Use of cytotoxic drugs with an end-line filter--a study of four drugs commonly administered to paediatric patients

Drug retention by inline filters--effect of positively charged polyethersulfone filter membranes on drug solutions with low concentration

OBJECTIVE

The use of infusion filters in pediatrics is controversially discussed. Their application is an excellent opportunity to prevent complications, but there are researchers, who do not see any advantage in using inline filters. This paper describes the interaction of five different drugs with a positively charged as opposed to an uncharged polyethersulfone (PES(+) versus PES(0)) membrane.

METHODS

To measure the extent and the mechanism of interaction, PES(+) versus PES(0) membranes and furosemide sodium, potassium canrenoate, digitoxin, digoxin and adenosine, each 30μmol/l, were investigated. Salt ions with different hydrodynamic radii and different concentrations have been used in the eluents.

RESULTS

During furosemide sodium and potassium canrenoate filtration with PES(+), the onset of UV absorption depends on the electrolyte concentration in the eluent: the lower the electrolyte concentration the later the onset of UV absorption. A correlation between the hydrodynamic volume of the different salt ions used and the onset of UV absorption could be proven for both substances: The larger the hydrodynamic volume of the extrinsic ion, the later the onset of the UV absorption if the same electrolyte concentration was used. Due to a higher structural density of PES(+) than PES(0) a delayed onset of UV absorption during filtration of digitoxin and digoxin with the PES(+) membrane could be observed. No correlation between the hydrodynamic volume of the different salt ions used and the onset of UV absorption could be seen. With adenosine neither the filter type nor the electrolyte concentration or the hydrodynamic volume of the salt ions had an influence on the onset time of absorption.

CONCLUSION

The results obtained with the anionic drugs investigated are particularly relevant if low drug concentrations in a saltless infusion solution are applied in combination with a charged filter membrane. Therefore, for each infusion formulation, a careful selection of the filter material is essential.

Simulated infusion of paclitaxel with in-line filters

BACKGROUND

Paclitaxel is one of the most effective anticancer drugs ever developed. To prevent hazards associated with intravenous (IV) administration which include the formation of microbubbles, microbiological contamination and particulate matter, the suppliers recommend that an in-line IV filter should be used during the infusion of the chemotherapeutic agent.

METHODS

To rule out the possibility that polyethersulfone (PES) membranes retain the paclitaxel during filtration, we carried out specific tests. Paclitaxel retention by PES in-line IV filters was evaluated by a simulated-drug IV infusion and high-performance liquid chromatography analysis.

RESULTS

In our model of study, no variation of paclitaxel concentration was revealed before and after filtration using two different filter devices.

CONCLUSIONS

The results suggest that, under our experimental conditions, paclitaxel concentration in saline solution remains constant before and after filtration. Indeed, our study indicates that the filters analyzed herein, other than preventing hazards associated with IV administration, do not retain paclitaxel, thus avoiding the reduction of the drug concentration and potency during filtration.

Contamination Control in Nursing With Filtration

Filters often are viewed as screens with openings smaller than the particles intended to be removed by a process technically known as direct interception. However, filter manufacturing embraces far more advanced technological approaches, with an evolution toward selective removal of cells or soluble constituents from complex physiologic solutions. An appreciation of filtration development makes it easy to understand how differently manufactured filters with the same claims may not perform identically. This article focuses on the filtration of intravenous solutions and point-of-use hospital water.

Filters in anaesthesia and intensive care

The use of various types of filters in anaesthesia and intensive care seems ubiquitous, yet authentication of the practice is scarce and controversies abound. This review examines evidence for the practice of using filters with blood and blood product transfusion (standard blood filter, microfilter, leucocyte depletion filter), infusion of fluids, breathing systems, epidural catheters, and at less common sites such as with Entonox inhalation in non-intubated patients, forced air convection warmers, and air-conditioning systems. For most filters, the literature failed to support routine usage, despite this seemingly being popular and innocuous. The controversies, as well as guidelines if available, for each type of filter, are discussed. The review aims to rationalize the place of various filters in the anaesthesia and intensive care environment.