Levin tube; D, day

Fig. 3

Predictive ability of urine output one day before continuous renal replacement therapy (CRRT) discontinuation [day minus 1 (day − 1)] for discontinuation of CRRT in the diuretics group. a Receiver operating characteristic (ROC) analysis of the day − 1 urine output for prediction of successful discontinuation of CRRT. Optimal cutoff value of the day − 1 urine output in all patients was 191 mL/day. The area under the ROC curve was 0.821 (95% CI 0.797–0.845, p < 0.001), sensitivity was 81.2% (95% CI 77.6–84.5%), and specificity was 71.6% (95% CI 68.0–75.0%). b ROC analysis of the day − 1 urine output for predicting successful discontinuation of CRRT in oliguric (urine output ≤ 400 mL/day) patients in the diuretics group. Optimal cutoff value of the day − 1 urine output was 125 mL/day. The area under the ROC curve was 0.745 (95% CI 0.692–0.798, p < 0.001), sensitivity was 72.1% (95% CI 64.6–78.8%), and specificity was 68.8% (95% CI 61.3–75.7%)