Head CT before lovenox in cancer patients?

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Interpolfanclub

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Anyone getting head CTs on cancer patients before giving them lovenox for DVT/PE/USA? One of my attendings does it to look for asymptomatic mets to the brain before giving them lovenox. If they have a met do you not give them the lovenox?

Curious if anyone else head CTs cancer patients before lovenox. Thanks.

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Anyone getting head CTs on cancer patients before giving them lovenox for DVT/PE/USA? One of my attendings does it to look for asymptomatic mets to the brain before giving them lovenox. If they have a met do you not give them the lovenox?

Curious if anyone else head CTs cancer patients before lovenox. Thanks.

Nope. Unless you have neurologic findings to warrant it. This is about as intelligent as the "rectal exam on everyone before Plavix" that I heard from an attending.
 
Anyone getting head CTs on cancer patients before giving them lovenox for DVT/PE/USA? One of my attendings does it to look for asymptomatic mets to the brain before giving them lovenox. If they have a met do you not give them the lovenox?

Curious if anyone else head CTs cancer patients before lovenox. Thanks.


Long story short - all cancer is not created equal. Certain brain metastases, such as those with thyroid, renal cell, and choriocarcinoma have high rates of spontaneous intracranial hemorrhage. It would not be prudent to give these patients LMWH. I also would not rely on my neurologic exam to screen these patients for brain mets. In your run-of-the-mill leukemia, lung CA, etc., patient, this is unnecessary. In patients with known brain lesions, I usually make the decision in consultation with the patient's oncologist and/or neurosurgeon.
 
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This isn't crazy... this is good medicine!

I order Head CT's on cancer patients with newly diagnosed PE/DVT before anticoagulation if they have not had recent brain imaging (usually within the last month) regardless of any complaints or neuro findings. I think this is important as it could result in devastating consequences if the patient has asymptomatic mets and then receives blind anticoagulation.... These patients should really get IVC filters and not be anticoagulated. Additionally, what if your patient with a newly diagnosed DVT/PE decompensates or arrests in the ER ... or later in their hospital stay? Are you going to give that patient tPA??? I would rather know if they are a candidate for tPA up front. Once they code, it's too late to run them to the scanner....

If the head CT is negative for mets, I go ahead with anticoagulation.

If the head CT is positive for mets, I discuss it with a hematologist/oncologist before anticoagulation. I document my discussion including possibly withholding for IVC placement in the morning depending on type of cancer, size & number of mets, risk of ICH, and current hemodynamic status of the patient. And I inform the patient of the risk of intracranial hemorrhage with anticoagulation before intiating therapy, and make sure they are comfortable with this risk, and document that discussion as well.
 
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Not EMB, but from a case earlier in the month... Lung CA patient with a DVT came in for mental status changes three days after being started on Lovenox. You guessed it, big bleed. So I know there is no evidence on head CTs on everyone with cancer and a DVT, but I think I will in the future.
 
Anyone getting head CTs on cancer patients before giving them lovenox for DVT/PE/USA? One of my attendings does it to look for asymptomatic mets to the brain before giving them lovenox. If they have a met do you not give them the lovenox?

Curious if anyone else head CTs cancer patients before lovenox. Thanks.
Are you referring to prophylactic Lovenox or in cases of pre-established dx?
 
I just figured out what USA means... :D I personally don't do Head CT's before anticoagulation with Acute Coronary Syndrome. Here's my reasoning....

I find that I rarely anticoagulate UA unless they have dynamic EKG changes in the ER... and these patients need the cath lab anyway, so the heparin is only going to be short term and can be stopped/reversed rapidly. In the case of a cancer patient with no head complaint or neuro deficit, I would go ahead with the usual therapy. Of course, if they had known mets, I would probably discuss it with the cardiologist and hold anticoagulation and stress the need for cath immediately as medical therapy is not ideal.

In NSTEMI and STEMI, I wouldn't screen asymptomatic cancer patients with a head CT b/c anticoagulation is short term and their heart is much more likely to kill them than the small chance that short term anticoagulation will cause any significant ICH (presuming that the asymptomatic patient actually had an undiagnosed brain met in the first place)... again, I would discuss it with the cardiologist and push for the NSTEMI to get to the cath lab immediately.
 
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To clarify my above post, I only do the screening head CT with Lovenox for a DVT. If the patient needs the cath lab, I obviously go right away with heparin and aspirin.
 
It is more useful to document a normal neuro exam. The sensitivity for a non-contrast head CT for asymptomatic mets is well south of 100%, because unless there is already a hemorrhage or edema around the met (i.e. it's getting larger and more likely to be already symptomatic) many will be isodense to surrounding brain tissue and will be easily missed.

It is also unclear to me how finding a met without hemorrhage would change your management if you are starting anticoagulation for someone for a life-threatening thrombotic process like a PE. You need to discuss potential bleeding complications, including intracranial hemorrhage in any patient you anticoagulate anyway. IVC placement is a management option which is not immediately available (assuming the source of the PE is even infrarenal to begin with), and I think that withholding anticoagulation in what is already a high risk patient pending filter placement is much more risky than the remote possiblity of hemorrhage due to an asymptomatic met.

The only time I do the "double scan" (head + CTA thorax) is when the person has experienced head trauma in proximity to their presentation and I'm concerned about anticoagulating a fresh bleed.
 
In my experience, it is all dependent. For instance, recently had someone with PE with primary peritoneal cancer, negative PET scan in the last 6 months. Extremely low risk cancer for mets, plus negative recent scan, no need for CT.

However, I would certainly think about it in the setting of a cancer that is more classic for brain mets. Also, as others have posted, I always call their CA doc and see what their opinion is, and they know best the risk of mets.
 
I'm curious how many people posting on this thread would settle for a normal neuro exam to rule out the presence of intracranial metastatic disease, if the patient in the ER was your father/mother/sibling with lung cancer and a newly diagnosed PE. A Head CT takes 10 minutes and could save a patient from a devastating iatrogenic complication.

I know I wouldn't accept it a normal exam as ruling out brain mets. I would ask for a CT scan of the Head before anticoagulating one of my family members, and INSIST on it prior to administering tPA.
 
I know I wouldn't accept it a normal exam as ruling out brain mets.

If won't accept a normal exam to rule out mets, then you shouldn't accept a head CT, which is an insensitive test for intracranial metastasis.

There is disagreement even among neurologists and oncologists about whether to anticoagulate patients with intracranial mets. What data there is does not seem to indicate that the risk is extreme:

From Letai, 1999:

The risk of intracerebral hemorrhage, the main concern of most clinicians in anticoagulating patients with brain metastases, was 0%-5%. In general, bleeding complications occurred in the setting of supratherapeutic anticoagulation.

You have a Hobson's choice between a low risk of intracranial hemorrhage or a higher risk of death from PE.

Unstable angina is a softer indication. If you have someone who has an active GI or pulmonary primary, there are other risks of anticoagulation which are not addressed by the intracranial met issue which have to be weighed with the relative small potential benefit in this case. On the other hand, if have someone with a STEMI, would you withhold tPA or cath/stent/anticoagulation on the basis of a solitary asymptomatic met on CT? The ACC guidelines do not support this.
 
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