VIII
- High blood pressure and special cases
8.1
- High blood pressure and sport
8.2
- High blood pressure and obesity
8.3 - High
blood pressure and pregnancy
8.4
- High blood pressure and elderly
8.5
- High blood pressure and children
8.6
- High blood pressure and contraception
8.7
- Influence of hormones on high blood pressure (case of the post-menopausal
woman)
8.8 - Influence
of life style modification on blood pressure
8.3-
High blood pressure and pregnancy
The existence of a high blood pressure during the pregnancy
represents a real danger for the mother and the child, because it is integrated
in a disease that the physicians call "pre-eclampsia" or "eclampsia" according
to the stage. This disease is in fact an immunological disease responsible
for damage of the kidney, brain, liver, placenta, cardiovascular system and
hormonal system.
This disease appears during
the third quarter of a first pregnancy and disappears just after the
childbirth. It endangers the life of the mother and her baby, and often
causes premature births.
8.3.1- Symptoms
The symptoms are characterized
by diffuse oedemas (due to a renal insufficiency), a high blood pressure
which can be very high, disorders of the nervous system which are associated
with a reduction of the sight, violent headaches (due to an oedema
or to bleedings in the brain).
8.3.2- Causes
Many researchers around the
world have studied «Eclampsia», and three hypotheses are
currently retained: this disease comes from the placenta; it comes
from the mother and especially from her environment; or this is a purely
genetic disease of the mother. But these are only hypotheses and research
is currently in hand.
We know that this disease
corresponds to a disorder state of the immune system, but its exact
cause is now unknown.
8.3.3- Complications
Pre-eclampsia is responsible
for an attack of:
- The kidney: development
of a renal insufficiency and of diffuse oedemas;
- The
brain: development of an oedema and of bleedings in the brain;
- The
liver: possible development of a liver insufficiency;
- The
placenta, which can be detached from the uterus and induce
the death of the baby.
8.3.4- What the physician
do in case of eclampsia or high blood pressure during the pregnancy?
Initially, he suspects the
diagnosis of eclampsia in case of a high blood pressure, especially
if it minimal (diastolic) is higher than 100 millimetres of mercury
(10). Then, the diagnosis is confirmed by a high protein concentration
in the urine.
Then, an antihypertensive
drug therapy is prescribed, but in a very careful way so that the blood
pressure does not drop too quickly because the blood flow would be
severely reduced in the placenta.
When the birth is imminent,
the practitioner gives antihypertensive drugs by intravenous way, but
if the birth is not imminent then tablets are prescribed so as to delay
the birth as much as possible.
What does the physician
in case of a high blood pressure already existing before the pregnancy?
The majority of women who
have high blood pressure before the pregnancy will slightly increase
the value of their blood pressure and the cardiovascular risk is thus
weak. In general, the blood pressure will naturally decrease during
the second quarter of the pregnancy, because of a expansion of the
peripheral arteries. Thus, the antihypertensive drug therapy can be
stopped on this occasion, under strict medical supervision.
When the diastolic blood
pressure (the minimal one) drops below 90 millimetres of mercury (9),
the antihypertensive drug therapy can be reduced.
In this case, no medical
study has proved the real effectiveness of an antihypertensive drug
therapy on the cardiovascular complications.
To avoid high blood pressure,
it is of primary importance to respect life style modifications: that
is, the reduction of sodium intake and of high calorie meals. On the
other hand, it is not recommended during this period to lose weight
or to practise physical exercise.
The practice of self-measurement
of the blood pressure at home seems to be a very good way to prevent
cardiovascular complications.
If antihypertensive drugs
must be used, the practitioner must be careful and ensure of the absence
of toxicity on the child. The safer antihypertensive drugs are beta-blockers
firstly and the calcium-channel antagonists, secondly. All the other
antihypertensive drugs must be avoided.
File
last reviewed on : 18 dec 2011 |
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