Show Segments ABOUT EPISODES CRIBSIDERS DIGEST CME TOP PICKS CONTACT Search terms Intro, disclaimer TEACH Picks of the Week* The case of Lynn Fedema Pathophysiology of edema Differential diagnosis of chronic edema Chronic edema work-up Management of chronic edema Calvin Fedema and acute edema Evaluation of acute edema Outro Edema Pearls 1. The pathophysiology behind edema is an imbalance between oncotic pressure and hydrostatic pressure within the venous system. 2. Chronic venous insufficiency is the most common cause of chronic lower extremity edema, especially in older patients. 3. Again, bilateral lower extremity cellulitis is extremely uncommon. 4. Edema may be a sign cardiopulmonary, renal, hepatic, or thyroid dysfunction – so look at the patient in front of you and evaluate for risk factors. Find 5. Lymphedema results from impairment of lymphatic return, and can sometimes be distinguished from other causes of edema by ABOUT EPISODES CRIBSIDERS CME theDIGEST Stemmer sign.TOP PICKS CONTACT Search terms 6. Medications are a common cause of lower TEACH extremity edema – don’t forget about the gabapentinoids! 7. May-Thurner syndrome is caused by anatomical compression of the left iliac vein, and can result in unilateral edema or recurrent deep vein thrombosis. 8. Acute edema can be caused by deep vein thrombosis, cellulitis, or ruptured popliteal cyst, all of which may be difficult to differentiate from each other. 9. The physical examination should be directed at finding underlying systemic causes of lower extremity edema. 10. Management of edema usually includes compression, elevation, and avoidance of exacerbating medications. Lower Extremity Edema Notes Edema – Pathophysiology Generally speaking, venous circulation maintains a balance between hydrostatic pressure and oncotic Find pressure. Edema can result from perturbations in these forces (Trayes et al 2013). ABOUT EPISODES CRIBSIDERS DIGEST hydrostatic CME TOP PICKS CONTACT Increased pressure TEACH Search terms Venous hypertension from right-sided heart failure, venous insufficiency, constrictive pericarditis, etc. Endoluminal obstruction (e.g. venous thrombosis, popliteal cyst, etc.) Decreased oncotic pressure Low-protein states like nephrotic syndrome, hepatic failure, protein-energy malnutrition Capillary dilation Vasodilation from warmer weather Inflammatory states such as burns or cellulitis Additionally, as Cardi B teaches us, a lot of things need to be working for effective venous return. Recall that venous return is largely a passive process and requires functional valves and muscle contraction. Defects in either of these can result in diminished venous return, increased venous pressure, and resultant edema. Find ABOUT EPISODES CRIBSIDERS DIGEST CME TOP PICKS CONTACT Search terms TEACH Determining the Cause – Chronic Edema Chronic venous insufficiency Probably the most common cause (BeebeDimmer et al 2005) Prevalence increases with age More common in patients with obesity Represents a spectrum of disease from painless edema to chronic ulcerative disease A gentle reminder: bilateral cellulitis of the lower extremities is uncommon Cardiogenic causes Evaluate patients for signs and symptoms of heart failure and untreated or undiagnosed Find obstructive sleep apnea Renal causes ABOUT EPISODES CRIBSIDERS DIGEST CME TOP PICKS CONTACT Search terms Evaluate for risk factors for nephrotic TEACH syndrome Don’t forget to look for periorbital edema (and don’t forget Tony Breu’s amazing Tweetorial) Hepatic causes Evaluate for stigmata of chronic liver disease Thyroidal causes Pretibial myxedema (thyroid dermopathy) Rare manifestation of Graves’ disease Typically bilateral and non-pitting Hypothyroidism can also lead to non-pitting edema Lymphedema Can be idiopathic or secondary Secondary lymphedema can be caused by surgery or radiation Filariasis most common cause worldwide (Green 2015) Caused by an impediment of lymphatic return Chronic leakage of proteins leads to inflammation and ultimately fibrosis Find Results in thickening of the skin and tissues ABOUT DIGEST Lipedema EPISODES CRIBSIDERS CME TOP PICKS CONTACT Search terms TEACH Pathologic accumulation of adipose tissue in the lower extremities Classically