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In summary, what is the role of bedside examination for the evaluation of DVT?
Still an important one. Although individual symptoms and signs are not, by themselves, very useful, a careful review of risk factors, symptoms, and signs may nonetheless help determine the pretest probability of disease. And thus, it can guide interpretation of noninvasive diagnostic tests. This rekindled value of clinical examination has in recent time led to the hypothesis that when pretest probability of disease and noninvasive tests of lower extremity veins are concordant, DVT can be effectively ruled in or ruled out, whereas when pretest probability of disease and non-invasive tests are discordant, further evaluation is necessary. This approach has led to the creation of a clinical prediction guide for the management of patients with suspected DVT. What should then be the approach to a patient with suspected DVT? Because of the low sensitivity and specificity of clinical exam, many authors have tried to either combine various signs and symptoms (like the Wells’ scoring system for DVT) or have recommended exclusive reliance on noninvasive tests. Still, five findings seem to be independ-ently and significantly associated with the presence of proximal DVT: (1) swelling below the knee, (2) swelling above the knee, (3) recent immobility, (4) cancer, and (5) fever. Overall, the sensitivity of a positive clinical examination (associated with the presence of one or more of these independent predictors) is 96%, although the specificity is still low (20%). The absence of any of these findings is associated with a less than 5% chance of proximal DVT. Conversely, the presence of two or more of these clinical findings is associated with a 46% chance of proximal DVT. How accurate is physical exam for DVT?
Not much. Given the previously discussed constraints, the sensitivity is only 60–88%, and the specificity 30– 72%. In fact, the only important signs of DVT are tenderness and swelling. Calf asymmetry <2 cm (when measured 5 cm below the tibial tuberositas) also is abnormal and, if new, argues for DVT until proven otherwise. What are the traditional physical findings of deep vein thrombosis (DVT)? How valuable are they?10/28/2019 What are the traditional physical finding of DVT? How valuable are they? Based on traditional teaching, the physical exam of patients with suspected DVT should include: (1) careful inspection of the leg (looking for pitting edema, warmth, dilated superficial veins, and erythema); (2) measurement of leg circumference; (3) appreciation of a palpable cord; and (4) elicitation of Homans’ sign (development of calf pain following the forceful and abrupt dorsi-flexion of the foot). Yet, all these signs/maneuvers are quite inaccurate. Tenderness, swelling, warmth, and redness of the limb cannot adequately separate patients with or without DVT. In fact, warmth and color of the skin reflect superficial, rather than deep, circulation. A “palpable cord” is also indicative of superficial thrombophlebitis—which has no relationship to the deep vein system. Finally, skin changes, pitting edema, and dilated superficial veins may all be caused by other processes, such as venous insufficiency, leg trauma, cellulitis, obstructive lymphadenopathy, superficial venous thrombosis, postphlebitic syndrome, or a Baker (popliteal) cyst—a distended gastrocnemius-semimembranosus bursa that has ruptured into the calf, thus creating a perimalleolar crescent-shaped ecchymosis (pseudothrombophlebitis). And as for Homans’ sign, it has a low sensitivity and poor specificity. What is the role of physical exam for diagnosing DVT?
It is part of a comprehensive approach, including review of risk factors and symptoms. Commonly reported symptoms in suspected DVT include leg pain and swelling. Risk factors include instead immobility, paralysis, recent surgery, and/or trauma, malignancy, cancer chemotherapy, advancing age (i.e., >60 years), family history of thromboembolism, pregnancy, and estrogen use. In 50% of DVT patients, a major risk factor is present. Some of these are major, whereas others are minor. These can then be used to calculate the likelihood of disease What is the role of palpation in assessing varicose veins of the saphenous system?
It can provide confirmation of the presence of incompetent valves. To do so, place the fingers of one hand over the engorged saphenous vein (below the knee) while at the same time tapping gently with the other hand the same vein a foot cephalad (above the knee). Valve incompetence results in transmission of the impulse downward and backwards. |