superficial introduction to the topic for bachelor level

1. OEDEMA
Dr. Saugat Chapagain

2. OEDEMA/ EDEMA
 Abnormal and excessive accumulation of free fluid in interstitial
spaces and serous cavities.
 Site:
• In body cavities-
• Ascites, hydrothorax, pleural effusion, pericardial effusion, etc.
• In interstitial space-
• Lies free in the interstitial space.
• Can be displaced with pressure (Pitting)
• Can not be displaced (non pitting) e.g. myxoedema

3. ALL OEDEMA ARE PITTING
EXCEPT ONES DUE TO
LYMPHATIC OBSTRUCTION
AND MYXOEDEMA

4. TYPES
 Based on site/ distribution:
• Localized
• Pulmonary effusion, ascites, hydrothorax, pericardial effusion, lymph
edema, peripheral venous obstruction.
• Generalized (usu. Transudative) (anasarca/ dropsy)
• Renal, cardiac, hepatic, famine(nutritional
 Based on fluid composition:
• Transudate-
• Non inflammatory, usu. Systemic.
• Exudate-
• Inflammatory

5. PATHOGENESIS
 Increased hydrostatic pressure
• Force that drives fluid from capillary into the interstitial space.
• Counteracts plasma oncotic pressure (force that resorbs interstitial fluid)
1. Increased venous return
• CCF, Constrictive pericarditis.
• Venous obstruction, thrombosis, postural
2. Arteriolar dilation
• Heat, neuro-humoral dysregulation
 Reduced plasma oncotic pressure
• Hypoproteinemia, nephritic synd. GN, liver cirrhosis, PEM

6. PATHOGENESIS (CNTD…)
 Lymphatic obstruction
• Inflammatory (filariasis)
• Neoplastic
• Post surgical
• Post radiation
 Tissue factors
• If sc tissues are loose e.g. eyelids in old age
 Sodium and water retention
• Excess salt intake with renal insufficiency
• Increased reabsorption of sodium
 In inflammation