Evaluation of catabolic response in neurologically injured patients with augmented renal clearance (RPA Pilot/ Seed Project)

Augmented renal clearance (defined as a creatinine clearance > 130ml/min) is present in the majority of critically ill patients. The presence of ARC in patients receiving antibiotics such as vancomycin or beta-lactams may cause subtherapeutic concentrations, which may lead to therapeutic failure. Monitoring for ARC is important for patients at risk in order to ensure appropriate dosing of essential medications in critically ill patients. The gold standard for identification of ARC in critically ill patients is an 8-hour urine creatinine clearance measurement, which is limited by the accuracy and stability of the urine collection. The ARCTIC score can also be helpful in predicting the likelihood of ARC, but has not been used to describe the extent, variability, or progression of ARC and has not proven to be sufficiently sensitive or specific for reliable clinical use. Patients with critical illness often exhibit hypercatabolism as a result of the inflammatory response attendant with their critical illness. This results in an increased caloric need, increased muscle wasting, and immune dysfunction. The gold standard for evaluating metabolic needs for critically ill patients at the bedside is a metabolic cart study (indirect calorimetry). There are gaps in knowledge regarding the link between hypercatabolism and ARC. Additionally, there is a gap in knowledge related to biomarkers which may help predict the presence and extent of ARC. This study aims to begin to explain potential etiologies for ARC and identify biomarkers which may aid clinicians in identifying the presence and extent of ARC.