Comparison of Fluid Flow Rates by Fluid Height and Catheter Size in Normal and Hypertensive Blood-Pressure Scenarios

Objectives: This study is performed to determine the effects of fluid height, inner catheter diameter, and peripheral venous pressure on room-temperature intravenous fluid administration. Methods: We employed the Bernoulli equation, with frictional forces considered for volumetric analysis. Results: The results of this study demonstrate that infusion-set height, catheter size, fluid type, and blood pressure significantly affect flow rates. Under normotensive conditions, flow rates ranged from 58.2 to 10,743.18 cc/h, with the highest rates observed at a 1 m infusion-set height and larger catheters. Additionally, 6% hetastarch exhibited the lowest flow rates, while 0.9% normal saline showed the highest. Under hypertensive conditions, slightly higher infusion-set elevations were required for measurable flow rates, but they remained lower than those under normotensive conditions. Conclusion: This study investigates the mechanics of peripheral venous fluid therapy and provides foundational data for future nursing research on fluid management.