Effects of a magnesium-free dialysate on magnesium metabolism during continuous ambulatory peritoneal dialysis.
While the use of magnesium-containing compounds is usually contraindicated in dialysis patients, the risk of toxicity from hypermagnesemia can be reduced by lowering the magnesium concentration in dialysate. We examined the effects of a magnesium-free dialysate on both serum magnesium level and the peritoneal removal rate of magnesium over 12 weeks in 25 stable patients undergoing continuous ambulatory peritoneal dialysis (CAPD). After 2 weeks, the serum magnesium level decreased from 2.2 to 1.9 mg/dL (0.9 to 0.8 mmol/L) (P less than .02) and the peritoneal removal rate increased from 66 to 83 mg/d (2.8 to 3.5 mmol/d) (P less than .05), with both values remaining stable thereafter. There was a strong association between these parameters (r = -0.62, P less than .05), suggesting that the serum magnesium level decreased as a result of the initial increased peritoneal removal rate. For an additional 4-week period, a subgroup of nine patients received magnesium-containing, phosphate binding agents instead of those containing only aluminum. During this phase, serum inorganic phosphorus was well controlled. The serum magnesium level increased only from 1.8 to 2.5 mg/dL (0.7 to 1.0 mmol/L) (P less than .05), due in great part to the concomitant 41% rise in peritoneal magnesium removal from 91 to 128 mg/d (3.8 to 5.3 mmol/d) (P less than .05). No toxicity was noted during the entire 16-week study period, nor did serum calcium change. Thus, serum magnesium levels remained within an acceptable range as magnesium-containing phosphate binders were given through the use of magnesium-free peritoneal dialysate.(ABSTRACT TRUNCATED AT 250 WORDS)
Shah
G M
GM
Nephrology Section (III N), VA Medical Center, Long Beach, CA 90822.
Winer
R L
RL
Cutler
R E
RE
Arieff
A I
AI
Goodman
W G
WG
Lacher
J W
JW
Schoenfeld
P Y
PY
Coburn
J W
JW
Horowitz
A M
AM
D000536:Aluminum Hydroxide / Q000627:therapeutic use; D002118:Calcium / Q000097:blood; D004338:Drug Combinations / Q000627:therapeutic use; D005260:Female; D006801:Humans; D008274:Magnesium / Q000008:administration & dosage / Q000378:metabolism*; D008276:Magnesium Hydroxide / Q000627:therapeutic use; D008297:Male; D008875:Middle Aged; D010531:Peritoneal Dialysis, Continuous Ambulatory; D010758:Phosphorus / Q000097:blood; D012841:Simethicone / Q000627:therapeutic use; D013997:Time Factors
D004338:Drug Combinations; C008570:aluminum hydroxide, magnesium hydroxide, simethicone drug combination; D010758:Phosphorus; D000536:Aluminum Hydroxide; C016545:magaldrate; D012841:Simethicone; D008274:Magnesium; D008276:Magnesium Hydroxide; D002118:Calcium