Intradialytic changes of serum magnesium and their relation to hypotensive episodes in hemodialysis patients on different dialysates

Abstract

Magnesium is a crucial mineral, involved in many important physiological processes. Magnesium plays a role of maintaining myocardial electrical stability in hemodialysis patients. Intradialytic hypotension is a common complication of dialysis and it is more common with acetate dialysate. The significance of the intradialytic changes of magnesium and their relation to parathyroid hormone (PTH) level and calcium changes during dialysis, and their relation to hypotensive episodes during dialysis are interesting. The aim of this work is to investigate the intradialytic changes of serum magnesium in chronic hemodialysis patients with different hemodialysis modalities and the relation to other electrolytes and to PTH, and also the relation to intradialytic hypotension. The present study was conducted on 20 chronic renal failure patients. All patients were on regular hemodialysis thrice weekly 4 hr each using acetate dialysate (group I). To study the effect of an acetate-based dialysate vs. a bicarbonate-based dialysate on acute changes of magnesium, calcium, phosphorus, and PTH during a hemodialysis session, the same patients were shifted to bicarbonate dialysis (group II). All patients were subjected to full history and clinical examination, predialysis laboratory assessment of blood urea nitrogen (BUN), serum creatinine, albumin, and hemoglobin, serial assessment of magnesium, calcium, phosphorus, and parathyroid hormone at the start of the hemodialysis session, 2 hr later, and at the end of the session, blood pH, and electrocardiogram (ECG) presession and postsession. All patients were urged to fix their dry weight, diet, and current medications. None of the patients had diabetes, neoplasia, liver disease, or cachexia, nor had they been recently on magnesium-containing drugs or previously parathyroidectomized. Hemodialysis sessions were performed by volumetric dialysis machines using the same electrolyte composition. Magnesium level significantly increased in the bicarbonate group at the end of dialysis (0 hr: 2.73+/-0.87, 2 hr: 3.21+/-1.1, and at 4 hr: 5.73+/-1.45 mg/dL, p value <0.01), while it significantly decreased in the acetate group (0 hr: 3.00+/-0.58, 2 hr: 2.26+/-0.39, 4 hr: 1.97+/-0.33 mg/dL, p value <0.01). Calcium level significantly increased in the bicarbonate group (p=0.024) but not in the acetate group. Phosphorus level significantly decreased in both acetate and bicarbonate groups. PTH level did not significantly change in either group, p value > or =0.05. Blood pH significantly increased, changing from acidic to alkaline pH, with both modalities of hemodialysis. ECG showed no significant changes during sessions with either type of dialysate. Hypotension was significantly higher in group I compared with group II (p=0.01), and this hypotension was positively correlated with a decrease in serum magnesium level in group I. Intradialytic changes in serum magnesium have no correlation with intradialytic changes in serum calcium or with PTH level. However, it was significantly correlated with hypotension...

Hypomagnesemia in Hemodialysis Patients: Role of Proton Pump Inhibitors

“…Over the long term, chronic hypomagnesemia can increase vascular calcification in hemodialysis patients [41,42]. In addition, there is concern about the potential hemodynamic and cardiovascular effects of acutely lowering the plasma magnesium level during hemodialysis [43,44]. Most importantly, serum magnesium has been recently reported to be a significant predictor of mortality in advanced renal disease patients [20,21,22,23].…”

Magnesium and Kidney Disease

“…These associations have been con fi rmed by more recent studies where the investigators reassured that intradialytic lowering in serum magnesium were signi fi cantly correlated with hypotension during the dialysis session [ 75,76 ] .…”

Impact of Abnormal Serum Electrolyte Levels and Acid-Base Disorders on Clinical Outcomes among Maintenance Hemodialysis Patients

“…OALib Journal Recent results have indicated that low intradialytic serum magnesium level was associated with hypotensive episodes during HD [36] [41] [42]. Also, ESRD patients with low serum magnesium level were observed to have a higher and faster rate of vascular calcification [43] [44] [45].…”

“…Magnesium (Mg) is mainly excreted through the renal system and HD patients may have a normal, increased or decreased level of serum magnesium [36].…”