Can capillary microsampling facilitate a clinical pharmacokinetics study of cefazolin in critically ill children?

Area of Science:

• Pediatric Pharmacology
• Clinical Chemistry

Background:

• Pharmacokinetic studies in children are crucial but often hindered by difficulties in blood sample collection.
• Conventional blood sampling methods can be invasive and challenging in pediatric populations.

Purpose of the Study:

• To evaluate the reliability of capillary microsampling compared to conventional sampling techniques for pharmacokinetic analysis of Cefazolin in children.
• To assess the feasibility of using capillary microsampling in pediatric pharmacokinetic studies.

Main Methods:

• Paired blood samples were collected from 12 pediatric patients (median age/weight: 49 months/18 kg).
• Capillary microsampling and conventional venous blood sampling techniques were employed.
• Analysis utilized United States Federal Drug Administration (FDA) incurred sample reanalysis acceptance criteria.

Main Results:

• 79% of paired samples met the FDA criteria (difference < 20% magnitude) with a capillary microsampling bias of -10% (SD 20%).
• Excluding pharmacokinetic outliers, agreement improved to 88%.
• Results indicate high concordance between the two sampling methods.

Conclusions:

• Capillary microsampling is a reliable and acceptable method for pediatric pharmacokinetic studies.
• This technique meets established acceptance criteria for bioanalysis.
• Capillary microsampling offers a viable alternative to conventional methods, facilitating drug research in children.