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

Effects of inpatient creatinine testing frequency on acute kidney injury identification and staging: a historical cohort study

BACKGROUND

Acute kidney injury (AKI) is a multifactorial condition often induced by drugs commonly used in hospitals. Identifying and staging AKI necessitates frequent monitoring of renal function.

AIM

To assess the impact of real-world hospital practices regarding serum creatinine (SCr) testing on the identification and staging of AKI, and its implications for adjusting drug doses.

METHOD

A historical cohort study utilizing hospital records from all adult patients admitted between 01/06/2018 and 31/12/2020 was conducted. Patients with no SCr assessment during their stay or those with an SCr at admission ≥ 2 mg/dL were excluded. AKI was determined using two criteria, namely AKIN and KDIGO, considering the time intervals between two SCr tests as outlined in the criteria. Additionally, patients with SCr increases exceeding AKI limits, regardless the time interval, were also identified. The estimated glomerular filtration rate (eGFR) and kinetic eGFR (KeGFR) were calculated.

RESULTS

During the study period, 17,269 hospitalizations and 62,255 SCr tests were recorded. Among the 17,032 hospitalizations with a length of stay > 48 h, 46.8% experienced periods with no SCr tests performed for more than 48 h. Any stage of AKI was identified in 7.0% of patients and in 9.1% using AKI and KDIGO criteria, respectively. Ignoring time limits in both criteria revealed potential AKI in 1942 patients (11.2%), indicating a potential underdiagnosis of AKI by 37.5% or 19.1%, depending on the criteria used. A total of 76 drugs requiring dose adjustment in patients with eGFR ≤ 50 ml/min were prescribed in 78.5% admissions. These drugs were prescribed in 87.9% of patients potentially underdiagnosed with AKIN and in 88.9% with KDIGO.

CONCLUSION

There is a need for changes in the established hospital procedures to ensure more frequent testing of SCr levels. Implementing an advanced scope of practice for clinical pharmacists could support these changes.

Acute Kidney Injury Incidence With Bayesian Dosing Software Versus 2-Level First-Order Area Under the Curve-Based Dosing of Vancomycin With Piperacillin-Tazobactam

Background: Two methods of area under the curve (AUC) dosing are recommended in vancomycin consensus guidelines: first-order calculations utilizing 2 vancomycin concentrations or a Bayesian approach. It is unknown if there is a difference in acute kidney injury (AKI) between the 2 dosing strategies for patients receiving concomitant piperacillin-tazobactam and vancomycin (VPT). Objective: The objective of this study was to compare incidence of AKI in patients being administered VPT with first-order calculations versus model-informed precision dosing (MIPD)/Bayesian dosing. Methods: This was a single-center, retrospective, observational study at a community hospital. Patients who received VPT therapy for at least 48 hours were included. The primary outcome was overall incidence of AKI. Secondary outcomes included percentage target attainment with initial regimen, average serum creatinine increase, time to AKI, usable vancomycin levels, and need for temporary dialysis or intensive care unit admission. Results: There were 100 patients included (50 in the first-order group and 50 in the MIPD/Bayesian group). The overall incidence of AKI was lower in the MIPD/Bayesian group (12% vs 28%, P = 0.046). There was no difference in average serum creatinine increase, time to AKI, need for temporary dialysis, or intensive care unit admission. Patients in the MIPD/Bayesian group had a higher percentage of target attainment (46% vs 18%, P = 0.003) and usable vancomycin levels (98% vs 60%, P < 0.001). Conclusion and Relevance: In patients receiving VPT, model-informed precision dosing with Bayesian modeling resulted in a lower rate of AKI, higher target attainment, and more usable vancomycin levels compared with first-order AUC dosing. The small sample and retrospective nature of this study reinforces the need for additional data.