Its occurrence in patients with heart failure signals the onset of right ventricular failure. Elevated jugular venous pressure should be sought on physical examination. Other cardiac causes of peripheral edema, in the absence of left ventricular failure, include constrictive pericarditis and primary right ventricular failure secondary to pulmonary arterial hypertension. Noncardiovascular diseases that cause peripheral edema include chronic renal failure, profound hypoalbuminemia, and Cushing's disease. Cyanosis is said to be peripheral when it is seen only in the extremities.
Peripheral cyanosis is the result of decreased blood flow to the skin secondary to vasoconstriction.
Common causes of peripheral cyanosis include shock and exposure to cold. Peripheral cyanosis is transient and not associated with clubbing of the fingernails. Fingers and toes are often clubbed. Clubbing may also be familial and may not be associated with decreased arterial oxygen saturation. Patients often know when clubbing runs in the family.