Antibiotic dosing adjustments in hospitalized patients with chronic kidney disease: a retrospective chart review

Physiologically-based pharmacokinetic modeling for single and multiple dosing regimens of ceftriaxone in healthy and chronic kidney disease populations: a tool for model-informed precision dosing

Introduction: Ceftriaxone is one of commonly prescribed beta-lactam antibiotics with several label and off-label clinical indications. A high fraction of administered dose of ceftriaxone is excreted renally in an unchanged form, and it may accumulate significantly in patients with impaired renal functions, which may lead to toxicity. Methods: In this study, we employed a physiologically-based pharmacokinetic (PBPK) modeling, as a tool for precision dosing, to predict the biological exposure of ceftriaxone in a virtually-constructed healthy and chronic kidney disease patient populations, with subsequent dosing optimizations. We started developing the model by integrating the physicochemical properties of the drug with biological system information in a PBPK software platform. A PBPK model in an adult healthy population was developed and evaluated visually and numerically with respect to experimental pharmacokinetic data. The model performance was evaluated based on the fold error criteria of the predicted and reported values for different pharmacokinetic parameters. Then, the model was applied to predict drug exposure in CKD patient populations with various degrees of severity. Results: The developed PBPK model was able to precisely describe the pharmacokinetic behavior of ceftriaxone in adult healthy population and in mild, moderate, and severe CKD patient populations. Decreasing the dose by approximately 25% in mild and 50% in moderate to severe renal disease provided a comparable exposure to the healthy population. Based on the simulation of multiple dosing regimens in severe CKD population, it has been found that accumulation of 2 g every 24 h is lower than the accumulation of 1 g every 12 h dosing regimen. Discussion: In this study, the observed concentration time profiles and pharmacokinetic parameters for ceftriaxone were successfully reproduced by the developed PBPK model and it has been shown that PBPK modeling can be used as a tool for precision dosing to suggest treatment regimens in population with renal impairment.

Drug Utilization Evaluation and Impact of Pharmacist Interventions on Optimization of Piperacillin/Tazobactam Use: A Retrospective Analysis and Prospective Audit

(1) Background: Piperacillin/tazobactam is a broad-spectrum antimicrobial encompassing most Gram-positive and Gram-negative aerobic and anaerobic bacteria. The inappropriate use of such broad-spectrum antibiotics is an important contributor to the rising rates of antimicrobial drug resistance worldwide. Drug utilization evaluation studies and pharmacists' interventions are vital to assess, develop, and promote the rational use of antibiotics. This drug utilization study aimed to evaluate the current utilization practice of piperacillin/tazobactam in a hospital setting and assess the impact of pharmacist intervention in improving its appropriate use. (2) Methodology: In this study, we used a retrospective cohort and a prospective cohort, a cross-sectional, observational method. It included a retrospective (Cycle A/pre-intervention-CycA) phase followed by an educational interventional phase conducted by the pharmacists. During the 2 months of educational intervention, pharmacists used several methods, including workshops, lectures, oral presentations, and the development and reinforcement of clinical pathways to promote the judicious use of piperacillin/tazobactam. This was followed by a prospective (Cycle B/post-intervention-CycB) phase to improve piperacillin/tazobactam usage appropriateness. The appropriateness criteria for this drug utilization evaluation were established based on antimicrobial guidelines, the published literature, the institutional antibiogram, consultation from the antimicrobial stewardship committee, and the product monograph (Tazocin). The appropriateness of CycA and CycB patients was compared using the measurable elements, including indication and dose based on renal function, timely order for cultures, de-escalation, and use of extended infusion protocol. (3) Results: The study population comprised 100 patients in both CycA and CycB. The mean age of the patients was 66.28 ± 16.15 and 67.35 ± 17.98, and the ratios of men to women were found to be 49:51 and 61:39 in CycA and CycB, respectively. It was observed that inappropriate usage was high in CycA patients, and the appropriateness was improved in CycB patients. A total of 31% of inappropriate empirical broad-spectrum use was found in CycA, and it was reduced to 12% in CycB patients. The transition of appropriateness was observed in all measurable criteria, which includes the optimized dose according to the renal function (CycA = 49% to CycB = 94%), timely bacterial culture orders (CycA = 47% to CycB = 74%), prompt de-escalation (CycA = 31% to CycB = 53%), and adherence to extended infusion institutional guidelines (CycA = 34% to CycB = 86%). (4) Conclusions: The study highlighted important aspects of inappropriate piperacillin/tazobactam use. This can be considerably improved by proper education and timely interventions based on the pharmacists' vigilant approach. The study results emphasized the need for surveillance of piperacillin/tazobactam usage by conducting similar drug utilization evaluations and practice to improve quality and safety in healthcare organizations globally.

