A new method for rapid fluid bolus infusion into a peripheral vein

Efficacy of Rapid Fluid Administration Using Various Setups and Devices

OBJECTIVES

In clinical practice, there are various methods that can be used for the rapid administration of fluid in infants and children. The current study prospectively evaluates gravity, pressure-assisted, and hand-pump methods for the rapid administration of fluid using an in vitro model.

METHODS

Thirty participants were asked to deliver 500 mL of fluid using 1 of 6 setups: (1) standard blood tubing with gravity administration, (2) standard blood tubing with pressure bag maintained at 300 mm Hg, (3) standard blood tubing with pressure bag inflated to 300 mm Hg and left to flow, (4) blood tubing with in-line bulb pump, (5) blood tubing with in-line bulb pump and pressure bag, and (6) standard blood tubing with 20-mL syringe attached to the stopcock for a push-and-pull technique using a 20-mL syringe.

RESULTS

The blood tubing with an in-line bulb pump to allow manual acceleration of the administration of fluid along with a pressure bag on the intravenous fluid bag achieved the fastest flow rate, requiring an average of 98 seconds to deliver 500 mL of fluid.

CONCLUSIONS

When considering factors that affect fluid administration, Poiseuille's law dictates that the most important variable is the radius of the intravenous cannula, whereas the length of the cannula and the viscosity of the fluid administered are of secondary importance. With these limitations in mind, other factors may be used to speed fluid administration. Our study demonstrates the advantage of using blood tubing with the in-line bulb pump combined with a pressure bag.

Novel rapid infusion device for patients in emergency situations

Rapid fluid administration is often required for resuscitation when patients are admitted in emergency department with hypovolemic shock or excessive blood loss. Various methods have been described earlier to increase the fluid administration speed. Larger vein size, larger bore cannula, height of fluid, pressure over fluid bottle etc. are some of methods described in such situations.We here describe a novel method to administer intravenous fluid rapidly and this method can be utilized in emergency and trauma settings.

The effect of IV cannula length on the rate of infusion

According to the Hagen-Poiseuille's law, rate of laminar flow through a tubular structure varies directly with fourth power of its radius and inversely with its length. Although it is well recognised that faster infusion rates can be achieved with wider-bore IV cannulae, the effect of length on flow rates is less well known. In the current in vitro study, we assessed the effect of length of an IV cannula on the rate of flow of infusion. Mathematical calculations performed using Hagen-Poiseuille's law predicted an increase of 40% in flow rates when the IV cannulae were shortened by 13mm. However, when the flow rates of the shortened cannulae were measured in vitro an increase of only 4-18% was observed. Although the increase in flow rates was statistically significant, it may not be sufficient to be significant in clinical practice. Turbulence resulting from design characteristics of the infusion system is responsible for the measured flow rates to be lower than that predicted by mathematical calculations.