Evaluation of traditional initial vancomycin dosing versus utilizing an electronic AUC/MIC dosing program

Risk of Acute Kidney Injury Based on Vancomycin Target Trough Attainment Strategy: Area-Under-the-Curve-Guided Bayesian Software, Nomogram, or Trough-Guided Dosing

BACKGROUND

Guidelines support area-under-the-curve (AUC) monitoring for vancomycin dosing which may lower overall doses and reduce acute kidney injury (AKI).

OBJECTIVE

The aim of this study was to compare incidence of AKI across 3 vancomycin dosing modalities: AUC-targeted Bayesian pharmacokinetic software, AUC-targeted empiric dosing nomogram, and trough-guided dosing using clinical pharmacists' judgment.

METHODS

This retrospective study included adult patients with a pharmacy dosing consult who received ≥1 dose of vancomycin and ≥1 serum vancomycin level documented between January 1, 2018, and December 31, 2019. Patients with baseline serum creatinine ≥2 mg/dL, weight ≥100 kg, receiving renal replacement therapy, AKI prior to vancomycin therapy, or vancomycin ordered only for surgical prophylaxis were excluded. The primary analysis was incidence of AKI adjusted for baseline serum creatinine, age, and intensive care unit admission. A secondary outcome was adjusted incidence of an abnormal trough value (<10 or >20 μg/mL).

RESULTS

The study included 3459 encounters. Incidence of AKI was 21% for Bayesian software (n = 659), 22% for the nomogram (n = 303), and 32% for trough-guided dosing (n = 2497). Compared with trough-guided dosing, incidence of AKI was lower in the Bayesian (adjusted odds ratio [OR] = 0.72, 95% confidence interval [CI]: 0.58-0.89) and the nomogram (adjusted OR = 0.71, 95% CI: 0.53-0.95) groups. Compared with trough-guided dosing, abnormal trough values were less common in the Bayesian group (adjusted OR = 0.83, 95% CI: 0.69-0.98).

CONCLUSION AND RELEVANCE

Study results suggest that use of AUC-guided Bayesian software reduces the incidence of AKI and abnormal trough values compared with trough-guided dosing.

Comparison of Adverse Events With Vancomycin Diluted in Normal Saline vs Dextrose 5

Background

IV vancomycin is widely used for infections caused by Gram-positive bacteria; however, nephrotoxicity is commonly associated with its use. Clinical trials have shown an increased incidence of acute kidney injury (AKI) using normal saline (NS) for fluid resuscitation. This study evaluated differences in AKI and other patient outcomes associated with vancomycin diluted in NS compared with dextrose 5% in water (D5W).

Methods

This retrospective cohort study conducted at a single US Department of Veterans Affairs hospital included veterans who received vancomycin for at least 48 hours between July 1, 2015 and June 30, 2020. This study compared adverse events (AEs) of patients receiving vancomycin diluted in either NS or D5W. The primary outcome was incidence of AKI. Secondary outcomes included incidence of hyperglycemia, hyperchloremia, hypernatremia, metabolic acidosis, in-hospital mortality, and 30-day posthospitalization mortality.

Results

The study included 123 patients in each group (N = 246). The percentage of AKI was 22.8% in the D5W group compared with 14.6% the NS group (P = .14). There were no significant differences in the rates of hyperglycemia, hyperchloremia, hypernatremia, or metabolic acidosis between the 2 groups. In-hospital mortality and 30-day posthospitalization mortality were similar between the groups.

Conclusions

This study comparing the AEs of IV vancomycin diluted in NS and D5W found no significant differences in AKI or other patient outcomes. These study results do not suggest the crystalloid used to dilute IV vancomycin is associated with differences in nephrotoxicity or other relevant AEs.