Summary
Peripheral edema is the presence of excess interstitial fluid in the tissue of the extremities, which causes palpable swelling.[1]
Edema develops when microvascular filtration, and therefore interstitial fluid production, exceeds lymph drainage for a sustained period. This could be because the microvascular filtration rate is high, lymph flow is low, or both.[2]
[Figure caption and citation for the preceding image starts]: Development of edema: an imbalance between the filtration of fluid from the bloodstream and drainage via the lymph system.Created by BMJ Knowledge Centre [Citation ends].
The body has a number of homeostatic mechanisms that serve to maintain interstitial fluid balance, and these must be overwhelmed before fluid buildup becomes evident as peripheral edema. Clues generated by the history, physical examination, and targeted evaluation help to identify the factors affecting lymphatic drainage and microvascular filtration. In many patients, multiple factors contribute to the development of peripheral edema.
Peripheral edema is called lymphedema when it is predominantly caused by inadequate lymphatic drainage.
Differentials
Common
- Heart failure with reduced ejection fraction (HFrEF)
- Heart failure with preserved ejection fraction (HFpEF)
- Cor pulmonale
- Deep vein thrombosis
- Chronic venous insufficiency
- Nephrotic syndrome
- Cirrhosis
- Pregnancy
- Premenstrual edema
Uncommon
- Pericardial effusion
- Constrictive pericarditis
- Restrictive cardiomyopathy
- Tricuspid regurgitation
- Sleep apnea
- Nonthrombotic venous outflow obstruction/May-Thurner syndrome
- Hepatic venous outflow obstruction (includes Budd-Chiari syndrome, portal vein thrombosis, and hepatic veno-occlusive disease)
- Renal failure
- Protein-losing enteropathy
- Angioedema
- Sepsis
- Compartment syndrome
- Primary lymphedema
- Secondary lymphedema
- Idiopathic
- Severe malnutrition
- Hypothyroidism/myxedema
- Medication-induced edema
- Ruptured Baker cyst
- Pelvic tumor causing external pressure on pelvic veins
Contributors
Authors
Laura D. Rosenthal, DNP, ACNP, FAANP
Associate Professor, College of Nursing
University of Colorado Anschutz Medical Campus
Denver
CO
Disclosures
LDR declares that she has no competing interests.
Ethan Cumbler, MD
Professor of Medicine
Division of Hospital Medicine
Department of Internal Medicine
University of Colorado
Denver
CO
Disclosures
EC declares that he has no competing interests.
Peer reviewers
S. Wamique Yusuf, MD
Associate Professor
Department of Cardiology
University of Texas MD Anderson Cancer Center
Houston
TX
Disclosures
SWY declares that he has no competing interests.
Piyush Raj, MD
Basic Physician Trainee RACP
Logan Hospital
Meadowbrook
Queensland
Australia
Disclosures
PR declares that he has no competing interests.
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