Measuring haemolysis in haemodialysis: Comparison between a new and existing data processing algorithms

Acute haemolysis in haemodialysis is a relatively rare complication, but it can lead to life-threatening issues up to the death of the patient. Due to the lack of measurement methods able to provide a realtime and in-line measurement of the haemolysis in extracorporeal circulation, in current medical practice the haemolysis level is not monitored during haemodialysis. In last two years we proposed a measurement method capable to measure in-line and in real-time the haemolysis level during haemodialysis. Such method is based on the estimation of the filter permeability to haemoglobin. To estimate the filter permeability we proposed two data processing algorithms: one simplified algorithm supposing constant permeability and the other supposing the filter permeability to be a linear function of the time integral of the filtered volume of solvent. However, the constant permeability algorithm is reasonably prone to errors, whereas the algorithm based on the time integral of the solvent volume does not allow the integration of the developed measuring system with hemodialyzers already in use. To overcome such limitation, in this paper we propose a new data processing algorithm based on the time integral of the mass of filtered haemoglobin. Such quantity can be easily estimated by the measuring system, allowing straightforward integration with hemodialyzers already in use. The performed experimental activities indicate as the new data processing algorithm is reasonably able to provide performance equal or better than the previous data processing algorithms