Comparison of one vs. two blood samples for determination of tobramycin AUC in children with cystic fibrosis

Norris, R. L. G., Barras, M., Alraman, H., Kirkpatrick, C., Dakin, C., Harris, M. and Jess, K. (2011). Comparison of one vs. two blood samples for determination of tobramycin AUC in children with cystic fibrosis. In: 12th International Congress of Therapeutic Drug Monitoring and Clinical Toxicology. 12th International Congress of Therapeutic Drug Monitoring and Clinical Toxicology, Stuttgart, Germany, (513-513). 2-6 October 2011. doi:10.1097/01.ftd.0000400651.94145.ba


Author Norris, R. L. G.
Barras, M.
Alraman, H.
Kirkpatrick, C.
Dakin, C.
Harris, M.
Jess, K.
Title of paper Comparison of one vs. two blood samples for determination of tobramycin AUC in children with cystic fibrosis
Conference name 12th International Congress of Therapeutic Drug Monitoring and Clinical Toxicology
Conference location Stuttgart, Germany
Conference dates 2-6 October 2011
Proceedings title 12th International Congress of Therapeutic Drug Monitoring and Clinical Toxicology   Check publisher's open access policy
Journal name Therapeutic Drug Monitoring   Check publisher's open access policy
Place of Publication Philadelphia PA, United States
Publisher Lippincott Wiliams & Wilkins
Publication Year 2011
Sub-type Published abstract
DOI 10.1097/01.ftd.0000400651.94145.ba
Open Access Status Not Open Access
ISSN 0163-4356
1536-3694
Volume 33
Issue 4
Start page 513
End page 513
Total pages 1
Language eng
Formatted Abstract/Summary
Aims: The therapeutic range for tobramycin in cystic fibrosis (CF) is an AUC between 70 – 100 mg l hr– 1. Currently, 2 blood concentrations are required to estimate the AUC, which is costly, painful to the patient and often difficult to coordinate. A model-based Bayesian predictive program (TCIWorks®) is available which requires evaluation in the clinical setting. The aim of this project was to retrospectively evaluate the accuracy of an AUC estimated using one blood concentration as compared with an AUC based on two concentrations using TCIWorks®.

Methods: Data were collected from CF patients admitted on once daily IV tobramycin. Each patient had 2 blood samples taken according to usual clinical practice, on 2 separate occasions. Dosing data, tobramycin concentrations and patient demographics from the first occasion were entered into TCIWorks® to establish the patient pharmacokinetic model. Using this model, data from the second occasion were used to estimate an AUC from 1 concentration (AUC1) and from 2 concentrations (AUC2). Two patient groups were analysed. Group 1 comprised 14 children where accurate sampling and administration times were obtained. Group 2 included a different group of 16 children where the sampling and dosing times were obtained from patient charts.

Results: Key results are shown in Table 1: In group 1, AUC1 correlates highly with AUC2 (P< 0.001), with minimal bias. Despite data being less accurate in the total population, the correlation is still high (P< 0.001). Conclusion: TCIWorks® required only 1 blood sample to calculate an AUC, once an individual patient model was established. A prospective study is required to confirm this finding. 
Keyword Cystic fibrosis
Tobramycin
Bayesian
Q-Index Code CX
Q-Index Status Confirmed Code
Institutional Status UQ

Document type: Conference Paper
Collections: Non HERDC
School of Pharmacy Publications
 
Versions
Version Filter Type
Citation counts: TR Web of Science Citation Count  Cited 0 times in Thomson Reuters Web of Science Article
Google Scholar Search Google Scholar
Created: Sun, 21 Aug 2011, 12:03:00 EST by System User on behalf of School of Pharmacy