What?

To improve the accuracy and efficiency of patient treatment, methods need to be developed for the reliable and accurate delivery of drugs to patients. In order to do this, the metrological infrastructure for pharmaceutical drug delivery needs improvement; it requires validated primary standards for flow rates from 100 ml/min down to 10 nl/min, the characterisation of flow meters and flow generators and the validation of infusion pumps. The existing primary standard goes down to 16 ul/min, however below 100 ml/min there has never been a formal validation of primary standards by means of a (key) comparison.

The extremely low flow rates are not easy to measure. Different parameters affect the infusion pump flow rate and hence the drug delivery, for example the drug type (e.g. viscosity), (hydrostatic) pressure, temperature and pump usage pattern. Flow rate (and concentration) accuracy deteriorates further if multi-pump infusion is involved. An additional issue with drug delivery is that typically the drug delivery characteristics are not known and understood, for example the time it takes to reach a stable flow rate. This can also result in unexpected flow rates.

This joint research project requires a close cooperation with experts and practitioners from the relevant medical areas and will lead to:

• traceable calibration services for drug delivery systems for flow rates down to 1 nl/min transfer standards for onsite calibration
• assessment of the drug delivery devices
• a best practice guide for drug delivery