Chapter 036. Edema (Part 7) pptx

Edema Part 7 Additional Factors in Diagnosis The color, thickness, and sensitivity of the skin are significant.. In individuals who have had repeated episodes of prolonged edema, the s

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, e.g., 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 evidence of congestive heart failure of a severity to promote generalized edema Finally, it should be determined whether the patient has an adequate urine

output, or if there is significant oliguria or anuria These abnormalities are discussed in Chaps 45, 273, and 274

Further Readings

Abassi ZA et al: Control of extracellular fluid volume and the

pathophysiology of edema formation, in The Kidney, 7th ed, BM Brenner (ed)

Philadelphia, Saunders, 2004, pp 777–856

Chertow GM: Approach to the patient with edema, in Cardiology for the

Primary Care Physician, 2d ed, E Braunwald, L Goldman (eds) Philadelphia,

Saunders, 2003, pp 117–128

Diskin CJ et al: Edema, oncotic pressure, and free entropy: Novel

considerations for treatment of edema through attention to thermodynamics Nephron 78:131, 1998 [PMID: 9496727]

McCullough JC: Renal disorders and heart disease, in Braunwald's Heart

Disease, 7th ed, D Zipes et al (eds) Philadelphia, Saunders, 2005

O'Brien JG et al: Treatment of edema Am Fam Physician 71:2111, 2005 [PMID: 15952439]

Streeten DH: Idiopathic edema Pathogenesis, clinical features, and treatment Endocrinol Metab Clin North Am 24:531, 1995 [PMID: 8575408]