What sort of tests do doctors use to confirm the diagnosis of DVT?
In pregnancy, ultrasound is the first choice. However, while it is good for the thigh
vein thrombosis, it is not so accurate if the suspected site is the calf. For this,
a rather invasive method called venography may be used.
Even for a suspected calf vein thrombosis, the clinical impression, coupled with
ultrasound results, may be judged to be enough to start treatment. If venography
is used, the fetus will be shielded to minimize exposure to radiation - which is
low, to begin with.
Is the risk of pulmonary embolism the same, wherever the initial clot might be?
Of the two main areas commonly affected by thrombosis in the lower limb, the upper
inner thigh (femoral vein) thrombosis is potentially much more dangerous when compared
to the calf thrombosis.
While it is true that calf thrombosis rarely leads to pulmonary embolism, untreated,
the thrombosis in the vein could extend upwards into the thigh, thereby changing
the outlook dramatically.
Treatment for thrombosis in pregnancy
What is the treatment for thrombosis in pregnancy?
Once the diagnosis is established, treatment will be commenced immediately. The aim
is to prevent extension of the clot as well as embolism. It is also to allow the
existing clot to dissolve. Heparin (or its derivatives) is used in pregnancy. The
treatment is decided on the basis of the individual patient's circumstances. Generally,
in the medium term, the mother should expect to be on heparin injections daily.
The patient will be .taught to give herself the injections. The majority of patients
acquire the technique easily and quickly. Alternatively, a partner or another adult
may take up the task. Once all this is in place and her condition is stable, she
can attend hospital as an outpatient with regular and frequent reviews.
Are there any alternatives to heparin injections?
Until a few years ago, heparin had to be administered twice or three times daily.
Now, heparin derivatives are available, which are commonly known as low molecular-weight
heparins. These offer a distinct advantage to the traditional heparin in that they
are administered the same way but only once daily. Even though they are more expensive,
virtually all obstetric units have increasingly switched to these because of their
user-friendliness. They also seem to have milder side effects. They are just as effective
as traditional heparin.
There are some people who break into a cold sweat (literally!) at the mention of
the word "Injection". Is there no way around this?
Realistically - no. The other form of anticoagulation treatment, apart from heparin,
is warfarin. Warfarin is administered orally.
However, there is consensus now that warfarin is not safe to use in pregnancy. There
are quite a few abnormalities that have been associated with warfarin use during
pregnancy. It is also known that this may happen, at whatever stage of pregnancy
the treatment is used.
Abnormalities may include abnormal shape of the face, small head (microcephaly),
blindness or a missing spleen.
Even though all of these are uncommon, they are serious enough to make the use of
warfarin in pregnancy not worthwhile, particularly when an effective alternative
Pulmonary embolism in pregnancy
How can pulmonary embolism be recognized?
Pulmonary embolism essentially means a blood-clot lodging in a blood vessel within
the lungs. The lung section that is affected will then have its blood circulation
cut off. The symptoms that the individual will experience will depend on the actual
site of the blockage and the size of lung section affected.
Symptoms may range from non-specific ones including a cough, localized chest pain,
mild fever or coughing up thin blood-stained sputum.
When there is a major embolism, there could be sudden severe crashing chest pain,
shortness of breath and even passing out.