Changes in auditory P3 event-related potentials in uremic patients undergoing haemodialysis.

A study on event-related P300 potential (ERPs) was performed in 20 patients suffering from chronic uraemia and undergoing haemodialysis in order to assessing the functioning of their cognitive processes. The patients were evaluated before and after a standard treatment of haemodialysis. The P300 potential was studied by means of the "oddball" paradigm and the acoustic modality. Moreover the patients' performance was assessed on the basis of the following psychological tests: the Mini Mental Test, the Number Connection Test and the Digit Span of the Wechsler Adult Intelligence Scale. A significant improvement in the P3 latency was demonstrated following the dialysis treatment. Even though a slight improvement in the N2-P3 deflexion amplitude was recorded after dialysis, it was not statistically significant. These data indicate a positive modification in the speed of the cortical function as a consequence of dialysis. These results suggest that the P3 latency obtained from auditory stimuli can help to assess the benefits obtained through extracorporeal dialysis, especially in the follow-up to the illness.