The effect of magnesium sulfate on maternal retinal blood flow in preeclampsia: a randomized placebo-controlled study.
OBJECTIVE
Our purpose was to determine the effect of a 6 gm intravenous bolus of magnesium sulfate on maternal retinal blood flow velocity waveforms in patients with preeclampsia.


METHODS
Twenty-two patients were randomized to two groups and were studied with color flow Doppler before and immediately after infusion of either 6 gm of magnesium sulfate or placebo. The central retinal and posterior ciliary arteries were studied.


RESULTS
Magnesium sulfate significantly reduced the pulsatility index (p < 0.005) in both vessels (change in pulsatility index = 0.26 +/- 0.23 for central retinal and -0.22 +/- 0.15 for posterior ciliary) when compared with placebo (change in pulsatility index = 0.02 +/- 0.10 for central retinal and -0.03 +/- 0.09 for posterior ciliary).


CONCLUSIONS
These data suggest that magnesium sulfate dilates the vessels distal to the central retinal and posterior ciliary arteries. Changes in pulsatility index in the retinal arteries may be indicative of similar changes in other cerebral vessels.
Belfort
M A
MA
Department of Obstetrics and Gynecology, Baylor College of Medicine, Houston, TX 77030.
Saade
G R
GR
Moise
K J
KJ
D000328:Adult; D001783:Blood Flow Velocity / Q000187:drug effects; D005260:Female; D006801:Humans; D008278:Magnesium Sulfate / Q000494:pharmacology*; D011225:Pre-Eclampsia / Q000503:physiopathology*; D011247:Pregnancy / Q000502:physiology*; D011674:Pulse / Q000187:drug effects; D012039:Regional Blood Flow / Q000187:drug effects; D012161:Retinal Artery / Q000000981:diagnostic imaging; D012171:Retinal Vessels / Q000000981:diagnostic imaging / Q000503:physiopathology*; D014463:Ultrasonography
D008278:Magnesium Sulfate