Earlier Targeted Vancomycin Troughs Concentration with Loading Dose: A Retrospective Study

Abstract Background: Studies have shown the failure of vancomycin treatment against vancomycin-sensitive gram-positive bacteria is common, possibly because the drug concentration did not reach the target serum concentration in time. In this study, we conducted a retrospective analysis to determine whether the target serum concentration could be reached earlier with the first loading dose of vancomycin.Methods: A retrospective single-center study was conducted in the Department of Critical Care Medicine, Ruijin Hospital North Affiliated to Shanghai Jiao Tong University School of Medicine between June 2018 and June 2020. The study enrolled patients who were suspected or confirmed with gram-positive bacterial infection and had been treated with vancomycin. According to whether the first loading dose of vancomycin was given, the patients were divided into the loading dose and the control groups. The serum concentration of vancomycin before the second dose and that before the fifth dose were compared to determine whether the target serum concentration was reached earlier with the first loading dose. And renal functions were monitored for a week to analyze whether the loading dose caused any acute kidney injury.Results: 55 patients were finally included in the study. Of these patients, 29 received first-loading dose of vancomycin, while the remaining 26 patients underwent the traditional dose regimen of vancomycin. The concentration of vancomycin before the second dose was 10.3±6.1 mg/L in the loading group, and 5.7±4.4 mg/L in the control group, significantly higher in the former group (P=0.002). The concentration of vancomycin before the fifth dose was 12.4±7.3 mg/L in the loading group, and 10.3±6.3 mg/L in the control group, where there was no inter-group difference (P=0.251). The 28-day motality of loading dose group is significantly lower (6.7% vs 34%, P=0.026) than the control group. There were no significant changes in serum creatinine levels in both groups, and there was no statistical difference in serum creatinine levels between the two groups.Conclusions: With the loading dose of vancomycin, the target serum concentration of vancomycin could be reached earlier without causing acute kidney injuries, also the mortality might be reduced.