Transfer to ED
One of my biggest pet peeves is transferring patients to the ER because of the inability to obtain confirmatory diagnostic testing for potentially serious conditions. We all know the ER cost of admission – 4-5 X what it costs to treat the same condition in the urgent care setting.
In part 2 of our discussion of deep vein thrombosis, we’ll focus on the appropriate management in the urgent care or occmed setting of patients with symptoms suspicious of DVT, but whom we may be able to avoid transfer to the ER.
The tricky part here is that often patients will exhibit mild or atypical symptoms when in fact they are suffering from DVT, while on the other hand, only about 25% of patients with symptoms suggesting DVT prove positive upon objective testing.
We’re not going into all the clinical manifestations of DVT here, this is well covered by an excellent article by Sabrina Sood, MD in the June, 2014 edition of JUCM. The quick and dirty version for practical management is to first understand that symptoms of unilateral pain, swelling and redness characteristic of DVT are likewise common with less serious conditions like cellulitis, Baker’s cyst, and superficial thrombophlebitis.
Wells Criteria
Use of the clinical model described by Wells et al can stratify patients into low or moderate-high-risk groups. If possible, have a version of this criterion built into your EMR so it is available to clinicians at the point of care and time isn’t lost hunting it down.
A further iteration of the model simply states “DVT likely” if > 1, and “DVT unlikely” if < 1.
A combination of Risk scoring, ultrasound, and D-dimer testing then guides further evaluation and treatment.
DVT Likely
When DVT is likely, referral for venous ultrasound is the next step. Your friendly neighborhood imaging center should be available to perform this on a “stat” outpatient basis without having to send the patient to the ER.
If the ultrasound is positive, anticoagulation is started. Combine a negative ultrasound with a negative D-dimer and DVT can be effectively ruled out with no further testing required.
A negative ultrasound with a positive D-Dimer requires serial ultrasounds (usually every 5-7 days) to confirm or rule out DVT.
Obviously, you need to check with your lab to see about the availability of stat pick up for this test, OR send the patient to the lab drawing station if that’s faster – you need these results within 2-3 hours.
DVT Unlikely
When DVT is unlikely, a D-dimer test is performed instead of sending the patient to the ER or for imaging. A negative test safely rules out DVT, avoiding up to 40% of ultrasounds performed on those suspected of having DVT. A positive D-dimer requires ultrasound follow-up.
Again, there is much more discussion to be had regarding alternative diagnoses, when to
consider venography vs ultrasound, empiric anticoagulation pending studies, etc.
But our purpose here is to avoid the sometimes “knee-jerk” tendency to send any potentially serious case to the ER and use clinical tools such as this to avoid not only the long wait in the ER but also the unneeded expense of some diagnostic studies.
The only time this should be necessary is when you have a “DVT likely” who comes in after hours or on weekends when imaging is not otherwise available.
Getting as many clinical decision support tools into your EMR so they are available at the point of care is a great way to improve the quality of care, reduce costs, and save valuable provider time looking up reference material.
