الفهرس 
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Abstract
Summary
Pulmonary hypertension is defined as an increase in
mean pulmonary arterial pressure (mPAP) ≥25 mmHg at rest
as assessed by right heart catheterization. Pulmonary
hypertension is a rare disorder that can be present in women of
child-bearing age. During pregnancy, It is associated with high
morbidity and mortality in all defined clinical groups of
pulmonary hypertension. Therefore, pulmonary hypertension
is regarded a contraindication for pregnancy. However,
sometimes women become pregnant despite being advised
against pregnancy, or pulmonary hypertension is newly
diagnosed during pregnancy. These women are usually
advised to terminate the pregnancy even though termination
itself is also associated with maternal risks. Some women do
not regard termination as an acceptable option and carry on
with their pregnancy.
The normal physiological changes of pregnancy are
poorly tolerated by women with pulmonary hypertension.
Pregnancy is associated with increased plasma volume and
decreased systemic vascular resistance, both resulting in an
increase in cardiac output. Fatigue and exertional dyspnoea are
Intensive Care Management of Pulmonary Hypertension With Pregnancy
Summary 53
the most frequent presenting symptoms. They are due to
reduced cardiac output and impaired oxygen transport. Chest
pain is often present and reflects right ventricular ischemia.
Syncope can result from low cardiac output. Several signs of
right heart failure, such as hepatomegaly, ascites, and ankle
edema, may be hard to identify during pregnancy or resemble
normal pregnancy.
Elevated jugular venous pressure and a loud pulmonary
component of the second heart sound are useful signs that
point to the diagnosis. Echocardiography will usually reveal
the diagnosis. The threshold to perform echocardiography
should be low during pregnancy in women with dyspnea.
Right heart catheterization is required to confirm the diagnosis
and gives useful additional information on pulmonary vascular
resistance and cardiac output. It can be performed with
relatively low fetal risk since radiation can be avoided. During
pregnancy, it should be reserved for women in whom the
results have therapeutic consequences, because of the
associated risks of thromboembolism and infection. Functional
capacity needs to be evaluated (New York Heart Association
or World Health Organization functional class) and exercise
capacity can be assessed with an un-encouraged six-minute
walking test.
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Summary 54
When pregnancy occurs, termination should be offered
even if the woman is in a good clinical condition. Pregnancy
termination is a high-risk procedure and it should be
performed in an experienced centre. When the woman chooses
to continue pregnancy, it is important that she is managed by a
multidisciplinary team in a centre licensed for the treatment of
pulmonary hypertension patients. The team should include a
pulmonary hypertension specialist, a cardiologist, obstetrician
and anesthetist specialized in managing high risk pregnancies,
and a neonatologist. The woman must be followed at least
monthly. The cardiac demands should be minimized by rest
and a low salt diet. To avoid caval vein compression, the
patient should lie in the lateral position. Hospital admission in
the second trimester is often advised, though its benefit is
unproven and a satisfactory outcome of pregnancy has been
described when women were followed on an outpatient basis.
Oxygen should be given when hypoxemia is present.
Anticoagulation therapy should be continued when there is an
established indication outside pregnancy. It should, however,
be considered on an individual basis in other women, since
there may be bleeding risk, for example in women with
Eisenmenger syndrome or portal hypertension. When
therapeutic anticoagulation therapy is given, it is mandatory
that the anticoagulation effect is monitored carefully and
Intensive Care Management of Pulmonary Hypertension With Pregnancy
Summary 55
frequently, since dose requirements change during pregnancy
with increase in plasma volume and glomerular filtration rate.
When heart failure occurs, diuretics are the appropriate
therapy, preferably furosemide. Spironolactone is contraindicated
because of anti-androgenic effects. PAH-specific
therapy includes Calcium channel blockers, epoprostenol,
iloprost, treprostinil and phosphodiesterase type-5 inhibitors.
On the management of pregnant women with heart
disease ,it is advised that women who are on drug therapy for
pulmonary hypertension continue this therapy during
pregnancy. Since bosentan has teratogenic effects, patients
should be informed about the fetal risks, and substitution with
other targeted drugs is often advised. It is probably beneficial
to start advanced therapy with prostacyclin analogues or
sildenafil early during pregnancy.
A timely delivery plan should be constructed and be
available to all team members. The best mode of delivery is a
matter of debate. Vaginal delivery is associated with volume
changes during contractions which poses a problem in women
with pulmonary hypertension since they have limited
capability to increase their cardiac output. Moreover, pushing
can have adverse hemodynamic effects. Planned cesarean
delivery may therefore be a better choice, though vaginal
Intensive Care Management of Pulmonary Hypertension With Pregnancy
Summary 56
delivery is not considered absolutely contraindicated. In many
cases, vaginal delivery will not be an option because early
delivery is often necessary. When cesarean section is
performed, general anesthesia has several disadvantages that
should be taken into account. These include cardiodepression
by volatile agents, and increase of pulmonary vascular
resistance during intubation and positive pressure ventilation.
A careful combined epidural and low-dose spinal anesthesia
avoids vasodilatation. It can be safely applied by an
experienced anesthetist and is probably the best option. During
delivery, hemodynamic monitoring of arterial and central
venous pressure is advised. Pulmonary artery pressure
monitoring probably has more risks than advantages. Hospital
observation is necessary until at least 2 weeks after delivery.
Women with pulmonary hypertension should be advised
against pregnancy. Adequate contraception should be installed.
Barrier methods are safe but not sufficiently effective. Lowdose
combined oral contraceptives containing ethinyl estradiol
are not suitable for women with pulmonary hypertension since
they are thrombogenic.
Progesterone-only pills or dermal implants can be used.
Endothelin receptor antagonists such as bosentan can reduce
the efficacy of oral contraceptives. The levonorgestrelIntensive
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Summary 57
releasing intra-uterine device is very effective and safe.
Vasovagal reactions can, however, occur during implantation
and may be poorly tolerated; therefore, women with
pulmonary hypertension should have these devices implanted
in hospital.