Antimicrobial Stewardship and Dose Adjustment of Restricted Antimicrobial Drugs in Hospital Setting

Antimicrobial consumption is increasing. In order to maximize the effectiveness of antimicrobial stewardship and provide safe and optimal use of restricted antimicrobial drugs, renal dosing should be evaluated. The aim of this study was to determine the prevalence of restricted antimicrobial drugs that required dose adjustment according to renal function. A retrospective, consecutive study was conducted at University Hospital Dubrava. This study analyzed requests for restricted antimicrobial drugs (n = 2890) during a 3-month period. Requests for antimicrobial agents were evaluated by the antimicrobial therapy management team (A-team). This study included 412 restricted antimicrobial drug requests requiring dose adjustment, of which 39.1% did not have an adjusted dose. Meropenem, Ciprofloxacin, Piperacillin/Tazobactam, Vancomycin, Colistin and the antimycotic Fluconazole were the most frequent restricted antimicrobial drugs that required dose adjustment according to impaired renal function. The results of this research highlight the importance of the A-team in the optimization of restricted antimicrobial therapy. Non-adjusted doses of restricted antimicrobial drugs increase the possibility of adverse drug reactions and therefore jeopardize pharmacotherapy outcomes and patient safety.

Antimicrobial Stewardship at Transitions of Care to Outpatient Settings: Synopsis and Strategies

Inappropriate antibiotic use and associated consequences, including pathogen resistance and Clostridioides difficile infection, continue to serve as significant threats in the United States, with increasing incidence in the community setting. While much attention has been granted towards antimicrobial stewardship in acute care settings, the transition to the outpatient setting represents a significant yet overlooked area to target optimized antimicrobial utilization. In this article, we highlight notable areas for improved practices and present an interventional approach to stewardship tactics with a framework of disease, drug, dose, and duration. In doing so, we review current evidence regarding stewardship strategies at transitional settings, including diagnostic guidance, technological clinical support, and behavioral and educational approaches for both providers and patients.

Pharmacist-driven renal dose optimization practice—outcomes of a retrospective study in ambulatory care settings

Objectives

Previous studies indicate a higher prevalence of inappropriate drug usage in patients with renal disease in ambulatory care settings and a higher rate of non-compliance with the renal dose adjustment protocol. This study aimed to investigate the number of renal dose adjustments recommended by pharmacists in ambulatory care settings, acceptance rate by the physicians and medications involved.

Methods

This two-year retrospective study was conducted in an ambulatory care pharmacy in a Saudi Arabian tertiary care hospital. Based on the renal protocol at the study site, the pharmacists recommended dose adjustments for inappropriate medication orders, and the outcomes were documented electronically. A quantitative descriptive analysis of this practice was performed by retrieving the pharmacists’ documentation from electronic health records. Only protocol-compliant recommendations with proper documentation were included in the study.

Key findings

A total of 302 renal dose adjustments were recommended by pharmacists for 269 patients involving 47 medications, with an average of 1.12 recommendations per patient. The average monthly recommendation was 12.58 (median: 11; SD: 5.174; 95% Confidence Interval (CI), 12 to 13.16). Of the 302 recommendations, 219 (72.52%) were accepted by the physician, and 71 (23.51%) were not. The most common medications accepted for renal dosage adjustment included levofloxacin (8.94%), metformin (5.29%), amoxicillin-clavulanate (5.29%), cetirizine (4.97%), diclofenac (4.64%), ciprofloxacin (3.97%) and nitrofurantoin (3.31%).

Conclusions

The pharmacist’s renal dose recommendations have a high acceptance rate in ambulatory care. This study demonstrated that ambulatory care pharmacists play a substantial clinical role in reducing inappropriate drug use in patients with renal disease.