Cardiovascular System Research Paper
Cardiovascular System
_____________________________________________________________________
The total length of you cardiovascular system stretches an amazing 96,000km(60,000 miles) - more than twice around the Earth
________________________________________________ (Human Body 2001)
Gas Exchange, Transport & Organization of the Body
Contents
1. What is the Cardiovascular system
2. The composition and function of the heart.
The structure and function of the organs and tissues of the heart.
3. The composition and function of the Blood Vessels
. The structure and function of the organs and tissues of the blood vessels
4. The …show more content…
composition and function of the Blood.
The structure and function of the tissues in respect to the blood.
5.
References and Bibliography
1) The Cardiovascular System
The Cardiovascular system is constructed of the heart, blood vessels (arteries, veins and smaller vessels) and the blood.
The body needs this system to transport oxygen, nutrients and waste to the body 's tissues to maintain homeostasis (active process that maintains a constant internal environment despite external changes). (Tortora 1996)
The illustration shows the transport of blood to the body. The arteries and arterioles (Red) and veins and venules (Blue). However, there are some exceptions: the Pulmonary veins, the Pulmonary arteries and the capillaries.
The body also has two types of circulations:
The Pulmonary circulation takes deoxygenated blood from the heart to the lungs, picks up oxygen and goes back to the heart.
The oxygenated blood is then transported to the rest of the body before returning to the heart via the Systemic circulation. During this process blood goes to the stomach, intestines, spleen and pancreas, these have their own set of blood vessels (Hepatic portal vein and artery and the mesenteric veins) where absorption of nutrients and removal of toxins and waste takes place. (Ross & Wilson 2011)
2) The
Heart
_________________
The heart is a powerful muscle, and is located in the Thoracic cavity, just to the left of the sternum. The heart is made of Cardiac muscle called the Myocardium. There are two nodes (Sinoatrial & Atrioventricular) situated in the right atrium. (Tortora 2006. pg 590). The heart consists of four chambers: two upper chambers called the atria and two thicker lower chambers called the ventricles. A strong muscular wall, called the septum, divides the left side chambers from the right. There are four one-way valves (Mitral, Aortic, Pulmonary, and Tricuspid). There is an adipose layer covering sections of the outer surface of the heart. Major blood vessels attach to the heart. (Tortora 2006)
Blood Vessels of the Heart are: Superior vena cava, Inferior vena cava, Pulmonary artery, Pulmonary veins and the Aorta. They carry blood into and out of the heart, however the heart has its own blood supply called the coronary arteries. (Tortora 1996 pg. 587)
The Pericardium is a triple layered sac that separates the heart from the lungs and chest wall. It is made from a tough, inelastic, dense irregular connective tissue and prevents the heart from overstretching, provides protection and is a source of smooth movement when the heart beats. (Tortora 1996)
The Heart 's wall has three layers of tissue. The outmost one is called the epicardium. It is composed of a single sheet of squamous epithelial cells, and is overlying delicate loose connective tissues. Which provides structural support, binds the heart to its neighbouring structures and protects the heart’s internal structures? (Tortora 1996)
Myocardium (middle layer) consists of cardiac striated muscle; it constitutes for the bulk of the heart and is three times thicker on the left side of the heart, as it is responsible for pumping the oxygenated blood around the body.
Though the Cardiac muscle is involuntary, it is unable to rest, working constantly. It has distinctive features: its fibres are branched with thick myosin and thin actin proteins( responsible for muscle contraction).(Ross & Wilson 2011, Tortora 1996) and has an abundant number of mitochondria, so when one is resting another one is working, thus, enabling constant aerobic respiration and prevention of muscle fatigue. (Buzzle2013).
The innermost part of the three walls is called Endocardium and has a thin layer of endothelium flattened cells that line the inside of the heart and its connecting valves. ). (Ross & Wilson 2011, Tortora 1996)
Inside the Heart
The heart is divided into a left and a right side by a thick muscle called the Interventricular septum (consists of myocardium tissue) each side has an upper chamber, Atrium and an inferior chamber, ventricle. Between these are valves. ). (Tortora 1996)
Valves of the heart
There are 4 valves in the heart that allow blood to move in 1 direction; left side: the aortic, mitral (bicuspid). The right side: tricuspid and pulmonary valves. These valves allow blood to enter the heart and prevent back flow into the chambers.
