BASE-LINE SERUM AND CEREBROSPINAL-FLUID MAGNESIUM LEVELS IN NORMAL-PREGNANCY AND PREECLAMPSIA

Objective: To determine whether baseline cerebrospinal fluid magnesium levels in preeclampsia differ from those in normal pregnancy, and to ascertain whether pre-treatment cerebrospinal fluid magnesium levels c orrelate with serum levels, which would suggest a baseline alteration in the blood-brain barrier in preeclampsia. Methods: When spinal analg esia or anesthesia was administered for delivery, serum and cerebrospi nal fluid magnesium levels were determined in 20 normal gravidas and 2 0 preeclamptic women not treated with magnesium sulfate. Data were ana lyzed by two-sided Student t test and regression analysis. Results: Me an (+/- standard deviation) cerebrospinal fluid magnesium level for pr eeclamptic patients was 2.23 +/- 0.09 mEq/L, which was not significant ly different from controls. Regression analysis revealed no significan t correlation between cerebrospinal fluid and serum magnesium levels f or either normal or preeclamptic gravidas. Conclusion: During the thir d trimester, there is no difference in baseline, pre-treatment cerebro spinal fluid magnesium levels in preeclamptic patients compared to nor mal subjects, and no correlation between cerebrospinal fluid and serum magnesium over the range of baseline values.