ECG-Based Monitoring of Electrolyte Fluctuations During the Long Interdialytic Interval

Abstract

Hemodialysis (HD) patients have a higher risk of sudden death due to cardiac arrhythmias, which commonly occur during the long interdialytic interval (LII) as a result of electrolyte fluctuations (EFs). Noninvasive monitoring of EFs would enable restoring normal serum electrolyte levels (SELs) by performing early HD before the onset of arrhythmias. In this study, we propose an ECG-derived descriptor, θ µ, that is noise robust and capable of capturing EFs during HD and the LII. To investigate the variation of θ µ, ECG and blood samples of 3 patients were acquired continuously, starting at Friday's HD and ending at Monday's HD. Results show that the increase of θ µ during Friday's HD is correlated with the decrease of SELs. Moreover, θ µ tends to decrease during the LII (no blood samples were obtained) and further increases during Monday's HD. If results in larger databases are confirmed, θ µ might be suitable for noninvasive monitoring of EFs during the LII.