Placebo-controlled study of intravenous magnesium supplementation during large-volume leukapheresis in healthy allogeneic donors.
BACKGROUND
Marked decreases in ionized magnesium (iMg) levels occur during large-volume leukapheresis (LVL); however, the effect of intravenous (IV) magnesium supplementation in this setting has not been carefully studied.


METHODS
Thirty healthy allogeneic peripheral blood progenitor cell donors receiving citrate anticoagulant with IV calcium prophylaxis were randomized to receive either IV magnesium (0.2 mg Mg per mL acid citrate dextrose-A) or placebo during LVL, with a double-blind design.


RESULTS
Thirty subjects underwent 75 LVL pro- cedures, 37 with magnesium and 38 with placebo. Group characteristics were similar for sex, weight, citrate infusion rate (1.36 mg/kg/min vs. 1.37 mg/kg/min), and volume processed (16 L vs. 17 L). Serum iMg levels remained within the reference range with magnesium supplementation, but decreased 39+/-11 percent below baseline (p<10(-10)) after placebo, with greater decreases after consecutive procedures. Subjects receiving magnesium had more vigorous parathyroid hormone responses and higher glucose levels and also tended to have higher serum potassium and ionized calcium levels. Mild paresthesias, coldness, and nausea occurred in 28, 20, and 7 percent of donors, respectively, with no significant differences between groups. Severe symptoms (chest tightness) occurred in only one subject receiving placebo.


CONCLUSIONS
IV magnesium supplementation exerts a significant impact on serum magnesium levels, but does not reduce the frequency or severity of the relatively mild citrate-related effects observed in LVL performed with continuous IV calcium prophylaxis.
Haddad
Salim
S
Department of Transfusion Medicine, Warren Grant Magnuson Clinical Center, National Institutes of Health, Bethesda, Maryland, USA. salim.haddad@Fda.hhs.gov
Leitman
Susan F
SF
Wesley
Robert A
RA
Cecco
Stacey
S
Yau
Yu Ying
YY
Starling
Judith
J
Rehak
Nadja N
NN
Bolan
Charles D
CD
D000328:Adult; D000368:Aged; D000925:Anticoagulants / Q000009:adverse effects; D001782:Blood Donors; D001810:Blood Volume; D002118:Calcium / Q000008:administration & dosage / Q000097:blood / Q000493:pharmacokinetics / Q000652:urine; D019343:Citric Acid / Q000097:blood / Q000493:pharmacokinetics / Q000652:urine; D003404:Creatinine / Q000652:urine; D004311:Double-Blind Method; D005260:Female; D006801:Humans; D006863:Hydrogen-Ion Concentration; D007262:Infusions, Intravenous; D007937:Leukapheresis / Q000379:methods*; D008274:Magnesium / Q000008:administration & dosage* / Q000097:blood / Q000493:pharmacokinetics / Q000652:urine; D008297:Male; D008875:Middle Aged; D010281:Parathyroid Hormone / Q000097:blood; D010292:Paresthesia / Q000139:chemically induced; D010919:Placebos; D011188:Potassium / Q000097:blood; D011446:Prospective Studies; D012996:Solutions; D013997:Time Factors; D014184:Transplantation, Homologous
D000925:Anticoagulants; D010281:Parathyroid Hormone; D010919:Placebos; D012996:Solutions; D019343:Citric Acid; D003404:Creatinine; D008274:Magnesium; D011188:Potassium; D002118:Calcium