Vancomycin Pharmacokinetics in Critically Ill Patients During Accelerated Venovenous Hemofiltration

First Author(s)

• NL

  Natasha Lopez, BCCCP, PharmD (she/her/hers)

  Clinical Pharmacy Specialist, Medical Intensive Care Unit
  Massachusetts General Hospital
  Boston, Massachusetts

  Disclosure information not submitted.

Co-Author(s)

• JS

  Jonathan Sin, PharmD

  Clinical Pharmacist
  Massachusetts General Hospital, United States

  Disclosure information not submitted.
• MG

  Michael Griggs, PharmD

  Clinical Pharmacist
  Massachusetts General Hospital, United States

  Disclosure information not submitted.

Title: Vancomycin Pharmacokinetics in Critically Ill Patients during Accelerated Venovenous Hemofiltration

Introduction:  Vancomycin pharmacokinetics (PK) can be significantly affected by the use of renal replacement therapy and physiologic changes in critically ill patients. The objective of this study was to describe the PK of vancomycin during accelerated venovenous hemofiltration (AVVH) a form of prolonged intermittent renal replacement.

Methods:  This was an IRB-approved observational PK study in adult critically ill patients who received vancomycin while on AVVH. Patient’s received AVVH as a transition from continuous venovenous hemofiltration (CVVH) at ultrafiltration rates from 3-6 L/hr for 8-12 hours. Patient specific vancomycin serum concentrations were plotted against time and individual PK parameters were determined by a one-compartmental analysis. Serum concentrations must have been obtained a maximum of 4 hours prior to the start of the AVVH session as a pre-AVVH level and 2- 6 hours after the end of the AVVH as a post-AVVH level.

Results:  Nineteen patients were included with a mean age 57 + 12.9 years in which 77.8% were male with a body mass index (BMI) 30.7 + 6.1 m2 and weight 88.9 kg (68.9-98.7). The AVVH total effluent rate was 4111.11 + 582.98 mL/hr (48.42 mL/kg/hr + 12.33) for 8.95 + 1.3 hours. + 4.1 mcg/mL and 16.39 + 3.32 mcg/mL respectively. The percentage of vancomycin cleared from an AVVH session was 30.94 + 9.32, an average 3.45 + 0.89 percent per hour of AVVH. The pharmacokinetic parameter estimates rate of elimination constant (ke) and area under the curve (AUC) during AVVH were 0.04 + 0.01 hr-1 and 179.63 + 43.13 mcg.hr/mL respectively. Volume of distribution (Vd) was able to be calculated in ten patients, 76.23 + 18.01 L (0.98 + 0.27 L/kg). Patient’s required a vancomycin dose of 883.33 + 185.81 mg to maintain a serum concentration greater than 15 mcg/mL. Eleven of the nineteen patients were receiving vancomycin while on CVVH with an average vancomycin dose of 1113.64 + 171.89 mg every 24 hours, once transitioned to AVVH required 863.64 + 171.89 mg every 24 hours administered after AVVH.