Impact of continuous vs. intermittent vancomycin treatment on kidney function of critically ill patients

Background: Nephrotoxicity is one of the most relevant side-effects of vancomycin. So far, continuous vancomycin treatment (CVT) in critically ill patients has not been shown to be superior to its intermittent administration (IVT) regarding the development of an acute kidney injury (AKI). With this retrospective analysis, we aimed to determine the incidence of an AKI under IVT and CVT and tried to identify predictors by applying regression analysis. Patients and methods: After ethics approval we analysed data from 578 patients treated on the operative and medical intensive care unit (ICU) of the Medical Center Cologne-Merheim (between 2012 - 2019) without renal replacement therapy on ICU admission. We compared the intervention groups IVT (n = 147, median age 67 years, 28.6 % female) and CVT (n = 119, median age 59 years, 39.5 % female) with a control-group without vancomycin treatment (CON, n = 312, median age 70 years, 39.4 % female). Severity of renal injury was assessed using AKIN criteria. For statistical analysis Chi(2-), Kruskal-Wallis test, correlation analysis and a logistic regression was performed, considering a p < 0.05 as significant. A Bonferroni-corrected a is marked as alpha'. Results: Serum-creatinine at begin of treatment (0.92 vs. 0.91 mg / dl; p = 0.9775, alpha' = 0.0019) was comparable between patients with or without vancomycin treatment. AKI was comparably frequent in the IVT-group and the CVTgroup (34.7 vs. 20.2 %; p = 0.0089; alpha' = 0.0019). Patients with vancomycin-associated AKI required more often inotropic therapy (p = 0.00; alpha = 0.01). The mortality of these pa-tients was significantly higher (48.0 vs. 16.8 %; p = 0.00; alpha' = 0.01). Conclusions: Continuous vancomycin treatment was not superior to intermittent administration regarding the development of AKI. Larger, prospective and randomised clinical trials are necessary to assess the potential benefits of a continuous infusion regimen.