(Ross & Wilson 2011)
The heart beats around three
Billion times in the average person 's life (Human Body 2001)
________________________________________
The function of the heart
The autonomic nervous system controls the heart beat by triggering a neurotransmitter in the heart called the acetylcholine. This triggers theSinoatrial (natural pacemaker of the heart) and Atrioventricular nodes of the heart via an electrical action and sends an electrical pulse to the bundle of his (inside Interventricular septum), intern makes the ventricles contract which pushes blood through the semi-lunar valves. There is an adipose layer that covers sections of the heart, to act as an insulator to prevent the heart from short circuiting itself. (Buzzle 2013 & Tortora1996)
Blood flow through the Heart
Veins carry deoxygenated blood from the body into the superior and Inferior vena cava they then empty the blood into the right atrium. The atrium contracts and blood then passes through the Tricuspid valve into the right ventricle, the Tricuspid valve then shuts to prevent back flow. The ventricle then contracts and the pulmonary valve opens and allows blood to flow through it then closes, the pulmonary artery then transports the blood to the lungs where gaseous exchange takes place; CO2 released and oxygen is absorbed.
The oxygen rich blood is then taken to the Pulmonary veins and enters the left atrium, the atrium then contracts and blood is forced into the left ventricle through the Mitral valve, this then closes. The Myocardium then contracts forcing the blood out of the left ventricle through the Aortic valve, this then closes forcing the blood into the Aorta and around the body via arteries to the capillaries, where gaseous exchange takes place. (Human Body 2001)
However, this process is done in two stages the Diastolic and Systolic and is recognised as Heart beat:
1. Blood enters the left and right atrium
2. The nodes initiate the next stage where the atria contract pushing blood into the ventricles.
3. The ventricles then contract forcing blood out of the heart and around the body. (Human Body 2001)
3). Blood Vessels
The size of blood vessels varies
Enormously, from a diameter of about 25 mm (1 inch) in the aorta to only 8 μm in the capillaries. . (Human Body 2001)
Blood vessels are responsible for transporting blood from the lungs to the heart then to the tissues of the body, finally returning back to the heart and lungs.( Buzzle 2013)
The thickness of blood vessel walls varies, being largest in the arteries, and only a single cell thick in the capillaries. Despite the range of sizes the structure of the blood vessel walls has common features. (Buzzle 2013). Tunica intima (endothelium) - simple squamous epithelial cells which are a single layer of flattened cells, whose role is protection, filtration, secretion and the absorption from direct contact with blood. A middle layer called the Tunica media is constructed of smooth muscle and elastic fibres; these regulate the constriction or dilatation of the vessels themselves in response to chemical and nervous stimuli. The Tunica externa is composed of connective tissue which provides structural support and anchorage for the vessels and they all have a Lumen- blood filled space. (Tortora 2006) Elastic and muscular arteries and arterioles Although they also possess fibrous collagen tissue and smooth muscle, about half of their structure is composed of elastic fibres. The largest arteries (Aorta) have a higher content of smooth muscle and elastic fibres to allow the vessels to expand when blood is ejected into them from the heart and to constrict again as blood flows out. Muscular (distributing) arteries ' tunica media is denser to control blood pressure. Arterioles are the vessels at the end of the arteries. They have very thick walls in relation to their diameters. They are controlled by Sympathetic nerves.
They transport oxygenated blood around the body. Except the Pulmonary artery. (Blakemore, C. & Jennet,S..2001)
(A) Endothelium (flattened epithelial tissues)
(B) Internal elastic lamina (connective tissue rich in protein) (C) Tunica Media (Smooth muscle & elastic fibres)
(D) External elastic media
(E) Tunica adventitia (Protein sheath containing nerves and blood vessels)
Capillaries
Capillaries are a complex system of branching blood vessels between arterioles and venules (microscopic veins).
