Edema

Introduction

Edema is a palpable swelling produced by excess fluid. While lower extremities (LE) edema occurs in older patients, all edema can be seen in pediatric population as well. LE edema will be discussed here as well.

Lower Extremities Edema

Bilateral edema differential

Based on H&P and labs carefully consider all the potential causes of edema:

• Acute DVT must be considered (usually unilateral), 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.

Drug-induced edema

• MAO-Is, risperidone and other antipsychotics, lithium.
• Anti-hypertensives: beta-blockers, Ca-channel blockers, clonidine, methyldopa, reserpine, hydralazine, etc; ACE-I can cause angioedema.
• DM medications (thiazolidinediones)
• NSAIDs
• 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
  • limb is hot and tender; +/- fever; order Doppler U/S to rule out DVT;
  • teat 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.
• Other
  • Lymphedema is a chronic painless swelling that may follow lymph node resection, most commonly affecting one arm after breast CA surgery.
  • Reflex sympathetic dystrophy is a rare cause of gradual painful U/L edema.
  • Factitious edema may be produced by applying tourniquet around a limb

Other pearls

• 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.

References

Manu et. al. Handbook of Medicine in Psychiatry 2006