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Transcript of Happy Year
Awatif Jamal, MD, MSc, FRCPC, FIAC Consultant & Associate Professor Department of PathologyKing Abdulaziz University Hospital
Hemodynamic Disorders Thrombosis & Shock Edema Hyperemia and Congestion Hemorrhage Hemostasis & Thrombosis Embolism Infarction Shock Edema
INTRODUCTIONThe health of cells and tissues depend on; 1-Intact circulation ; to deliver oxygen and remove wastes. 2-Normal fluid homeostasis; which encompasses the following;A- maintenance of BV wall integrity .B- maintenance of intravascular pressure.C- maintenance of protein content or osmolarity within BV.D- maintenance of blood as a liquid until such time as injury necessitates clot formation.
EDEMAFluid extravasations and accumulation in the interstitial spaces60% of body weight is water, distributed as follow: Two thirds intracellular 5% intravascular The rest is interstitial
EDEMAIncreased fluid in the interstitial tissue spacesFluid may also accumulate in body cavities:HydrothoraxHydropericardiumHydroperitoneum is also called Ascites
Massive generalized edema is called Anasarca
PathogenesisThe opposing effects of vascular hydrostatic pressure and plasma colloid osmotic pressure are the major factors that control the movement of fluid between vascular and interstitial tissues.
Normally, the exit of fluid into the interstitium from the arteriolar end of microcirculation is nearly balanced by inflow of fluid at the venular end; a small residual amount of excess interstitial fluid is drained by the lymphatics
Fluid HomeostasisHomeostasis is maintained by the opposing effects of:Vascular Hydrostatic Pressure and Plasma Colloid Osmotic Pressure
Edema Fluid = TRANSUDATEtransudate is protein-poor (specific gravity 1.020) = (inflammatory edema)
Pathophysiologic Categories of Edema II. Reduced Plasma Oncotic PressureIII. InflammationIV. OthersI. Increased Hydrostatic Pressure
Patho-physiologic Categories of EdemaIncreased Hydrostatic PressureIncreased intravascular pressure may be due to 1- Impaired venous return;Localized: Venous Thrombosis in lower extremities (local edema). Generalized: Congestive Heart Failure (generalized edema).
2- Increased arteriolar dilatation;HeatNeurohumoral dysregulation
Increased Hydrostatic Pressure
Congestive Heart Failure: Congestive Heart Failure is the most common cause of EDEMA due to Increased Hydrostatic PressureGeneralized increased venous pressure, resulting in systemic edema, occur most commonly in CONGESTIVE HEART FAILURE
Increased Hydrostatic Pressure Congestive Heart FailureMechanism:The Pump is FAILING!!! Cardiac outputBlood backs up, first into the lungs then into the venous circulation increasing Central Venous Pressure (CVP) increased capillary pressure (Hydrostatic Pressure)Leading to Generalized Edema
Congestive Heart Failure & Decreased Renal PerfusionCongestive heart failure Decreased Cardiac Output Decreased ARTERIAL blood volume Less arterial bloodLess renal perfusion...The Kidney doesnt see enough blood coming through .
Congestive Heart Failure& Decreased Renal PerfusionDecreased Renal Perfusion activates the Renal Defense Mechanisms:Renin-Angiotensin-Aldosterone axis Na & H2O retentionRenal VasoconstrictionIncreased Renal Anti-diuretic Hormone (ADH)
Congestive Heart Failure& Decreased Renal PerfusionThe net result will be increased intravascular volume to increase the COP.
The failing heart cant increase the COP so the extra fluid load will lead to additional increase in the venous pressure and More EDEMA .
Congestive Heart Failure
Pathophysiologic Categories ofEdemaI. Increased Hydrostatic Pressure
III. Inflammation IV. OthersII. Reduced Plasma Oncotic Pressure
II. Reduced Plasma Oncotic PressureAlbumin:the serum protein MOST responsible for the maintenance of colloid osmotic pressure.A decrease in osmotic pressure can result from: Protein Loss or Protein Synthesis
II. Reduced Plasma Oncotic PressureIncreased albumin Loss: Nephrotic SyndromeIncreased permeability of the glomerular basement membrane loss of protein Reduced albumin synthesis: CirrhosisProtein malnutritionEFFECT: is movement of fluid into the interstitial tissue with resultant plasma volume contraction.
Pathophysiologic Categories ofEdema IV. OthersI. Increased Hydrostatic Pressure
II. Reduced Plasma Oncotic PressureIII. Inflammation Localized EdemaIncreased Vascular Permeability
Pathophysiologic Categories ofEdemaI. Increased Hydrostatic Pressure
II. Reduced Plasma Oncotic PressureIII. Inflammation IV. Others Lymphatic Obstruction Water and Sodium Retention
Impaired lymphatic drainage with resultant lymphedema LOCALIZED EDEMA caused by : INFLAMMATION or NEOPLASTIC OBSTRUCTION
Inflammatory Lymphatic ObstructionFilariasis A parasitic infection which leads to lymphatic and lymph node fibrosis in the inguinal region resulting in edema of the external genitalia and lower extremity called ELEPHANTIASIS
Neoplastic Lymphatic ObstructionIn cases of CA breast the resection and/or radiation of axillary lymphatic channels and lymph nodes can lead to -- arm edemaCarcinoma of breast with obstruction of superficial lymphatics can lead to edema of the skin with an unusual appearance of the breast skin - peau dorange (orange peel)
EDEMA - SummaryHEARTLIVERKIDNEYINCREASEDHYDROSTATICPRESSURECongestive Heart FailureAscitesVenous ObstructionDECREASED ONCOTICPRESSURENephrotic SyndromeCirrhosisProtein MalnutritionINCREASEDPERMEABILITYInflammationLYMPHATICOBSTRUCTIONInflammatoryNeoplastic
Subcutaneous EdemaEdema of the subcutaneous tissue is most easily detected Grossly (not microscopically)Push your finger into it and a depression remains
Annoying but Points to Underlying DiseaseIt can impair wound healing or clearance of Infection
Dependent Edema is a prominent feature of Congestive Heart Failure; in legs if standing or sacrum in sleeping patient
Periorbital edema is often the initial manifestation of Nephrotic Syndrome, while late cases will lead to generalized edema.Edema
Pulmonary Edemais most frequently seen in Congestive Heart FailureMay also be present in renal failure, adult respiratory distress syndrome (ARDS), pulmonary infections and hypersensitivity reactions
Pulmonary EdemaThe Lungs are typically 2-3 times normal weightCross sectioning causes an outpouring of frothy, sometimes blood-tinged fluidIt may interfere with pulmonary function
Pulmonary EdemaClinical Correlation May cause death by interfering with Oxygen and Carbon Dioxide exchangeCreates a favorable environment for infectionTHINK it resembles Culture Media!!!
Brain EdemaTrauma, Abscess, Neoplasm, Infection (Encephalitis due to say West Nile Virus), etc
Brain EdemaClinical Correlation The big problem is: There is no place for the fluid to go!Herniation into the foramen magnum will kill
Clinical Correlation of Edema
The effect of edema may be just annoying to fatal condition. It usually points to an underlying disease.However, it can impair wound healing or clearance of Infection.Creates a favorable environment for infection.THINK Culture MediaMay cause death by interfering with Oxygen and Carbon Dioxide exchange.
The surface of the brain with cerebral edema demonstrates widened gyri with a flattened surface. The sulci are narrowed
Acute cerebral swelling can also often produce herniation of the cerebelllar tonsils into the foramen magnum. Note the cone shape of the tonsils around the medulla in this cerebellum.