WHAT IS THE MAXIMUM TEMPERATURE REACHED IN ELASTOMERIC DEVICES UNDER SIMULATED OPAT CONDITIONS?

Area of Science:

• Pharmaceutical Sciences
• Drug Delivery Systems
• Clinical Pharmacy

Background:

• Outpatient parenteral antimicrobial therapy (OPAT) is increasingly used for cost savings in the NHS.
• There is a lack of stability data for antibiotics in elastomeric devices under real-world conditions.
• Current stability testing guidelines assume a worst-case temperature of 37°C, but evidence for this is lacking.

Purpose of the Study:

• To determine the actual temperature reached by solutions in elastomeric devices under simulated patient use.
• To provide data to inform more realistic stability testing conditions for OPAT medications.
• To investigate the influence of clothing on device temperature.

Main Methods:

• Two types of elastomeric infusion devices (Baxter Infusor LV 10 and I-Flow Homepump Eclipse® C-Series) were used.
• Miniature Type K Thermocouples monitored temperature in devices filled with sterile water.
• Devices were subjected to refrigeration followed by ambient conditions, simulating daily patient activities including wearing under clothing.

Main Results:

• The Baxter Infusor (BI) showed slower temperature changes compared to the I-Flow (IFHE) device, both during cooling and warming.
• Maximum temperatures reached when worn under clothing were 28.1°C for the BI and 23.4°C for the IFHE.
• Average maximum temperatures when worn without clothing were 23.3°C (BI) and 23.8°C (IFHE).

Conclusions:

• The study demonstrates that temperatures experienced by OPAT devices under clothing are often lower than the assumed 37°C.
• A suggested testing temperature of 30°C is proposed to account for body temperature variations and warmer ambient conditions.
• These findings support more realistic stability testing to prevent the unnecessary exclusion of drugs from OPAT.