They allow passage of substances between blood and the fluids in the body 's tissues. They are vast in numbers and consist of a single layer of endothelial cells, with microscopic spaces between each cell, thus allowing solutes in the blood, including salts, glucose, and dissolved oxygen, to pass into the tissues, and metabolic waste, including CO2, to pass back into the blood. . (Tortora 2006)
Veins
Approximately 70% of the entire
Blood volume is contained within
The veins. (Human Body 2001)
_____________________________________
Blood returns from the tissues to the heart along veins. Veins have valves which ensure that blood travels in the correct direction therefore preventing back flow. However, they need the activity of muscles to keep blood flowing within.
They can accommodate quite large changes in their volume, because they collapse when empty. Sometimes the valves may cease to function, causing veins to distend abnormally and permanently. This is the cause of varicose veins. (Ross & Wilson 2011)
4) Blood
Blood makes up around 8% of the weight of a human body.(Human Body 2001) Blood contains Erythrocytes (red blood cells), Leukocytes (white blood cells) and Thrombocytes (platelets). They are suspended in liquid called plasma (55%). Blood is a connective tissue and connects the body systems together by bringing oxygen, nutrients, hormones , and removal of wastes. Blood has a major function to maintain homeostasis by transporting nutrients and defending off diseases. (Smart T 2001) It helps regulate body temperature, pH, . Blood is divided into group. There are currently around 30 recognized blood types (or blood groups). The more simplified systems are categorized under blood types O, A, B and AB and be either rhesus - or + (science kids 2013) Erythrocytes are biconcave to increase surface area in order to maximise the absorption of oxygen from the lungs. They don 't require a nucleus; however they contain a protein called haemoglobin which contains iron that combines with oxygen(oxyhaemoglobin). Transport of oxygen from the lungs to the body 's tissues and removal of CO2 via capillary exchange.
Erythrocytes develop in bone marrow and circulate in the body for around 120 days. This begins in the kidneys, when oxygen levels drop they releasing a hormone, this hormone then travels to the red marrow in flat bones(e.g. Sternum)where production of Erythrocytes are stimulated. .(Tortora 2006)
Leucocytes are an important part of the body’s immune system. They defend against certain bacteria, viruses, cancer cells, infectious diseases and other unwanted materials. Each one has a specific function. (science kids 2013)
Thrombocytes help blood clot in order to limit bleeding when your skin is cut. As well as delivering important substances to our cells, blood also helps take away unwanted waste products.
Blood clots can occasionally have negative effects, if they form in blood vessels going to the brain they can cause a stroke while clotting in a blood vessel going to the heart can lead to a heart attack. (Buzzle 2013)
Blood plasma
Makes up 55% of the total blood volume. It is a straw coloured liquid which holds the following components in a suspension: 92% water - carries heat
1% various electrolytes - maintains correct concentration of salts
7% gases, nutrients, proteins, glucose and hormones - corrects PH of blood and cells. (Tortora 2006& Ross & Wilson 2011 & Freeman 2007)
Idiopathic (or Immune) thrombocytopenic purpura (ITP)
Is the medical term for a low platelet count. Platelets are essential in the formation of blood clots to prevent haemorrhage - bleeding from a ruptured blood vessel.
It is a disorder where antibodies coat platelets and then destroy them; therefore platelets are lost quicker than they are replaced. ITP appears like a pin prick bleeding under the skin and becomes very painful, if not treated hospitalisation may occur.
When bleeding occurs, muscles in the vessel wall contract and reduce blood flow. The platelets then stick to each other and hold on to the vessel wall. The coagulation factors are then activated, resulting in blood clotting and preventing loss of blood. (Kiasco 2013, NHS 2013)
The platelet count in the blood is normally between 150 and 400 million per ml of blood, in ITP it is less than 2o million. There is a particularly high risk of bleeding once the platelet count drops below 10 million per ml resulting in a serious haemorrhage, this can occur at the back of the eye (retina), sometimes threatening sight, or even potentially fatal if spontaneous bleeding occurs inside the head, or from the lining of the intestines.(Harrison & Machin 2012)
What causes ITP?
