Additional Factors in Diagnosis The color, thickness, and sensitivity of the skin are significant. Local tenderness and warmth suggest inflammation. Local cyanosis may signify venous obstruction. In individuals who have had repeated episodes of prolonged edema, the skin over the involved areas may be thickened, indurated, and often red. Estimation of the venous pressure is of importance in evaluating edema. Ordinarily, a significant generalized increase in venous pressure can be recognized by the level at which cervical veins collapse (Chap. 220). In patients with obstruction of the superior vena cava, edema is confined to the face, neck, and upper extremities, in. | Chapter 036. Edema Part 7 Additional Factors in Diagnosis The color thickness and sensitivity of the skin are significant. Local tenderness and warmth suggest inflammation. Local cyanosis may signify venous obstruction. In individuals who have had repeated episodes of prolonged edema the skin over the involved areas may be thickened indurated and often red. Estimation of the venous pressure is of importance in evaluating edema. Ordinarily a significant generalized increase in venous pressure can be recognized by the level at which cervical veins collapse Chap. 220 . In patients with obstruction of the superior vena cava edema is confined to the face neck and upper extremities in which the venous pressure is elevated compared with that in the lower extremities. Severe heart failure may cause ascites that may be distinguished from the ascites caused by hepatic cirrhosis by the jugular venous pressure which is usually elevated in heart failure and normal in cirrhosis. Determination of the concentration of serum albumin aids importantly in identifying those patients in whom edema is due at least in part to diminished intravascular colloid oncotic pressure. The presence of proteinuria also affords useful clues. The absence of proteinuria excludes nephrotic syndrome but cannot exclude nonproteinuric causes of renal failure. Slight to moderate proteinuria is the rule in patients with heart failure. Approach to the Patient Edema An important first question is whether the edema is localized or generalized. If it is localized those local phenomena that may be responsible should be considered. If the edema is generalized it should be determined first if there is serious hypoalbuminemia . serum albumin 25 g L. If so the history physical examination urinalysis and other laboratory data will help evaluate the question of cirrhosis severe malnutrition or the nephrotic syndrome as the underlying disorder. If hypoalbuminemia is not present it should be determined if there is .
