The Cardiovascular System: The Circulatory System

The heart forces the ‘oxygenated’ blood through a range of connecting blood vessels specifically speaking arteries which travel around your body providing your cells with the necessary materials that the blood contains. As the blood reaches your cells the oxygen is released in order for the cells to function. The cells then give out waste materials which can include co2 and water. In order for your blood to receive these waste products they absorb it. We now have deoxygenated blood which goes through your veins aiming towards your heart.

Ventilation/perfusion scans: Ventilation/perfusion scans, sometimes called a VQ (V=Ventilation, Q=perfusion) scan, is a way of identifying mismatched areas of blood and air supply to the lungs. It is primarily used to detect a pulmonary embolus. The perfusion part of the study uses a radioisotope tagged to the blood which shows where in the lungs the blood is perfusing. If the scan shows up any area missing a supply on the scans this means there is a blockage which is not allowing the blood to perfuse that part of the organ. Myocardial perfusion imaging: Myocardial perfusion imaging (MPI) is a form of functional cardiac imaging, used for the diagnosis of ischemic heart disease.

The oxygenated blood comes from placenta to the fetus through umbilical vein to the fetus’s liver. Then it moves through ductus venosus. This allows some of the blood to go to the liver. But most of this highly oxygenated blood flow to the inferior vena cava and then into the right atrium of the heart. Most of the blood flow across to the left atrium through the foramen ovale.

The heart is a pump that drives the whole circulatory system. It receives and propels blood, rhythmically contracting, forcing the blood through a system of vessels. The hearts action is controlled by the autonomic nervous system. STRUTURE OF THE VEINS, CAPILLARIES AND

Describe the function of the heart, cardiac cycle and circulatory system Function of the heart The heart is a muscular organ that pumps and circulates blood throughout the body via a transport system of arteries and veins and capillaries. As the blood circulates throughout the body it supplies oxygen and nutrients to the tissues as well as removing carbon dioxide and harmful waste products (Tucker, 2015). The structure of arteries Arteries have thick muscular walls and a small lumen passage. According to L. Tucker they are constructed with three layers: • A fibrous outer layer • A middle layer of muscle and elastic tissue • A lining made of squamous epithelial tissue The epithelial lining has a smooth surface to reduce friction and

This concept is taken from Block 4, Module 7 which is entitled as ‘Assessment of cardiovascular system’. The cardiovascular system can also be referred to as the circulatory system. It comprises of the heart and the blood vessels. The major function of the cardiovascular system is to transport nutrients and oxygen to all parts of the body and to remove waste products from the body like carbondioxide. The heart pumps the blood while the blood vessels deliver blood to all body parts.

CARDDIOVASCULAR SYSTEM DEEP VEIN THROMBOSIS Anatomy and physiology Vein is an elastic blood vessel that transports blood from all part of the body to the heart. Vein have four main types, which is pulmonary, systemic, superficial and deep vein. Deep vein located deep within muscle tissue and typically located near the corresponding artery with a same name. Deep vein thrombosis Deep vein thrombosis (DVT) is pathology of cardiovascular system. It happens when the blood clotting in a deep vein of the blood vessel are clumps together and become thick.

Heart rate is a measurement used in a variety of studies for a variety of reasons. The heart’s function is solely to pump blood around the body, so nutrients can be transported and used where they are needed1(p360). Heart rate has been shown to have connections to and be an indicator of general health and abilities thus it is an appropriate variable to consider3,4. The ECG is a trusted and accurate machine used in many studies to determine the heart rate of an individual5,6,7. It has been used as a screening tool for Sudden Cardiac Death with controversial success5.

To use a dialysis machine a tube is inserted into the bloodstream of a patient allowing blood to enter the machine. As shown in Diagram 3, once in the machine the blood flows through tubes and into the dialyzer composed of a semi-porous membrane which works similar to a glomerulus. Blood cells, proteins and other large particles are prevented from passing though while waste products such as urea and salts flow through and are absorbed by sterilised solution called dialysate and are washed away. Dialysate is composed of acidified solution, bicarbonate and purified water. The treated blood is then returned into the bloodstream of the patient.

INTRODUCTION Muscle tissue is one of the four primary tissue types consisting elongated muscle cells that are highly specialized for carrying out certain responsibilities. Muscles are responsible for movement of different parts of the body; posture; respiration; production of body heat; communication; constriction of organs and vessels and contraction of heart. General properties of muscles: Contractility is the ability of muscle to shorten forcefully although its shorten forcefully, it lengthens passively. Excitability is the capacity of muscle to respond to a stimulus. Often the stimulus is from the nerves that we consciously control.

The blood seeps in the sinusoids on its way to the hepatic veins, and then to the vena cava. This filtration is ideal for hepatocytes to filter the blood, process and store nutrients, cleanse, and remove debris. 6. Cirrhosis leads to scarring and increased hydrostatic pressure in the hepatic portal vein. Explain why this increased venous pressure causes net filtration to increase in the hepatic capillaries, leading to ascites (swollen and fluid-filled interstitial space of the abdomen).