Transcutaneous theophylline collection in preterm infants

Area of Science:

• Neonatal pharmacology
• Dermatology
• Analytical chemistry

Background:

• Theophylline is commonly prescribed for preterm infants.
• Monitoring plasma theophylline levels is crucial for therapeutic efficacy and safety.
• Current monitoring methods require blood draws, which can be invasive for neonates.

Purpose of the Study:

• To evaluate a novel transcutaneous collection system for theophylline and its metabolite, caffeine, in preterm infants.
• To assess the correlation between transcutaneously collected drug amounts and plasma drug concentrations.
• To determine the feasibility and safety of transcutaneous drug collection in neonates.

Main Methods:

• A novel adhesive transcutaneous collection system with an activated charcoal-gel matrix was used.
• The system was applied to 33 preterm infants (2-89 days old) receiving theophylline therapy.
• Collections were performed for 4-12 hours, with simultaneous blood sampling for plasma drug level monitoring.

Main Results:

• Transcutaneous collection successfully gathered theophylline and caffeine.
• Collected amounts showed significant correlation with average plasma drug concentrations and postconceptional age (p < 0.01).
• Skin reactions were minimal, primarily mild erythema.

Conclusions:

• The novel transcutaneous collection system can effectively collect theophylline and caffeine from the skin surface of preterm infants.
• Collected amounts correlate with plasma concentrations, suggesting a diffusion process.
• The system, however, demonstrated poor predictive value for individual plasma drug concentrations.