Evaluating pulsatile flushing by pushing method and catheter size for educating nurses on peripheral vascular patency: a computational fluid dynamics simulation analysis

Background: Maintaining the patency of peripheral intravenous catheters is essential for preventing occlusion and catheter-related complications. Clinical guidelines and field education emphasize the effectiveness of pulsatile flushing for this purpose. However, due to the absence of standardized methods, its implementation among clinical nurses remains low. This study aimed to compare the effects of pulsatile flushing according to different infusion methods and catheter sizes to support the education of clinical nurses on intravenous infusion therapy. The findings aim to provide foundational data for effectively implementing pulsatile flushing in practice. Methods: A simulation analysis using computational fluid dynamics was employed. The study investigated optimal pulsatile flushing techniques for various peripheral intravenous catheter sizes (20G, 22G, and 24G) by assessing the volume ratio of 0.9% sodium chloride to blood, 0.9% sodium chloride velocity, and maximum wall shear stress. Simulations were conducted with infusion volumes of 0.5, 1.0, 1.5, and 2.0 ml over 0.5–1 s, including a 0.4-second pause, through catheters placed in the basilic vein. Results: Pulsatile flushing effects varied according to infusion method and catheter size. Increased infusion volume and decreased infusion time led to higher 0.9% sodium chloride volume ratios and velocities, improving perfusion effectiveness. However, wall shear stress sometimes exceeded the safe threshold of 2 Pa, posing a risk of vascular damage. Considering 0.9% sodium chloride volume ratio, velocity, recirculation turbulence at the catheter tip, and wall shear stress, the most effective flushing methods for 20G, 22G, and 24G catheters were infusing 1 ml, 0.5–1 ml, and 0.5 ml of perfusate over 1 s, respectively. Conclusions: To ensure effective and safe pulsatile flushing in nursing practice, infusion volume and rate should be adjusted according to catheter size. The findings contribute foundational data to guide standardized, evidence-based flushing practices in nursing and has policy implications for revising clinical guidelines and enhancing nurse training programs to ensure safer and more effective intravenous catheter management.