Effects of hydralazine on placental and renal circulation in pre-eclampsia.
BACKGROUND
Although hydralazine has been the drug of choice for treating pregnancy-induced hypertension for some time owing to its effect on peripheral vascular tonus, its effects on utero- and feto-placental circulation are less well understood.


METHODS
To evaluate the effect of hydralazine on placental circulation in cases of pre-eclampsia, Doppler ultrasonography was used to record blood velocity in the arcuate and umbilical arteries in 12 pregnancies complicated by pre-eclampsia, blood velocity in the maternal renal artery also being examined. The gravidae underwent Doppler ultrasonography after 24 hours bedrest in hospital (baseline values), and again 24 and 72 hours after starting oral hydralazine treatment at doses of 50 mg twice daily.


RESULTS
The gravidae showed increased heart rate and decreased blood pressure in response to treatment, but neither placental nor maternal renal blood velocity waveforms were affected.


CONCLUSIONS
The results suggest that at recommended oral doses hydralazine has no effect on placental or maternal renal vascular resistance.
Gudmundsson
S
S
Department of Obstetrics and Gynaecology, University of Lund, Malmö University Hospital, Sweden.
Gennser
G
G
Marsal
K
K
D000328:Adult; D001724:Birth Weight; D001775:Blood Circulation; D001783:Blood Flow Velocity / Q000187:drug effects; D001794:Blood Pressure / Q000187:drug effects; D004341:Drug Evaluation; D005260:Female; D005331:Fetomaternal Transfusion; D005865:Gestational Age; D006339:Heart Rate / Q000187:drug effects; D006801:Humans; D006830:Hydralazine / Q000008:administration & dosage* / Q000494:pharmacology; D006973:Hypertension / Q000188:drug therapy; D007231:Infant, Newborn; D007668:Kidney / Q000098:blood supply; D011225:Pre-Eclampsia / Q000000981:diagnostic imaging*; D011247:Pregnancy; D011249:Pregnancy Complications, Cardiovascular / Q000188:drug therapy; D011263:Pregnancy Trimester, Third; D012077:Renal Artery / Q000187:drug effects; D015203:Reproducibility of Results; D018608:Ultrasonography, Doppler; D016216:Ultrasonography, Prenatal; D014469:Umbilical Arteries / Q000187:drug effects
D006830:Hydralazine