Effects of flow rate accuracy in two-day anticancer drug infusion with disposable pumps on plasma drug concentrations.

BACKGROUND

Elastomeric pumps have a curved infusion rate profile over infusion time. Chemically driven pumps can overcome such limitations of elastomeric pumps and infuse constantly. However, studies on the pharmacokinetic benefit of chemically-driven pumps are insufficient.

OBJECTIVE

This study aimed to determine effects of constant infusion with a chemically-driven pump on plasma drug concentrations compared to elastomeric pumps.

METHODS

Infusion rate profiles of a chemically driven pump and two elastomeric pumps were measured in vitro tests under three height conditions of drug reservoir. Plasma drug concentrations were estimated using a pharmacokinetic model of 5-fluorouracil (5FU).

RESULTS

The chemically-driven pump was more accurate than elastomeric pumps during the total infusion time (Root-mean-square-error (RMSE): 3% vs. 13%) which thus reduced its deviation of plasma 5FU concentration over time to one-fifth of that with an elastomeric pump. The chemically-driven pump had less than 5% of RMSE despite the influence of height difference.

CONCLUSION

Although chemically-driven pumps maintained plasma 5FU concentration successfully and elastomeric pumps did not, both pumps were proper for 5FU infusion because the time-dependent changes in infusion rate did not affect the area under the curve. Chemically driven pumps would be more advantageous for drugs that are sensitive to their plasma concentrations.