Hemodynamic Disorders Thrombosis Shock Edema l Hyperemia and

Hemodynamic Disorders, Thrombosis & Shock • Edema l Hyperemia and Congestion l Hemorrhage l Hemostasis & Thrombosis l Embolism l Infarction l Shock l

EDEMA Fluid extravasations and accumulation in the interstitial spaces

EDEMA Increased fluid in the interstitial tissue spaces l l Fluid may also accumulate in body cavities: 1. Hydrothorax 2. Hydropericardium 3. Hydroperitoneum is also called Ascites Massive generalized edema is called Anasarca

Fluid Homeostasis is maintained by the opposing effects of: 1. Vascular Hydrostatic Pressure and 2. Plasma Colloid Osmotic Pressure Lymphatics

Edema Fluid = TRANSUDATE l l A transudate is protein-poor (specific gravity <1. 012) An exudate is protein-rich (specific gravity >1. 020) = (inflammatory edema)

Pathophysiologic Categories of Edema I. Increased Hydrostatic Pressure II. Reduced Plasma Oncotic Pressure III. Inflammation IV. Others

Pathophysiologic Categories of Edema Increased Hydrostatic Pressure 1. Due to impaired venous return A) Localized: § B) Venous Thrombosis Generalized: § Congestive Heart Failure 2. Due o increased arteriolar dilatation

Increased Hydrostatic Pressure Congestive Heart Failure: “Generalized increase in venous pressure, with resultant SYSTEMIC EDEMA occurs MOST COMMONLY in CONGESTIVE HEART FAILURE” {*** Thus, Congestive Heart Failure is the most common cause of EDEMA due to Increased Hydrostatic Pressure}

Congestive Heart Failure Overall, there are TWO main effects. . . 1. Increased Central Venous Pressure 2. Decreased Renal Perfusion

Increased Hydrostatic Pressure: Congestive Heart Failure Mechanism: l The Pump is FAILING!!! Cardiac output l Blood backs up, first into the lungs then into the venous circulation increasing Central Venous Pressure (CVP) increased capillary pressure (Hydrostatic Pressure) l Leading to Edema

Congestive Heart Failure: & Decreased Renal Perfusion l Congestive heart failure Decreased Cardiac Output Decreased ARTERIAL blood volume “Less arterial blood…Less renal perfusion. . . The Kidney doesn’t see enough blood coming through …….

Congestive Heart Failure: & Decreased Renal Perfusion activates the Renal Defense Mechanisms: 1. Renin-Angiotensin-Aldosterone axis Na & H 2 O retention 2. Renal Vasoconstriction 3. Increased Renal Anti-diuretic Hormone (ADH)

Congestive Heart Failure - Summary Central Venous Pressure Renal Perfusion ADH Renin Renal Vasoconstriction

Pathophysiologic Categories of Edema I. Increased Hydrostatic Pressure II. Reduced. Plasma Oncotic Pressure II. Reduced Oncotic Pressure III. Inflammation IV. Other

Reduced Plasma Osmotic Pressure l “…Albumin: is the serum protein MOST responsible for the maintenance of colloid osmotic pressure. ” l A decrease in osmotic pressure can result from: 1. Protein Loss or 2. Protein Synthesis

Reduced Plasma Osmotic Pressure Increased albumin loss: 1. l Nephrotic Syndrome l Increased permeability of the glomerular capillary wall loss of protein Reduced albumin synthesis 2. l Cirrhosis l Protein malnutrition

Pathophysiologic Categories of Edema I. Increased Hydrostatic Pressure II. Reduced Plasma Oncotic Pressure III. Inflammation IV. Other

Pathophysiologic Categories of Edema I. Increased Hydrostatic Pressure II. Reduced Plasma Oncotic Pressure III. Inflammation IV. Others: - Lymphatic Obstruction - Sodium & water retention

Lymphatic Obstruction l Impaired lymphatic drainage with resultant lymphedema l usually localized l usually due to: l INFLAMMATION or l NEOPLASTIC OBSTRUCTION

Lymphatic Obstruction l Filariasis – l A parasitic infection affecting inguinal lymphatics resulting in elephantiasis

Lymphatic Obstruction Neoplastic l Resection and/or radiation to axillary lymphatics in breast cancer patients can lead to -- arm edema l Carcinoma of breast with obstruction of superficial lymphatics can lead to edema of breast skin -- --with an unusual appearance: “peau d’orange” (orange peel)

EDEMA INCREASED HYDROSTATIC PRESSURE Congestive Heart Failure Ascites Venous Obstruction INCREASED PERMEABILITY Inflammation Summary l l l HEART LIVER KIDNEY DECREASED ONCOTIC PRESSURE Nephrotic Syndrome Cirrhosis Protein Malnutrition LYMPHATIC OBSTRUCTION Inflammatory Neoplastic

GENERALIZED EDEMA l l l HEART LIVER KIDNEY

Edema Morphology Subcutaneous Edema l l Edema of the subcutaneous tissue is most easily detected Grossly (not microscopically) l Push your finger into it l and a depression remains Dependent Edema is a prominent feature of Congestive Heart Failure l Facial Edema is often the initial manifestation of Nephrotic Syndrome

Edema Clinical Correlation: Subcutaneous Edema l Annoying but Points to Underlying Disease l However, it can impair wound healing or clearance of Infection

Edema Morphology Pulmonary Edema is most frequently seen in Congestive Heart Failure l May also be present in renal failure, adult respiratory distress syndrome (ARDS), pulmonary infections and hypersensitivity reactions

Pulmonary Edema Gross: l The Lungs are typically 2 -3 times the normal weight l Cross sectioning causes an outpouring of frothy, sometimes blood-tinged fluid

Normal Pulmonary Edema

Edema Clinical Correlation: Pulmonary Edema l May cause death by interfering with Oxygen and Carbon Dioxide exchange l Creates a favorable environment for infection l THINK it resembles “Culture Media”!!!

Edema of the Brain l Trauma, Abscess, Neoplasm, Infection (Encephalitis due to say… West Nile Virus), etc

Clinical Correlation: Edema of the Brain l The big problem is: There is no place for the fluid to go! l Herniation into the foramen magnum will kill