LECTURE: WEEK: CARDIOVASCULAR DISORDERS 1 FUNCTION BLOOD CIRCULATION To and From all cells in the body it: Distribute nutrients. Movement of blood From the heart, through the body, back to the heart systemic Remove waste Failure to do this would result in: The larger high-pressure system Restricted perfusion Pulmonary deficient nutrient supply and waste removal Movement of blood From the heart to the lungs For oxygenation, then back to the heart Cell death in thereforl loss of Function in all organ systems COMPOSITION OF BLOOD BLOOD VESSELS Capillaries Arteries Veins plasma (55%) Continuous - Tightly bound Found in skin and muscle with small gaps Away From the Blood towards heart the heart High pressure Low pressure Thick wall Thin walls Fenestrated - Large pores that Facilitate exchange and Found in kidneys or small intestine buffy coat red blood cells ( 25% ) STRUCTURE AND FUNCTION OF CHAMBERS The right side of the heart pumps blood to the lungs (right atrium) and (right ventricle) HAEMODYNAMICS The left side of the heart pumps blood out of the aorta, to the rest of the body (left atrium) and (left ventricle VASCULAR RESISTANCE As blood Flows through blood vessels and creates a resistance - the opposition to bloodFlow due to the Friction between blood and the walls of the blood vessels. This depends on: STRUCTURE AND FUNCTION OF VALUES Valves open and close in response to pressure changes and prevent backFlow of blood. Atrioventricular - tricuspid (right), bicuspid/ mitral (left). Semilunar - pulmonary (right), aortic (left) 1. Viscosity of blood 2. Length (total) of blood vessel 4. Radius of blood vessel lumen LAYERS OF THE HEART WALL LAMINAR FLOW Epicardium (visceral layer) - protection Occurs is under normal conditions, and is characterised by the smooth Flow of Fluid (blood) in layers that do not mix with each other. Fluid is at the centre and Flows Faster where the blood touches the walls of the vessel Myocardium - cardiac muscle tissue Endocardium - endothelial cells Heart: The Great Vessels Fluid moves in lanes due to the viscosity differences (axial stream) BULK FLOW Important For the regulation of relative volumes of blood and interstitial Fluid A passive process that Flows From high-pressure to low-pressure areas Controlled by the osmotic pressure Superior vena cava Right pulmonary artery Pulmonary trunk Right pulmonary veins Inferior vena cava Aorta Left pulmonary artery Left pulmonary veins
LECTURE: HEMODYNAMIC DISORDERS WEEK: 1 OEDEMA . swelling which results From the movement of Fluid From blood vessels into the interstitial Fluid. Protein poor (transudate) or protein rich ( exudate) · oedema may be caused by: - Increased hydrostatic pressure (heart Failure) - Increase vascular permeability (inflammation) Hydrostatic pressure A. NORMAL B. EXUDATE C. TRANSUDATE Increased hydrostatic pressure = Colloid osmotic pressure Plasma proteins No net fluid or protein leakage Increased interendothelial spaces Inflammation Vasodilation and stasis Fluid and protein leakage Decreased colloid osmotic pressure Fluid leakage CLINICAL MANIFESTATIONS Signs and symptoms are dependent on location: Peripheral (legs/arms) swelling or puffiness in the tissue directly