Wieruszewski, Patrick M.

AbstractBackgroundAccurately estimating glomerular filtration rate (GFR) is crucial for dosing medications in hospitalized patients. Due to limitations of serum creatinine for GFR estimation, serum cystatin C (CysC) has been explored as an alternative functional kidney biomarker. This study assessed discordance between eGFRCr and eGFRCysC in a large sample of hospitalized patients and examined the frequency of renally eliminated medications affected by eGFR discordance.MethodsThis multisite historical study included adults hospitalized between 2011 and 2023 with CysC and serum creatinine reported within 24 h of each other. The first concurrent biomarker pair for each patient was analyzed. eGFR discordance and use of renally eliminated medications were described.Results17,718 hospitalized patients with concurrent creatinine and CysC assessments were included. The median eGFRCr was 65 mL/min, and the eGFRCysC was 46 mL/min. The median absolute difference of eGFRCr−eGFRCysC was 15 mL/min, and 7972 patients (45%) had a > 30% absolute difference. There was a significantly greater percentage of patients with an eGFR <30 mL/min based on eGFRCysC (26%) compared to eGFRCr (15%) (p < 0.001). Patients were prescribed an average of 20 medications in the 24 h surrounding the concurrent biomarker assessment. Renally eliminated medications accounted for 39% ± 13% of medication orders, and 80% of patients with eGFR discordance were prescribed five or more renally eliminated medications.ConclusionSubstantial eGFR discordance between eGFRCysC and eGFRCr was observed in hospitalized patients, which directly affects the dosing of renally eliminated medications. Further research is needed to optimize the pharmacotherapy of renally eliminated medications with discordant GFR assessments to improve medication safety and effectiveness.

Abstract: Extracorporeal membrane oxygenation (ECMO) is a mechanical support treatment modality used in patients with refractory cardiac and/or pulmonary failure. Bleeding and thrombotic complications associated with ECMO are inherent concerns that require careful management. Anticoagulation optimization may help mitigate these risks by providing more adequate therapeutic anticoagulation and lessen the bleed risk. Heparin, the most used anticoagulant, carries concerns for heparin-induced thrombocytopenia and possible resistance given its dependence on cofactors and circulating proteins to exert its pharmacologic effect. In contrast, bivalirudin, a direct thrombin inhibitor, exerts its effect independent of cofactors or plasma proteins, and possesses thrombin-binding and metabolism features that may confer advantages in ECMO management. This review of the evidence for bivalirudin utilization in ECMO suggests favorable outcomes in circuit-related thrombosis, bleeding, and dosing reliability. In addition, blood product utilization, circuit interventions, and success in ECMO decannulation and survival were positive findings associated with bivalirudin that merit consideration. Common questions and concerns relative to bivalirudin utilization, including laboratory monitoring, utilization in low-flow states, dosing considerations in renal replacement therapy, reversibility, and cost are also discussed in this review. Moreover, this review suggests that bivalirudin utilization presents the opportunity for ECMO management simplification.