Book of Medical Disorders in Pregnancy - Tintash

intensive care room for the next 48
hours.
Magnesium sulfate:
Activity - The action of magnesium
sulfate is primarily at the neuromuscular
junction, causing a reduction in liberated
acetylcholine and reducing muscle fibre
excitability. Its use is also associated
with occasional reduction in arterial
pressure. This slight lowering of peripheral
vascular resistance is due either to
peripheral vasodilation or secondary to
high initial magnesium concentrations in
the vasomotor center of the brain.
Increases in renal and uterine blood flow
have been reported. Therapeutic plasma
levels of 6 to 8m eq/L are recommended
for prevention of seizure activity.
Adequate monitoring to prevent magnesium
intoxication should include frequent
evaluation of deep tendon reflexes,
respiratory rate and urinary output.
Magnesium sulfate is cleared by the
kidneys and excreted unchanged in the
urine. Maternal side effects include
depressed myometrial and cardio-respiratory
activity. Confusion and agitation
may also occur. The woman's confusion
and agitation when she regains
consciousness can be minimized by
having a member of the immediate
family at the bedside and by avoiding
bright light, loud noises and number of
people in the room. If respiratory
depression develops, 10 ml of a 10 per
cent solution of calcium gluconate may
be given intravenously over 3 minutes.
Fetal side effects are negligible, though
some newborns may initially show some
degree of hypotonia.
Prognosis - This is potentially a serious
condition. Considerably increased maternal
and fetal mortality is associated with
63
this complication. Maternal mortality
associated with these complications has
fallen markedly from 52.2 per 100,000
live births in 1940 to 6.2 per 100,000 in
1970. The change is attributable to improved
antepartum care, early detection,
and aggressive management. Other factors
of general health, nutrition and
socio-economic status for the gravid
population at large, have also played a
major role. The incidence of both preeclampsia
and eclampsia in this country
has remained high in spite of
improvement in the nutritional status of
masses. This sad state of affairs reflects
the failure of both Government and
private agencies such as population
planning, maternal and child health
welfare organizations and a couple of
societies of obstetricians and gynecologists
of this country to introduce
adequate antenatal screening in this
country.
Management options:
Pre pregnancy:
Establish the etiology, if possible, and
the severity of the hypertension.
Evaluate renal function. The patient with
mild to moderate disease should be taken
off antihypertensive medication or
switched to medication known to have
few fetal side effects. Patients difficult to
control with severe diseases may need to
remain on pre-pregnancy medications,
despite potential fetal risks. Encourage
early prenatal care in an appropriate
setting.
Prenatal: Early and frequent prenatal
care is crucial to optimize maternal and
fetal outcome, Antihypertensive
medication can be discontinued, unless
the maternal, diastolic pressure exceeds
100-110 mmHg. Oral medications