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Published on: May 26, 2014
Microbial growth and importance of flushing inside closed-type infusion devices during administration of lipid
Sachiko Omotani1, Yasutoshi Hatsuda1, Yasuhiro Katsui1
1Faculty of Pharmacy, Osaka Ohtani University.
Abstract:
Background: We investigated the extent of growth of microorganisms with simultaneous administration of lipid emulsions with infusions for Total Parenteral Nutrition (TPN), assuming that the lipid emulsions contaminated with microorganisms are stagnant in a closed-type infusion device. We also investigated if bacterial growth can be prevented in the infusion device by flushing the inside of the infusion device with saline solution after the administration of lipid emulsion from the side tube in vitro setting. Methods: We made a preparation by adding Escherichia coli to the lipid emulsion and started the infusion simultaneously with the infusion solution for TPN and lipid emulsion with the piggyback method. Immediately after the completion of lipid emulsion infusion, we conducted flushing with saline solution. The volume of saline solution was none, 5, 10, or 20 mL at a flow rate of 1 mL/s. Infusion solution that was stagnant in the infusion device was collected immediately before completing the lipid emulsion infusion and 20 h after flushing, i.e., 24 h after starting the infusion for TPN, and the number of viable bacteria was determined. Results: The number of viable E. coli increased in the infusion device of all three species used in this experiment 24 h after starting the lipid emulsion infusion without flushing. We found that bacterial growth could be prevented through flushing with saline solution after the completion of lipid emulsion infusion and flushing out the stagnant infusion solution in the closed-type infusion device. Conclusions: We found that if E. coli was present in the closed-type infusion device, it would multiply. We also found that the number of viable bacteria varied according to the variety and internal structure of the closed-type infusion device as well as the liquid volume used for flushing, although flushing can prevent the growth of microorganisms. Proper management and manipulation of infusion is required to prevent infection.
Insights
Bacterial contamination in lipid emulsions used for Total Parenteral Nutrition (TPN) can lead to microbial growth within infusion devices. Flushing infusion devices with saline post-infusion effectively prevents bacterial proliferation, ensuring patient safety.
Area of Science:
- Microbiology
- Clinical Pharmacy
- Infection Control
Background:
- Investigated microbial growth in lipid emulsions administered with Total Parenteral Nutrition (TPN).
- Assessed bacterial proliferation in stagnant lipid emulsions within closed infusion devices.
- Explored the efficacy of saline flushing to prevent microbial contamination in infusion devices.
Purpose of the Study:
- To determine the extent of microbial growth in lipid emulsions during TPN.
- To evaluate the effectiveness of saline flushing in preventing bacterial growth in infusion devices.
- To identify factors influencing bacterial proliferation and the efficacy of flushing.
Main Methods:
- Introduced Escherichia coli into lipid emulsion and infused simultaneously with TPN solution.
- Flushed infusion devices with varying volumes of saline (0, 5, 10, 20 mL) post-infusion.
- Quantified viable bacteria in stagnant infusion solution collected before and 24 hours after TPN infusion.
Main Results:
- Significant increase in viable E. coli observed in infusion devices without flushing after 24 hours.
- Saline flushing effectively prevented bacterial growth in the infusion devices.
- Bacterial counts varied based on infusion device type, internal structure, and saline flush volume.
Conclusions:
- E. coli readily multiplies within closed infusion devices when present in lipid emulsions.
- Post-infusion saline flushing is a critical intervention to prevent microbial growth.
- Careful management of TPN infusions and infusion devices is essential for infection prevention.
