Dosing Errors Due To Flow Rate Variability In Multi-Infusion Therapy Setups: Comparision Between A Syringe Pump And A Cylinder Pump

Introduction: In critically ill patients, multiple drugs or fluids are often infused through the same line simultaneously. Several previous studies reported on dosing errors due to flow interactions when multiple drugs with various flow rates are infused through the same line. However, a newly developed cylinder pump, which combined the advantages of infusion pump and syringe pump, can prevent free flow or siphoning phenomenon, allowing more accurate drug delivery without being affected by the surrounding environment. Objectives/Aims: The aim of this study was to compare a new generation cylinder pump with a conventional syringe pump to check for dosing errors of slow-rate drug when infused through the same line with the rapid-rate drugs. Methods: The visible dye indigo carmine infused at a rate of 0.5 ml/h was used as a model drug. The experiment was setup to model a clinical drug delivery system through a four-stopcock linear manifold and a catheter lumen. The rate of carrier fluid was fixed at 15ml/h. After first drug reached a steady-delivery state, second drug with a 2ml/h rate was initiated. The dye delivery was measured quantitatively using a spectrophotometry. Experiments were conducted with the conventional syringe pump (Injectomat MC Agilia, Fresenius Kabi) and a new generation cylinder pump (H-100, Meinntech, Korea), respectively. Results: Starting second drug infusion in the multi-infusion setups caused a transient unintentional bolus of the first drug. Stopping a second drug infusion caused a transient reduction in the first drug delivery. However, in case of cylinder pump, its own cartridge acted as an anti-reflux valve to prevent free-flow and siphoning phenomenon. Conclusion: Regardless of the used infusion device, delivery of one infused drug was transiently affected by starting or stopping a second drug infusion in the same line. Accidental free-flow and siphoning phenomenon may be reduced in the cylinder pump.