(621) Assessment of Cefepime Dosing and the Incidence of Suspected Neurotoxicity

Introduction: In 2012 the FDA issued a safety communication recommending to reduce the dose of cefepime in patients with reduced renal function. Risk factors for developing CIN include renal dysfunction, high doses, pre-existing brain injury, elderly, increased CNS penetration, and obesity. CIN is difficult to diagnose due to its non-specific symptomology including encephalopathy, aphasia, myoclonus, seizures, and comas that start after initiation of cefepime, and resolve after discontinuation. In patients with renal injury or failure, cefepime can accumulate to toxic levels in blood and cerebral fluid. The incidence of CIN has varied throughout literature. The primary objective of this study was to assess the rate of appropriate dosing of high dose cefepime at University Hospitals Cleveland Medical Center (UHCMC). Secondary endpoints include suspected incidence of CIN in appropriately dosed versus inappropriately dosed patients, and incidence of CIN in patients with different levels of clinical pharmacy services.

Methods: This was a single-center, retrospective, chart review. Patients were identified in the electronic medical record if they received an initial dose of cefepime 2 grams every 8 hours at UHCMC from 8/1/2021-8/15/2022. There were 200 patients enrolled. CIN was defined as chart documentation of CIN, new adverse events in association with cefepime, new use of antiepileptics, EEG readings consistent with seizure activity, and/or documentation of new neurosurgery/ neurology/ psych consults. Data analysis consisted of descriptive statistics.

Results: Of the 200 patients included in this analysis, 7 patients had a suspected cefepime induced neurotoxicity (3.5%). Cefepime was initiated at an appropriate dose in 174 patients (87%). In the patients that developed CIN, the incidence was 1.7% for those who received an appropriate dose, but was 15.3% in those who were initiated on an inappropriate dose. In those with a clinical pharmacy specialist on their team, the rate of appropriate dosing of cefepime was 2% higher (89%).

Conclusions: While the overall incidence of CIN is low, it is substantially higher in our patients not dosed appropriately for renal function. Having a pharmacist on a medical team can provide extra over watch for acute changes in renal function and need for cefepime dose adjustments.