Clinician perspectives on inpatient cystatin C utilization: A qualitative case study at Mayo Clinic.

INTRODUCTION: Serum creatinine (SCr) testing has been the mainstay of kidney function assessment for decades despite known limitations. Cystatin C (CysC) is an alternative biomarker that is generally less affected than SCr by pertinent non-renal factors in hospitalized patients, such as muscle mass. Despite its potential advantages, the adoption of CysC for inpatient care is not widespread. At one hospital with CysC testing, we demonstrated a significant rise in non-protocolized use over the last decade. This study uses qualitative methods to provide the first report of how clinicians understand, approach, and apply CysC testing in inpatient care. METHODS: Fifteen clinicians from various disciplines were interviewed about their experience with inpatient CysC testing. The semi-structured interviews were audio-recorded, transcribed verbatim, and analyzed thematically using a phenomenological approach. RESULTS: Knowledge and confidence with CysC varied greatly. Clinicians reported first learning about the test from colleagues on consulting services or multidisciplinary teams. The majority believed CysC to provide a more accurate measure of kidney function than SCr. Common scenarios for CysC ordering included medication dosing, evaluation of acute kidney injury, and a thorough evaluation of kidney function in patients with risk factors for an altered SCr. Facilitators for ordering CysC included the availability of rapid results turnaround and the automated calculation of glomerular filtration rate based on the biomarker. Barriers to use included a lack of education about CysC, and the absence of an institutional protocol for use. DISCUSSION: Clinicians at our site decided independent of institutional guidance whether and when CysC added value to patient care. While the majority of study participants indicated advantages to rapid turnaround CysC testing, its use depended not just on the features of the specific case but on clinician familiarity and personal preference. Findings from this research can guide the implementation and expansion of CysC testing.

Effects of Cannabidiol on Morphine Conditioned Place Preference in Mice.

This study sought to determine whether the cannabis constituent cannabidiol attenuates the development of morphine reward in the conditioned place preference paradigm. Separate groups of mice received either saline or morphine in combination with one of four doses of cannabidiol using three sets of drug/no-drug conditioning trials. After drug-place conditioning, morphine mice displayed robust place preference that was attenuated by 10 mg/kg cannabidiol. Further, when administered alone, this dose of cannabidiol was void of rewarding and aversive properties. The finding that cannabidiol blocks opioid reward suggests that this compound may be useful in addiction treatment settings.