False thrombocytopenia - some platelets stick together or a clot in a blood sample.
Congenital thrombocytopenia - Rare inherited disorders (e.g. Bernard Soulier syndrome - lifelong symptoms may occur)
Defective platelet production - Platelet making cells fail to produce enough.
Metabolic disorders, e.g. kidney failure.
Abnormal platelet: viral infections such as HIV.
Bone marrow infiltration, e.g. leukemia, lymphoma and the side effects from treatments such as chemotherapy.
Diminished platelet survival- Platelet numbers fall if they are removed from the circulation more rapidly than they are produced.
Decreased antibodies in response to drugs, blood transfusion or another disease, e.g. glandular fever.
Loss of platelets from the circulation- Massive blood transfusion or exchange.
Enlarged spleen causes platelets to be stored and not distributed into the blood stream.
Treatment
Acute ITP starts suddenly and usually follows a viral illness in a child. Acute ITP may require no treatment, if platelets are above 20 million. It usually improves and rarely comes back.
Chronic ITP develops over time and lasts longer and more common in adults. If treatment is needed then a course of steroids are given over a period of time, or lifetime course of medication is administered as well as a lifestyle change. (NHS 2013, Harrison & Machin 2012)
Atherosclerosis
This is a progressive, degenerative disorder, where the artery walls become thicker and a loose their elasticity. The arteries become narrow because of accumulation of plaque deposits (fatty core with a fibrous tip), excessive cholesterol and fats in the blood. If blood roughens these deposits, +then platelets and blood adhere to them and then embeds to the side of the arteries, thus gradually building up and impeding blood flow through the lumen. If the blood builds up a great deal it may form a blood clot called a thrombus. If this blood clot breaks away, it is called an embolus. This embolus can block one of the smaller arteries for example the coronary arteries in the heart, resulting in a heart attack, or an artery in the brain causing a stroke. (NHS. 2013, Tortora 2006 & Human Body 2001)
Risk factors for Atherosclerosis
Although many factors contribute, people who eat a diet high in saturated fats and cholesterol have a higher risk of developing it. Also people who have diabetes, hypertension, obesity, people who smoke or who have hereditary factors.
However, people with high cholesterol are more at risk, because the cholesterol is not water soluble and will adhere quicker to the plaque deposits causing deterioration of the arteries therefore shortening a human’s life span.
Treatment
Medication can be given to reduce Hypertension and cholesterol lowering tablets. However, reducing dietary intake of saturated fats and cholesterol, eat less red meat (beef, pork and Lamb) and high fat dairy products (butter, hard cheese and whole milk) is a start. (Tortora 2006 & Doohan J 2000).
_____________________________________________________________________
The total length of you cardiovascular system stretches an amazing 96,000km(60,000 miles) - more than twice around the Earth
________________________________________________ (Human Body 2001)
Gas Exchange, Transport & Organization of the Body
Contents
1. What is the Cardiovascular system
2. The composition and function of the heart.
The structure and function of the organs and tissues of the heart.
3. The composition and function of the Blood Vessels
. The structure and function of the organs and tissues of the blood vessels
4. The …show more content…
composition and function of the Blood.
The structure and function of the tissues in respect to the blood.
5.
References and Bibliography
1) The Cardiovascular System
The Cardiovascular system is constructed of the heart, blood vessels (arteries, veins and smaller vessels) and the blood.
The body needs this system to transport oxygen, nutrients and waste to the body 's tissues to maintain homeostasis (active process that maintains a constant internal environment despite external changes). (Tortora 1996)
The illustration shows the transport of blood to the body. The arteries and arterioles (Red) and veins and venules (Blue). However, there are some exceptions: the Pulmonary veins, the Pulmonary arteries and the capillaries.
The body also has two types of circulations:
The Pulmonary circulation takes deoxygenated blood from the heart to the lungs, picks up oxygen and goes back to the heart.
