Edema is a palpable swelling produced by excess fluid.
While lower extremities (LE) edema occurs in older patients, edema can be seen in pediatric population as well.
Recognizing the cause of edema is an important skill for psychiatrists, since many medical emergencies present initially as edema. Treatment is beyond the scope of psychiatrist's practice and is not addressed in this article.
Lower Extremities Edema
Differential of bilateral edema
Based on H&P and labs carefully consider all the potential causes of edema:
- Acute DVT (although usually unilateral) must always be considered; it is a medical emergency. Pt. needs urgent DVT/PE workup.
- Heart disease (CHF, acute MI, valvulopathies, restrictive, contrictive heart diseases) and lung disease (pulmonary hypertension)
- check cardiac enzymes, do an EKG, and echocardogram
- Renal disease producing decreased oncotic pressure, or salt/water retention (nephrotic syndrome, acute glomerulonephritis, chronic renal insufficiency).
- check UA for protein, hematuria, BMP for renal function.
- Cirrhosis, causing hypoalbuminemic edema
- Malnutrition/malabsorption: suspect in chronically ill, patients with chronic diarrhea, h/o intestinal surgery, poor feeding, eating disorders.
- Pregnancy: edema is very common. Edema of hands and face with hypertension is a medical emergency (preeclampsia)
- thyroid dysfunction (pretebial myxodema); edema is usually nonpitting.
- pelvic or intra-abdominal mass, compressing venous outflow
- benign conditions affecting women: lipedema (not same as lymphodema) and cellulite.
- MAO-Is, risperidone and other antipsychotics (rarer), lithium (most rare).
- Anti-hypertensives: beta-blockers, Ca-channel blockers, clonidine, methyldopa, reserpine, hydralazine, etc; ACE-I can cause angioedema.
- DM medications (thiazolidinediones)
- Hormones: corticosteroids, estrogen, progesterone, testosterone.
- Penicillin can cause angioedema
Differential of unilateral edema
- Deep Vein Thrombosis
- acute DVT is a medical emergency especially if accompanied by respiratory symptoms. Pt. may have h/o immobility, surgery, trauma, or smoking+oral contraceptives. Swelling is often painful; tender cord, Homan's sign on exam.
- Compartment syndrome and abscess are likewise medical emergencies
- Cellulitis is another potential medical emergency
- limb is warm, erythematous, and tender; +/- fever; order Doppler U/S to rule out DVT;
- treat with antibiotics (PO or IV); presence of an abscess is a potential medical emergency.
- Venous stasis
- benign chronic condition can be unilateral or B/L, caused by incompetent venous valves.
- there is no "acute venous stasis edema" - consider other causes.
- Dr. Manu: While calf vein thrombi are not clinically significant (due to small diameter), it takes under a week for an acute thrombus to move from calf veins into popliteal or femoral veins. In larger veins, the thrombi will partially obstruct the lumen and will grow with significant risk of causing a PE. Therefore, with clinical suspicion (asymmetric LE edema), and common situation when calf veins were not visualized on the LE Doppler, and larger veins are DVT free, doctor should repeat the Doppler of LE in 4-6 days.
- While on-call, if evaluating acute unilateral leg edema on inpatient unit, always send the patient to the ED, since so many common causes are medical emergencies (see above).
- a tumor in the thorax or mediastinum can compress superior vena cava, producing SVC syndrome, characterized by venous congestion of face and, to a lesser degree, neck and arms. Headache can indicate increased ICP. SVC syndrome is another medical emergency.
- Lymphedema is a chronic painless swelling that may follow lymph node resection, most commonly affecting one arm after breast CA surgery; may also be congenital, usually chronic and painless.
- Reflex sympathetic dystrophy is a rare cause of gradual painful U/L edema.
- Factitious edema may be produced by applying tourniquet around a limb by a psychiatric patient.
Similar general approach is taken to determining the cause of edema: consider and evaluate for kidney, heart, and liver disease. Also important to remember are pregnancy, anemia, allergic reactions and vasculitis (Kawasaki disease and SLE) as potential causes.
Manu et. al. Handbook of Medicine in Psychiatry 2006