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How Long Before Having EMG Test Should One Stop Taking Lovenox?
Question: I am on lovenox shots 2 times daily 60ml for a blood clotting gene bc I've had PEs.
My neurologist wants to do an EMG but says I cannot on blood thinner. I would like from a hemotologist opinion if I stop lovenox may I do the test or is that too much of a risk and if I can stop Lovenox how long should I stop before EMG and when may I start back shots after EMG. Thanks
My neurologist wants to do an EMG but says I cannot on blood thinner. I would like from a hemotologist opinion if I stop lovenox may I do the test or is that too much of a risk and if I can stop Lovenox how long should I stop before EMG and when may I start back shots after EMG. Thanks
Brief Answer:
the risk is not clear
Detailed Answer:
Hello,
first of all the risk regarding the pulmonary embolism depends. If there was a clear cause of this PE like using contraceptives, smoking and having a surgery then the risk is not that high unless the PE is very recent. If the PE was sudden (which may indicate that you have thrombophilia that is a tendency to form clots) then the risk is much higher. A very recent PE makes the risk high anyway. More than 6 months after the event makes it much less likely.
The risk for muscle hematoma after an EMG in patients taking anticoagulants is not very clear. Some studies have failed to show increased risk (like these two: http://www.ncbi.nlm.nih.gov/pubmed/0000 and http://www.ncbi.nlm.nih.gov/pubmed/0000). If your neurologist wants to be more on the safe side regarding the hematoma then stopping lovenox 24 hours before the procedure is enough since the drug's half life is 4.5 hours. As soon as the procedure has finished the anticoagulation can be initiated again, provided that a hematoma has not formed already.
Kind Regards!
the risk is not clear
Detailed Answer:
Hello,
first of all the risk regarding the pulmonary embolism depends. If there was a clear cause of this PE like using contraceptives, smoking and having a surgery then the risk is not that high unless the PE is very recent. If the PE was sudden (which may indicate that you have thrombophilia that is a tendency to form clots) then the risk is much higher. A very recent PE makes the risk high anyway. More than 6 months after the event makes it much less likely.
The risk for muscle hematoma after an EMG in patients taking anticoagulants is not very clear. Some studies have failed to show increased risk (like these two: http://www.ncbi.nlm.nih.gov/pubmed/0000 and http://www.ncbi.nlm.nih.gov/pubmed/0000). If your neurologist wants to be more on the safe side regarding the hematoma then stopping lovenox 24 hours before the procedure is enough since the drug's half life is 4.5 hours. As soon as the procedure has finished the anticoagulation can be initiated again, provided that a hematoma has not formed already.
Kind Regards!
Above answer was peer-reviewed by :
Dr. Chakravarthy Mazumdar
I have a blood clotting gene. You said provided that a hematoma has not formed already. What do you mean by that sentence. Could you explain that more? If a hematoma has formed what are the consequences of that?
Brief Answer:
the test itself may cause a hematoma even if you're not taking the drug
Detailed Answer:
Of course...
A hematoma may form even if you're not on anticoagulants. So if you do the test, without being under the effect of the anticoagulant but a hematoma still forms, then taking the anticoagulant might impair the hematoma development, although the risk for PE is a much more serious one.
If you have a 'faulty' gene then you're in constant danger of thrombosis (depending on the gene). Some genes increase your risk only slightly. Other genes increase the risk a lot. Heterozygous Leiden positivity is case of slightly increased risk. Homozygous Leiden gene positivity leads to seriously increased risk for thrombosis. In patients with serious risk for thrombosis I usually recommend avoiding changes to their anticoagulant treatment, unless the procedure to be done is very invasive. The EMG is not such a procedure.
If a hematoma forms then there could be various problems from minor to very serious ones. A minor problem might be pain and some degree of disability. A serious problem could be a large hematoma and compartment syndrome, that is inadequate blood flow to the tissues and danger for serious damage to the area.
Kind Regards!
the test itself may cause a hematoma even if you're not taking the drug
Detailed Answer:
Of course...
A hematoma may form even if you're not on anticoagulants. So if you do the test, without being under the effect of the anticoagulant but a hematoma still forms, then taking the anticoagulant might impair the hematoma development, although the risk for PE is a much more serious one.
If you have a 'faulty' gene then you're in constant danger of thrombosis (depending on the gene). Some genes increase your risk only slightly. Other genes increase the risk a lot. Heterozygous Leiden positivity is case of slightly increased risk. Homozygous Leiden gene positivity leads to seriously increased risk for thrombosis. In patients with serious risk for thrombosis I usually recommend avoiding changes to their anticoagulant treatment, unless the procedure to be done is very invasive. The EMG is not such a procedure.
If a hematoma forms then there could be various problems from minor to very serious ones. A minor problem might be pain and some degree of disability. A serious problem could be a large hematoma and compartment syndrome, that is inadequate blood flow to the tissues and danger for serious damage to the area.
Kind Regards!
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Above answer was peer-reviewed by :
Dr. Chakravarthy Mazumdar
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