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Published on: August 30, 2018
Evaluation of low-volume plasma sampling for the analysis of meropenem in clinical samples
Suzanne L Parker1, Steven C Wallis2, Cheryl Fourie2,3
1UQ Centre for Clinical Research, The University of Queensland, Brisbane, Australia. suzanne.parker@uq.edu.au.
Abstract:
Reducing the volume of blood sampled from neonatal or paediatric patients is important to facilitate research in a group that is under-represented in clinical studies. Not all patients have a cannula available for blood sampling, meaning there are real advantages in obtaining a blood microsample by skin prick. In this study, the results obtained from both capillary microsamples (CMS) and a microfluidic (MF)-CMS by skin prick are compared to conventional plasma sampled from an arterial catheter in a clinical bridging study. Six critically ill patients receiving meropenem were included with the incurred sample reanalysis test meeting the acceptance criteria for both CMS (n = 24 samples) and MF-CMS (n = 20 samples). Bland-Altman plots comparing MF-CMS to conventional arterial blood sampling revealed a difference of - 12.7 ± 22.1% (mean ± standard deviation (SD), and comparing CMS to conventional arterial blood sampling a difference of - 3.4 ± 17.0%. At - 12.7%, the bias between MF-CMS and conventional sampling is greater than the bias found with CMS, although within the limit of acceptability for analytical accuracy (that being ± 15%). Samples collected by skin prick and using CMS produced meropenem concentrations that were comparable to those obtained from conventional arterial catheter sampling. CMS samples were found to be stable when stored in the capillary tube for 24 h at 5 °C or for 4 h at room temperature.
Insights
Collecting small blood microsamples via skin prick is a viable alternative to conventional arterial sampling in critically ill children. Capillary microsamples (CMS) and microfluidic CMS provide comparable meropenem concentrations, aiding research in under-represented pediatric populations.
Area of Science:
- Clinical Chemistry
- Pharmacokinetics
- Pediatric Research
Background:
- Minimizing blood draw volumes is crucial for pediatric research, where patients are often under-represented.
- Skin prick blood microsampling offers a less invasive alternative to traditional arterial catheterization.
Purpose of the Study:
- To compare the accuracy of meropenem concentrations obtained from capillary microsamples (CMS) and microfluidic CMS (MF-CMS) via skin prick against conventional arterial blood sampling.
- To assess the stability of CMS samples for potential future research applications.
Main Methods:
- A clinical bridging study involving six critically ill patients receiving meropenem.
- Comparison of meropenem concentrations from CMS (n=24) and MF-CMS (n=20) with conventional arterial plasma samples using Bland-Altman analysis.
- Incurred sample reanalysis testing was performed to ensure analytical accuracy.
Main Results:
- Both CMS and MF-CMS showed comparable meropenem concentrations to conventional arterial sampling.
- MF-CMS exhibited a bias of -12.7 ± 22.1%, while CMS showed a bias of -3.4 ± 17.0%.
- CMS samples demonstrated stability for 24 hours at 5°C or 4 hours at room temperature.
Conclusions:
- Skin prick blood microsampling using CMS is a reliable method for determining meropenem concentrations in critically ill children.
- This minimally invasive technique can facilitate research in pediatric populations, addressing under-representation in clinical studies.
- CMS samples offer practical stability, supporting their use in various clinical research settings.
