Randomised study assessing the effect of phenytoin and magnesium sulphate on maternal cerebral circulation in eclampsia using transcranial Doppler ultrasound.
OBJECTIVE
To assess maternal middle cerebral artery flow velocity patterns as measured by transcranial Doppler ultrasound (TCD) in eclampsia and to investigate the effect of the anticonvulsants magnesium sulphate (MgSO4) and phenytoin on cerebral circulation.


METHODS
Prospective randomised study.


METHODS
High care obstetric unit, King Edward VIII Hospital, Durban, South Africa.


METHODS
Twenty-four eclamptic patients: 13 received MgSO4 and 11 phenytoin.


METHODS
Middle cerebral artery flow velocity waveforms were measured using 2 MHz pulsed Doppler ultrasound via the transtemporal approach in eclamptic patients, before and 15 minutes after the loading dose of anticonvulsant.


RESULTS
Magnesium sulphate significantly reduced the pulsatility index (P = 0.002) and mean flow velocity (P = 0.02) in the middle cerebral artery, whereas phenytoin failed to produce any statistically significant effect. However, differences between groups were not statistically significant. Systolic and diastolic blood pressures were reduced in both the MgSO4 and phenytoin groups.


CONCLUSIONS
These findings provide firm evidence that MgSO4 relieves cerebral vasospasm, compared with phenytoin, and may therefore be the better drug for the prevention of eclamptic convulsion.
Naidu
S
S
MRC/UN Pregnancy Hypertension Research Unit, University of Natal, Faculty of Medicine, Congella, South Africa.
Payne
A J
AJ
Moodley
J
J
Hoffmann
M
M
Gouws
E
E
D000293:Adolescent; D000328:Adult; D000927:Anticonvulsants / Q000627:therapeutic use*; D001783:Blood Flow Velocity; D001794:Blood Pressure / Q000187:drug effects; D002536:Cerebral Arteries / Q000000981:diagnostic imaging / Q000503:physiopathology; D002560:Cerebrovascular Circulation / Q000187:drug effects*; D004461:Eclampsia / Q000503:physiopathology / Q000517:prevention & control*; D005260:Female; D006801:Humans; D008278:Magnesium Sulfate / Q000627:therapeutic use*; D010672:Phenytoin / Q000627:therapeutic use*; D011247:Pregnancy; D011446:Prospective Studies; D017585:Ultrasonography, Doppler, Transcranial; D018084:Ultrasonography, Interventional
D000927:Anticonvulsants; D010672:Phenytoin; D008278:Magnesium Sulfate