Assessment of the Workflow and Time to Antibiotic Dose Adjustment for Critically Ill Patients Starting Continuous Renal Replacement Therapy

Background: Acute kidney injury (AKI) remains a common sequela of sepsis necessitating use of continuous renal replacement therapy (CRRT). In the setting of AKI, renally adjusted antimicrobials (eg, beta-lactams) are dose reduced to prevent toxicity; however, the extracorporeal clearance of CRRT may lead to subtherapeutic exposures of dose reduced antimicrobials. The present study sought to evaluate the time to dose adjustment to CRRT appropriate doses of antimicrobials after initiation of CRRT. Methods: A retrospective cohort study of patients on CRRT and anti-pseudomonal beta-lactams was conducted. CRRT was conducted as continuous veno-venous hemodialysis (CVVHD) per institutional standards. Baseline characteristics were collected including dialysate flow rate. The primary outcome was time to CRRT appropriate dose adjustment. Secondary outcomes included the pharmacist shift (ie, day, evening, or night shift) that CRRT was ordered and initiated. Continuous data were reported as median (IQR). Results: Forty-four patients were included in the analysis. The median dialysate flow rate was 2.3 L/hour (2, 3.1). Of included patients, 75% received cefepime therapy while 25% received meropenem. The median time to CRRT appropriate dosing was 13 hours (6, 20). CRRT was most commonly ordered during day shift (68%) but not started until evening (59%). The observed delay in appropriate dose adjustment may predispose patients to suboptimal antimicrobial exposure and subsequently therapeutic failure. CRRT was often ordered during the day shift but not initiated until evening which led to identification of potential procedural improvements. Conclusions: These data led to the initiation of a pharmacy in basket consult to alert pharmacists in real time of CRRT orders so that once CRRT was started, doses could be appropriately adjusted. Future studies to assess the impact of this process change on both time to appropriate dose and clinical outcomes are warranted.