Edema-水腫英語課件

1、EdemaZhou YunThe Affiliated Hospital of Medical College of Ningbo UniversityEmergency DepartmentObjective Definition Classification Etiology and pathogenesis Differential diagnosisDefinition The excessive accumulation of intestitial fluid A pathologic process caused by diseases Not accompanied with

2、cellular edemaClassification According to the range that edema fluid spreads to: Generalized edema Localized edema According to the cause of edema: Renal edema Hepatic edema Cardiac edema Malnutritional edema lymphedemaClassification Generalized edema: Puffiness of the face Indentation of the skin “

3、pitting edema” Ascites & Hydrothorax Localized edemeEdemaPitting edemaAscitesEtiology and pathogenesis Imbalance of fluid exchange between plasma and interstitial compartment Imbalance of fluid exchange between extra- and intra-bodyImbalance of fluid exchange between plasma and interstitial comp

4、artmentCapillariesFigure 7-7Total Pressure Differences Inside and Outside Capillarypermeabilityobstruction1. Increased capillary blood pressure Causes:Elevated plasma volume Increased venous pressure General venous pressure, i.e. congestive heart failureLocal venous pressure, i.e. venous thrombosisA

5、rteriolar dilation i.e. acute imflammationCapillary blood pressureForce driving fluid into interstitiumFormation of interstitial fluidEdemaWhen greater than lymphatic compensatory return2. Decreased plasma colloid osmotic pressureCauses: Plasma albumin content decrease Decrease of protein production

6、 i.e. hepatic cirrhosis, malnutrition Excessive loss of protein i.e. nephrosis Elevated catabolism of protein i.e. chronic debilitating diseases, such as malignant tumor Plasma colloid osmotic pressureForce drawing water back into capillary from interstitiumFormation of interstitial fluidEdemaWhen g

7、reater than lymphatic compensatory return3. Obstruction of lymphticCauses:Blockage by cancerBlockage by infection, especially with filarial4. Increased capillary permeabilityCapillary permeabilityFiltration of more protein from capillary to interstitiumformation of interstitial fluidEdemaWhen greate

8、r than lymphatic compensatory returnPlasma colloid osmotic pressureCauses: InflammationInfectionBurnAllergic responseTraumaAnoxiaAcidosisImbalance of fluid exchange between extra- and intra-body- Renal retention of sodium and waterIn normal condition, 99-99.5% of total volume of sodium and water fil

9、trated via glomeruli are reabsorbed by tubules.60-70% of filtrates are actively reabsorbed by proximal convoluted tubule.The reabsorptions of sodium and water at distal tubule and collection duct are regulated by hormone.Glomerular( filtration) and tubular (reabsorption) balance(G-T balance)Retentio

10、n of sodium and waterGFR (glomerular filtration rate) decreases, while tubular reabsorption does not decrease accordingly; Tubular reabsorption increases, while GRF does not increased.GFRReabsorption of proximal tubuleReabsorption of distal tubule and collection tubuleG-T imbalanceFactors determinin

11、g the GFR: Filtration area and membrane permeability Filtration pressure Effective circulating blood volume or renal blood volume1. Decreased glomerular filtration rate (GFR)1.GFRCauses Extensive glomerular damage Acute or chronic glomerulonephritis Decrease of effective circulating blood volume Con

12、gestive heart failure, nephrotic syndromeRenal blood volumeRenin- angiotensin systemSympathetic - adrenal medullary system GFR- Increased reabsorption in proximal tubuleIncreased filtration fraction (FF)2.glomerular filtration rate (GFR)renal plasma flow (RPF)=FFGFR: amount of plasma filtered at glo

13、merulus into Bowmans capsuleFF is the fraction of renal plasma flow that is filtered at the glomerulusIn normal condition: FF: 20%The protein concentration in the plasma entering the peritubular capillaries increasesThe peritubular capillary oncotic pressure increasesEnhancing fluid reabsorption fro

14、m the renal interstitial space to the capillaryDecreases renal interstitial pressurefavoring reabsorption across the tubular epithelium and minimizing back flux from the renal interstitial space to the tubule lumen.Reabsorption in proximal tubuleIncreased FF Increased FF make elevated reabsorption o

15、f proximal tubuleCauses of FF increasingCongestive heart failure Nephrotic syndromeDecreased effective circulatory blood volumeSympathetic-adrenal medullary system excitingEfferent arteriole constricts stronger than afferent oneEfferent arteriole resistanceGFR is increased relative to renal plasma f

16、lowFFCongestive heart failureNephrotic syndromeEffective circulatory blood volumeADH secretionRenal blood flowRenal perfusion pressureGFRsodium at macula densaSecretion of renin by Juxtaglomerular cell Sympathetic nerve excitationRenin-angiotensin-aldosterone system activation Retention of sodium an

17、d waterStimulation of volume-receptor in left atrium and thoracic vessel-Increased reabsorption in distal tubule and collecting ductIncreased ADH (antidiuretic hormone) and ADS (aldosterone) secretion3. Question Why does congestive heart failure cause edema? General venous pressure Plasma colloid os

18、motic pressur because of dilution of blood Dysfunction of lymphatic return because of increased venous pressure GFR FF ADH and ADSDifferential diagnosis Heart failure Renal diseases Cirrhosis Nutritional origin Idiopathic OthersDifferential diagnosisHeart Failure Occurs at lower part of the body (lo

19、wer extremities) Symmetric location The presence of heart diseases Cardiac enlargement Gallop rhythm Dyspnea Basilar rales Venous distention HepatomegalyDifferential diagnosisRenal diseases Hypoalbuminemia & Retention of sodium and water Associated :HematuriaProteinuriaHypertention Impaired renal functional test Characteristic of edema Puffiness of the face Differential diagnosisCardiac/Renal disease Renal CardiacLocation onset from the face, onset from the lower periobital areas part of the bodyProgression progress quickly progress slowlyIden