Particle leakage in extracorporeal blood purification systems based on microparticle suspensions.
OBJECTIVE
The newly developed 'Microspheres based Detoxification System' (MDS) designed for any extracorporeal adsorption therapy uses microparticles as adsorbents characterized by a size of 1-20 microm in diameter which are recirculated in the secondary (filtrate) circuit connected to a hollow fiber filter located in the primary (blood) circuit. In the case of a leakage or rupture in the hollow fiber filter, microspheres can enter patients' blood circuits and cause embolic episodes in different organs with varying degrees of clinical relevance. Aim of this study was to determine the amount of particles infused to a patient during a long-term treatment under different failure conditions of the filter.


METHODS
The filters were prepared by cutting single hollow fibers. Fresh-frozen plasma (FFP) and a mixture of glycerol and water were used as a medium together with microparticles potentially used in the MDS. The amounts of particles transferred from the filtrate into the primary circuit were measured.


RESULTS
The analysis of particle transfer in the case of a single cut hollow fiber inside the membrane results in particle volumes of up to 26 ml calculated for 10 h.


CONCLUSIONS
Particle leakage in microparticle suspension based detoxification systems can lead to considerable particle transfer to the patient. Therefore, a particle detection unit which is able to detect critical amounts of particles (<1 ml particle volume/treatment) in the extracorporeal blood line is necessary for patient safety.
Hartmann
Jens
J
Center for Biomedical Technology, Danube University Krems, Krems, Austria. jens.hartmann@donau-uni.ac.at
Schildboeck
Claudia
C
Brandl
Martin
M
Falkenhagen
Dieter
D
D005112:Extracorporeal Circulation / Q000009:adverse effects*; D005374:Filtration / Q000295:instrumentation*; D006801:Humans; D008863:Microspheres; D010316:Particle Size; D016060:Sorption Detoxification / Q000009:adverse effects / Q000379:methods*