Clinical control study of dialysates with different concentrations of calcium on blood pressure in patients under hemodialysis for prolonged period

OBJECTIVE: To investigate the changes in blood pressure in hemodialysis patients treated with low calcium dialysate or high calcium dialysate for long time. METHODS: Fifteen patients undergoing hemodialysis were enrolled in this study. High calcium dialysate (1.75 mmol/L, Dca1.75) was first used for 6 months, then low calcium dialysate (1.25 mmol/L, Dca1.25) was used for 6 months. Serum calcium, phosphate, blood urea nitrogen, and creatinine were measured, blood pressure was recorded before and after hemodialysis at the beginning, and also at 1, 2, 3 and 4 hours after hemodialysis. RESULTS: Compared with that before the treatment, systolic and diastolic blood pressure lowered significantly after single low calcium hemodialysis for 4 hours (both P 0.05), while systolic blood pressure rose during 6 months of hemodialysis with high calcium dialysate (P<0.05). Changes in systolic blood pressure were significantly different between two groups using dialysates with different calcium concentrations (P<0.05). CONCLUSION: Systolic blood pressure and incidence of hypertension decrease after single low calcium hemodialysis.