spares the feet Medication-induced Thiazolidinediones. NSAIDs Calcium channel blockers Dihydropyridines more than nondihydropyridines Effect tends to be dose-dependent Edema from calcium channel blockers not effectively treated by diuretics Angiotensin-receptor blockers or ACE-inhibitors are more effective at mitigating this Gabapentinoids Mechanism thought to be due to vasodilatory effects and decreased myogenic tone (Largeau et al 2021) Oral contraceptives Corticosteroids May-Thurner syndrome Cause of unilateral lower extremity edema Find Female predominant Compression of the left iliac vein by the right iliac artery ABOUT EPISODES CRIBSIDERS DIGEST CME Search terms Can predispose toTOP leftPICKS lower CONTACT extremity DVT TEACH Neuromuscular causes Any condition that affects calf muscle strength can lead to edema (Ratchford and Evans 2017) Includes stroke, multiple sclerosis, and even lumbar radiculopathy Determining the Cause – Acute Edema Deep vein thrombosis Likelihood can be predicted by calculating Wells score Generally requires ultrasonography for diagnosis Cellulitis Clinically difficult to differentiate from DVT Ruptured popliteal cyst Classically presents with ecchymosis around the ankle Again, may be clinically challenging to differentiate from other causes Find Ultrasonography usually required to make the diagnosis ABOUT CME TOP PICKS Edema DIGEST – The Workup EPISODES CRIBSIDERS CONTACT Search terms TEACH Physical Examination Assess for symptoms of cardiac disease Assess for JVD Pitting edema can be extensive and extend proximally to the sacrum in heart failure Evaluate for pitting versus non-pitting Non-pitting edema seen in lymphedema Check for Stemmer’s sign to evaluate for lymphedema Inability to pinch the skin at the base of the toes due to skin changes Find Evaluate for superimposed cellulitis if chronic changes of venous insufficiency are seen ABOUT DIGEST CME TOP PICKS Laboratory evaluation EPISODES CRIBSIDERS CONTACT Search terms TEACH Reasonable to check urine protein-creatinine ratio In most patients, could consider comprehensive metabolic panel to evaluate albumin and electrolyte abnormalities TSH often checked to rule out thyroid causes Additional testing, such as urinalysis, complete blood count, BNP, or D-dimer, could be considered depending on patient history and risk factors Other studies Venous ultrasound studies should be ordered if there is suspicion for DVT Consider a transthoracic echocardiogram in patients with cardiopulmonary symptoms Polysomnography is appropriate for patients for whom there is high suspicion for sleep apnea Abdominopelvic imaging may be appropriate when the cause is not fully elucidated and there is suspicion for malignancy or other compressive or obstructive etiology Edema – Management Find ABOUT EPISODES CRIBSIDERS DIGEST CME TOP PICKS CONTACT Search terms TEACH General principles Stop exacerbating medications, if possible Compression stockings are generally helpful, especially for chronic venous insufficiency Avoid if arterial insufficiency is suspected Elevate the legs when possible Diuretics may not be helpful in the absence of volume overload They are not effective at mitigating edema caused by calcium channel blockers Patient education and reassurance are an important component of management There is some evidence for horse chestnut seed extract in the short-term treatment of chronic venous insufficiency (Pittler and Ernst 2012) Find Lymphedema management Best managed by a multidisciplinary team ABOUT TOP PICKS Search terms UsuallyCME includes physicalCONTACT therapy and EPISODES CRIBSIDERS DIGEST TEACH vascular surgery teams Patients typically undergo complex decongestive physiotherapy Primary care provider role is to help provide meticulous skin care and ensure care coordination Links* 1. Return of the Living Dead 2. The Medical Detectives 3. Royal Blood – Typhoons 4. Memorial Sloan Kettering Integrative Medicine website *The Curbsiders participates in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for sites to earn advertising commissions by linking to Amazon. Simply put, if you click on our Amazon.com links and buy something we earn a (very) small commission, yet you don’t pay any extra. Find
