Abstract
Objective: When dopamine is administered using a syringe pump, the reduction in drug infusion volume due to syringe replacement can cause hemodynamic instability. To address this, several changeover methods have been developed. This study aimed to investigate the optimal syringe changeover method by comparing the time required for syringe replacement and the drug infusion volume during replacement across different methods.
Methods: Experiment I. The time required for syringe replacement using the standard syringe changeover method and the flushing method was compared using the Mann-Whitney U test, and the volume of dopamine solution not infused during syringe replacement was estimated. Experiment II. At dopamine infusion rates of 3.6 ml/h (general initial rate) and 6.0 ml/h (standard rate), the dopamine infusion volume over 60 min after syringe replacement was compared between the on-off method or double pumping method and standard syringe changeover method.
Results and Discussion: There was no significant difference in syringe replacement time between the standard syringe changeover method and the flushing method. The volume of uninfused dopamine solution during the syringe replacement period was less than 0.1 ml for both flow rates. At a flow rate of 3.6 ml/h, the volume of dopamine infused 10 min after the start of infusion was significantly larger with both the double pumping method and the on-off method compared with the standard method. At 30 min and between 50 to 60 min, only the on-off method showed a significantly larger infusion volume compared with the standard method. At a flow rate of 6.0 ml/h, no significant differences were observed at any time point. These findings suggest that higher flow rates may reduce the impact of frictional resistance.
