Cause	Example
Increased intravascular hydrostatic pressure	Heart failure, lung disease, occlusive thrombi
Decreased intravascular (plasma) oncotic pressure	hypoalbuminemia due to liver failure, starvation, protein loss from the kidney, intestine enteropathies and parasites), burns
Decreased lymphatic drainage	Lymph vessel compression or obstruction due to neoplasia, inflammation, or fibrosis (rarely congenital)
Increased microvascular permeability	Inflammation/immunologic stimuli with local release of inflammatory mediators

Puppies with anasarca (diffuse congenital edema)

Pulmonary Edema (gross and histology)

Congenital Lymphedema

Edema in a dog with mammary tumor