Effect of Extracorporeal Membrane Oxygenation on the New Vancomycin Dosing Regimen in Critically III Patients Receiving Continuous Venovenous Hemofiltration

Background: The optimal dosing regimen of vancomycin for critically ill patients receiving continuous venovenous hemofiltration (CVVH) remains controversial, not to mention those with concurrent use of extracorporeal membrane oxygenation (ECMO). We aimed to determine if a new dosing regimen can achieve the target vancomycin trough concentration (C-trough) of 10-20 mcg/mL in patients receiving CVVH with or without ECMO. Methods: We conducted a retrospective study by enrolling patients who received vancomycin while undergoing CVVH. The vancomycin dosing regimen was 15-20 mg/kg as the loading dose and 7.5 mg/kg every 12 hours as the maintenance doses. Serum concentration was determined after at least 4 doses of vancomycin were given. Results: A total of 38 patients were enrolled, of which 21 were also on ECMO. The ultrafiltration rate of CVVH was 30.6 +/- 5.5 mL.kg(-1).h(-1) with the C-trough of 14.7 +/- 3.5 mcg/mL. C-trough was within the target range in 82% of patients. All CVVH-only patients achieved the target concentration, whereas only 76.2% of those with concurrent ECMO did (P = 0.031). Conclusions: All patients receiving CVVH achieved the target C-trough with this new dosing regimen, but those with concurrent ECMO did not. C-trough must be more closely monitored in patients using ECMO simultaneously.