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Deep venous thrombosis (DVT) is a common condition for which clinical diagnosis is typically unreliable due to the infrequency of the classic findings of edema, warmth, erythema, pain, and tenderness, which are only present in 23 to 50 percent of patients. Failure to identify and treat deep venous thrombosis can lead to devastating results, including pulmonary embolism, superior vena cava syndrome, and associated complications up to and including death. However, empiric treatment with anticoagulation also comes with high-risk. Venogram remains the "gold standard" for the diagnosis of deep venous thrombosis. However, ultrasound is the most accurate non-invasive test to diagnose deep venous thrombosis. This activity reviews the ultrasonographic evaluation of deep venous thrombosis and highlights the role of the interprofessional team in managing patients with this condition. Objectives: Explain why it is important to diagnose a deep venous thrombosis. Review the clinically significant differences between an upper extremity deep venous thrombosis and a lower extremity deep venous thrombosis. Outline the methods for using an ultrasound examination to identify an upper extremity deep venous thrombosis versus a lower extremity deep venous thrombosis. Summarize the clinical impact that point of care ultrasonography can have on patient care and how the interprofessional team can evaluate and treat patients with deep venous thrombosis and improve outcomes. Access free multiple choice questions on this topic.

Deep venous thrombosis (DVT) is a common condition that appears in the emergency department and outpatient settings. Clinical diagnosis is unreliable due to the infrequency of the classic findings of edema, warmth, erythema, pain, and tenderness, which are present only in 23% to 50% of patients.[1] When a patient presents with findings consistent with DVT, it is important to make an accurate diagnosis, as the risk of failing to treat the condition involves pulmonary embolism (PE), superior vena cava syndrome (SVCS), and associated complications including death. However, empiric treatment with anticoagulation also comes with a high risk and cost to the patient. Venogram remains the "gold standard" for diagnosis of DVT. However, ultrasound is the most accurate non-invasive test to diagnose DVT. There are two main ways that ultrasound can be used to diagnose a DVT. The classic method is elective ultrasound performed by trained ultrasound technologist and read by radiology. Recently, a few studies have demonstrated that well-trained emergency and critical care physicians can complete bedside ultrasonography for lower extremity DVT with sensitivities and specificities of 95% and 96%, respectively.[2][3][4] If this is possible, this would significantly be able to improve emergency department throughput times for the most common type of DVT. Two-point compression has been widely accepted as a rapid way to assess for DVT in patients with a low pretest probability, making this an even more rapid way to assess for DVT than the complete assessment at the bedside.[5][6]

Ultrasound to identify DVT of the lower extremity can be performed either by an experienced emergency medicine physician, an ultrasound nurse/technician, or another physician with appropriate training for ultrasound utilization. Identification of DVT in the upper extremity has not been as thoroughly studied to determine the ability of other individuals besides ultrasound technicians to perform the examination.[7][8] Whoever performs the ultrasound to rule out DVT must know how to interpret the images. Missing a diagnosis of DVT can be associated with disastrous outcomes and possible litigation. If in doubt, always consult with a radiologist.

The nurse or nurse assistant can play an integral role in getting the patient prepared for the examination. The patient ideally needs to be in a hospital gown for either the upper extremity ultrasound evaluation or a lower extremity ultrasound evaluaion.  The nurse or nurse assistant can also assist with patient positioning during the exam, especially for the popliteal fossa evaluation. Special considerations may need to be made for patients who are unable to lay flat due. The bed may need to be adjusted to allow the patient to be supine while still keeping the head elevated. If the patient cannot lay supine, additional support will definitely be needed for positioning during the examination. A nurse or nurses assistant can also help workflow by having equipment ready at the bedside. The ultrasound machine needs to have the high frequency linear probe turned on and plenty of gel needs to be available. There should also be towels for wiping the patient off when the exam is complete and the appropriate wipes to clean the equipment.