A 74-year-old woman comes to the office for evaluation of increasing lower extremity swelling. The patient has a history of hypertension, obstructive sleep apnea, and mild, chronic lower extremity edema for several years. She reports "increased swelling and throbbing pain in my right leg" over the last 3 days. BMI is 40 kg/m2. She takes hydrochlorothiazide and lisinopril and uses continuous positive airway pressure at nighttime. Temperature is 36.5 C (97.7 F), blood pressure is 154/92 mm Hg, pulse is 76/min and regular, and respirations are 17/min. The patient is in no acute distress. Jugular venous pressure is elevated. The lungs are clear to auscultation. A loud P2 is present. There is 3+ edema in the right leg and 1+ edema in the left leg. There is no warmth, erythema, or tenderness to palpation of the lower extremities. Distal pulses are normal. Which of the following is the most appropriate next step in management?
Causes of lower extremity edema | |
Typically unilateral |
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Typically bilateral |
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This patient with acute right leg pain has asymmetric lower extremity edema (right > left) that is concerning for deep vein thrombosis (DVT). DVT should be suspected in patients with acute unilateral edema, which may be accompanied by pain (as in this patient); warmth, erythema, or tenderness to palpation may be present but are not specific. The presentation may be subtle. The most reliable and possibly the only finding of DVT is increased circumference of the affected leg due to localized edema, resulting from increased venous hydrostatic pressure distal to the thrombus and inflammatory disruption of vascular membrane integrity.
Patients with suspected DVT should undergo Doppler ultrasonography of the legs to confirm the diagnosis. Treatment of DVT in most patients consists of anticoagulation (eg, factor Xa inhibitor). In patients with normal Doppler ultrasonography findings, an investigation of other potential causes of edema should be performed, including the following:
(Choice B) Pulmonary hypertension from OSA can cause leg edema and elevated jugular venous distension. However, asymmetric leg edema and pain alone would not be explained by OSA and do not warrant an evaluation of continuous positive airway pressure (CPAP) settings. CPAP settings should be evaluated in patients with refractory symptoms of OSA, such as snoring and daytime sleepiness.
Educational objective:
Deep vein thrombosis typically causes unilateral lower extremity pain with tenderness, erythema, and/or edema. In some cases, a unilateral increase in leg circumference (resulting from localized edema) is the only finding. The diagnosis is made via Doppler ultrasonography of the legs.