Effects of Individualized Dialysate Sodium in Hemodialysis
Author(s): Kawin Gunasekaran, E Ramprasad Elumalai, M Jayakumar and Manikantan Sekar*
Abstract
Sodium is the major extracellular cation in the body and hence and is the major determinant of extracellular fluid (ECF) content and serum osmolarity. Volume overload contributed by increased sodium is a major problem in patients on hemodialysis (HD). Sodium entry occurs in hemodialysis patients from dietary intake, dialysis fluid or from saline infusions given during the hemodialysis session. Currently, all patients undergoing maintenance hemodialysis in our centre and hospitals world-wide are dialysed with dialysate sodium of 138 meq/L and this dialysate sodium level used as a standard value in all patients irrespective of their blood sodium values. Patients undergoing dialysis have an individualized sodium and osmolarity value which are known as sodium and osmolar set point . respectively, and are unique for each patient and is highly conserved. A higher dialysate sodium concentration more than the patient’s plasma sodium level will cause sodium gain during dialysis and increase the total body sodium. This promotes interdialytic fluid ingestion in order to restore an individual’s sodium and osmolar set point. These patients might be actually having a lower sodium set point and if so, with each hemodialysis session, more sodium is continuously being added to their body, contributing to increased thirst, interdialytic weight gain (IDWG) and blood pressure. Long standing fluid overload can lead to uncontrolled hypertension, left ventricular hypertrophy and thus, lead to cardiovascular morbidity and mortality. Theoretically, it looks advantageous to use tailor made dialysate sodium to avoid addition of excess sodium to the body during hemodialysis sessions. Several studies have been done regarding the individualization of sodium prescription in HD patients, but the results have been inconsistent. There are very few studies from India regarding sodium set points in our HD population and by prescribing Individualized dialysate sodium prescription, co-morbidities mentioned above will be drastically reduced. Our aim was to investigate and study the beneficial effects of individualized sodium profiling on patients undergoing dialysis.