EDEMA Basic Course of Diagnosis
Definition A clinical apparent increase in the interstitial fluid volume. Distribution: local general Special form: ascites hydrothorax
Pathogenesis Total body water(tbw): 2/3 body weight intracellular 2/3 TBW Interstitial 3/4 extracellular 1/3 starling force intravascular 1/4 Starling force depends on : hydrostatic pressure colloid oncotic pressure
Pathogenesis Disturbed starling forces(reduced effective circulating volume,edema formation) systemic venous pressure increase right-sided heart failure,constrictive pericarditis local venous pressure increase left-sided heart failure,vena cava obstruction, portal vein obstruction reduced oncotic pressure nephrotic syndrome,decreased albumin synthesis combined disorders cirrhosis
Primary hormone excess (increased effective circulating volume) primary aldosteronism Cushing s syndrome SIADH Primary renal sodium retention (increased effective circulating volume) renal failure SIADH: syndrome of inappropriate antidiuretic hormone production
Capillary damage inflammation due to the bacteria infection,allergic reaction,immune reaction Lymphatic obstruction
Clinical causes of edema General edema: Congestive Heart Failure Nephrotic Syndrome and Other Hypoalbuminemic States Cirrhosis Drug-Induced Idiopathic Edema
Localized edema: Obstruction of venous (and lymphatic) drainage of a limb
Table 37-2. Principal Causes of Generalized Edema: History, Physical Examination, and Laboratory Findings Organ System Cardiac Hepatic Renal History Physical Examination Laboratory Dyspnea with exertion prominent-often associated with orthopnea-or paroxysmal nocturnal dyspnea Dyspnea infrequent, except if associated with significant degree of ascites; most often a history of ethanol abuse chronic: decreased appetite, metallic or fishy taste, altered sleep pattern, difficulty concentrating, restless legs or myoclonus: dyspnea can be present, but generally less prominent than in heart failure Elevated jugular venous pressure, ventricular (S3) gallop; occasionally with displaced or dyskinetic apical pulse; peripheral cyanosis, cool extremities, small pulse pressure when severe Frequently associated with ascites; jugular venous pressure normal or low; BP lower than in renal or cardiac disease; jaundice, palmar erythema, Dupuytren's contracture, spider angiomata, male gynecomastia; asterixis and other signs of encephalopathy BP may be elevated; hypertensive or diabetic retinopathy in selected cases; nitrogenous fetor; periorbital edema may predominate; pericardial friction rub in advanced cases with uremia NOTE: S3, third heart sound.source: From GM Chertow, GE Thibault, Approach to the patient with edema, in L Goldman, E Braunwald (eds): Primary Cardiology. Philadelphia, Saunders, 1998. Findings Elevated BUN/Cr ratio common; elevated uric acid; serum Na diminished; liver enzymes occasionally elevated with hepatic reductions congestion in Alb, Cho, transferrin, fibrinogen liver enzymes elevated, tendency toward hypokalemia, respiratory alkalosis; macrocytosis from folate deficiency hypoalbuminemia; elevation of serum creatinine and urea hyperkalemia, metabolic acidosis, hyperphosphatemia, hypocalcemia, anemia (usually normocytic)
Malnutrition: weight loss occurs from lower extremities diet grossly deficient in protein over a long period Protein-losing enteropathy Severe burn Idiopathic edema: exclusive in,periodic episodes of edema(unrelated to MC)
Miscellaneous:located pretibial region,periorbital region hypothyroidism(myxedema) Drug-induced edema Exogenous hyperadrecocortism Estrogen vasodilators
Localized edema: Local inflammation Thrombosis Thrombophlebitis filariasis
Accompanied symtoms With hepatomegaly With gross proteinuria With dyspnea Related with menstrual cycle
Approach to the Patient Localized or generalized? Hydrothorax or ascites? Sites accompanied symptom