Jonathan Birabaharan, BS
PhD Candidate
Pharmaceutical Sciences, Center for Clinical Pharmaceutical Sciences, University of Pittsburgh, United States
Disclosure information not submitted.
Raymond E. West III, PhD
Research Lab Coordinator
Pharmacy and Therapeutics, University of Pittsburgh, United States
Disclosure information not submitted.
Thomas D. Nolin, PharmD, PhD
Associate Professor
Pharmaceutical Sciences, University of Pittsburgh, United States
Disclosure information not submitted.
Chani Traube, MD, FAAP, FCCM
Pediatric Intensivist, Clinical Researcher
NewYork Presbyterian Hospital
New York, New York, United States
Disclosure information not submitted.
Michael Bell, MD
Division Chief
Childrens National Health System, United States
Disclosure information not submitted.
Philip E. Empey, BCPS, PharmD, PhD
Associate Professor, Pharmacy and Therapeutics
University of Pittsburgh, United States
Disclosure information not submitted.
Title: A sensitive UPLC-MS/MS assay to measure a panel of sedatives in plasma from critically ill children.
Introduction: Increased exposure sedatives is a known delirium risk factor in critically ill children. Decreased drug clearance may predict occurrence and severity. We are conducting a multicenter clinical trial using population pharmacokinetic modeling of drug concentrations as a novel approach to determine dose-concentration-outcome relationships. However, limited blood sampling availability in critically ill children and need for multiple assays to quantify a variety of commonly used sedatives creates logistical challenges. The goal of this project was to develop a sensitive and specific assay for the simultaneous quantification of midazolam (MDZ), alpha hydroxymidazolam (1- OH MDZ), dexmedetomidine (DEX), morphine (MOR), morphine-3-glucuronide (M3G), morphine-6-glucuronide (M6G), fentanyl (FEN), norfentanyl (NF), and hydromorphone (HM) in small volume pediatric samples.
Methods: A sensitive and efficient UPLC-MS/MS method was developed for all previously mentioned sedatives following FDA guidance for bioanalytical validation. Analyte separation was achieved using a gradient mixture of (A: 0.15% formic acid in water and B: Acetonitrile) and a Waters Acquity C18, 1.7um (2.1 x 100mm) column. Minimal sample preparation consisting of simple protein precipitation extraction using acetonitrile was utilized. A total of 52 plasma samples collected over multiple time points from 7 different patients were analyzed.
Results: Assays were linear over the clinical concentration ranges: MDZ, MOR, HM: 0.5-125ng/mL; 1-OH MDZ, M3G, M6G: 5-500ng/mL; and DEX, FEN, NF: 0.05-7.5ng/mL (R 2> 0.99 for all). Lower limits of quantification were 0.5 ng/mL, 5 ng/mL and 0.05 ng/mL, respectively. Assay run time was 10 min and required only 100uL of plasma. Sedatives were quantifiable in all samples from the 7 patients with only 7 of the 52 needing to be reanalyzed after dilution due to exceeding the linear range for MDZ.
Conclusions: We developed a novel method to measure a total of 9 different analytes (5 sedatives, 4 metabolites) simultaneously. This highly sensitive and specific assay enables comprehensive sedative population PK modeling to understand altered dose-concentration-outcome relationships in pediatric ICU patients.
Research/Grant Support: NICHD 1R01HD099284-01(PI: Empey/ Bell/Traube). NIH TL1 TR001858 (PI: Kraemer, Kevin)