Scientific Poster Session III - Residents and Fellows Research-in-Progress

Residents and Fellows Research in Progress
  Monday, October 14, 2024
  01:00 PM–02:30 PM

Abstract

Introduction:

Vancomycin (VAN) is crucial for treating gram-positive infections, particularly methicillin-resistant Staphylococcus aureus (MRSA) bacteremia. Due to its narrow therapeutic index and interpatient variability, therapeutic drug monitoring (TDM) is essential. The 2020 ASHP/PIDS/SIDP/IDSA vancomycin monitoring guidelines recommend targeting an AUC₂₄/MIC of 400-600mg*h/L. Notably, guidelines do not address pregnant patients. Some studies demonstrated similar AUC_0-24 between pregnant and non-pregnant patients.

Pregnancy-induced physiological changes can alter VAN’s volume of distribution and clearance. Data surrounding the dosing of VAN in maternal sepsis is limited and conflicting; some studies suggest that 20mg/kg IV Q8H general dosing provides 75-90% target attainment for pregnant patients while others suggest that this regimen poses considerable risk to mother and newborn.

This study aims to characterize VAN AUC_0-24 following a loading dose in pregnant patients and analyze factors affecting target AUC attainment.

Research Question or Hypothesis:

Does the standard 20mg/kg VAN loading dose achieve VAN pharmacokinetic targets between troughs and AUC₂₄/MIC in pregnant patients?

Study Design: Retrospective descriptive study

Methods:

Vigilanz will be used to identify patients who received VAN IV from January 1^st, 2022 to December 31^st, 2022. Pregnant patients admitted to maternal units with appropriately timed levels were screened for inclusion. At Loma Linda University Medical Center, the VAN protocol for maternal sepsis patients is to give VAN 20mg/kg IV as a loading dose. Then, two levels are ordered at 6 and 12 hours after end of infusion to calculate patient-specific PK and to provide dosing recommendations. Given dose-serum concentration proportionality, doses are adjusted to goal troughs 10-15mg/dL. Regression analysis will be performed to analyze factors affecting target attainment of AUC_0-24 (including albumin, actual body weight, fat free mass, renal function, duration, preterm labor).

Patients who received non-intravenous formulations, continuous VAN infusion, renal replacement therapies, or had VAN MIC>2 were excluded.

Results:

Research ongoing

Conclusion:

Research ongoing

Presenting Author

Anthony Huynh PharmD
Loma Linda University Health

Authors

Jacinda Abdul-Mutakabbir PharmD, MPH, AAHIVP
Skaggs School of Pharmacy and Pharmaceutical Sciences

Karen Tan PharmD, BCIDP
Loma Linda University Medical Center