The oxygenated blood is then transported to the rest of the body before returning to the heart via the Systemic circulation. During this process blood goes to the stomach, intestines, spleen and pancreas, these have their own set of blood vessels (Hepatic portal vein and artery and the mesenteric veins) where absorption of nutrients and removal of toxins and waste takes place. (Ross & Wilson 2011)
2) The
Heart
_________________
The heart is a powerful muscle, and is located in the Thoracic cavity, just to the left of the sternum. The heart is made of Cardiac muscle called the Myocardium. There are two nodes (Sinoatrial & Atrioventricular) situated in the right atrium. (Tortora 2006. pg 590). The heart consists of four chambers: two upper chambers called the atria and two thicker lower chambers called the ventricles. A strong muscular wall, called the septum, divides the left side chambers from the right. There are four one-way valves (Mitral, Aortic, Pulmonary, and Tricuspid). There is an adipose layer covering sections of the outer surface of the heart. Major blood vessels attach to the heart. (Tortora 2006)
Blood Vessels of the Heart are: Superior vena cava, Inferior vena cava, Pulmonary artery, Pulmonary veins and the Aorta. They carry blood into and out of the heart, however the heart has its own blood supply called the coronary arteries. (Tortora 1996 pg. 587)
The Pericardium is a triple layered sac that separates the heart from the lungs and chest wall. It is made from a tough, inelastic, dense irregular connective tissue and prevents the heart from overstretching, provides protection and is a source of smooth movement when the heart beats. (Tortora 1996)
The Heart 's wall has three layers of tissue. The outmost one is called the epicardium. It is composed of a single sheet of squamous epithelial cells, and is overlying delicate loose connective tissues. Which provides structural support, binds the heart to its neighbouring structures and protects the heart’s internal structures? (Tortora 1996)
Myocardium (middle layer) consists of cardiac striated muscle; it constitutes for the bulk of the heart and is three times thicker on the left side of the heart, as it is responsible for pumping the oxygenated blood around the body.
Though the Cardiac muscle is involuntary, it is unable to rest, working constantly. It has distinctive features: its fibres are branched with thick myosin and thin actin proteins( responsible for muscle contraction).(Ross & Wilson 2011, Tortora 1996) and has an abundant number of mitochondria, so when one is resting another one is working, thus, enabling constant aerobic respiration and prevention of muscle fatigue. (Buzzle2013).
The innermost part of the three walls is called Endocardium and has a thin layer of endothelium flattened cells that line the inside of the heart and its connecting valves. ). (Ross & Wilson 2011, Tortora 1996)
Inside the Heart
The heart is divided into a left and a right side by a thick muscle called the Interventricular septum (consists of myocardium tissue) each side has an upper chamber, Atrium and an inferior chamber, ventricle. Between these are valves. ). (Tortora 1996)
Valves of the heart
There are 4 valves in the heart that allow blood to move in 1 direction; left side: the aortic, mitral (bicuspid). The right side: tricuspid and pulmonary valves. These valves allow blood to enter the heart and prevent back flow into the chambers.
(Ross & Wilson 2011)
The heart beats around three
Billion times in the average person 's life (Human Body 2001)
________________________________________
The function of the heart
The autonomic nervous system controls the heart beat by triggering a neurotransmitter in the heart called the acetylcholine. This triggers theSinoatrial (natural pacemaker of the heart) and Atrioventricular nodes of the heart via an electrical action and sends an electrical pulse to the bundle of his (inside Interventricular septum), intern makes the ventricles contract which pushes blood through the semi-lunar valves. There is an adipose layer that covers sections of the heart, to act as an insulator to prevent the heart from short circuiting itself. (Buzzle 2013 & Tortora1996)
Blood flow through the Heart
Veins carry deoxygenated blood from the body into the superior and Inferior vena cava they then empty the blood into the right atrium. The atrium contracts and blood then passes through the Tricuspid valve into the right ventricle, the Tricuspid valve then shuts to prevent back flow. The ventricle then contracts and the pulmonary valve opens and allows blood to flow through it then closes, the pulmonary artery then transports the blood to the lungs where gaseous exchange takes place; CO2 released and oxygen is absorbed.
The oxygen rich blood is then taken to the Pulmonary veins and enters the left atrium, the atrium then contracts and blood is forced into the left ventricle through the Mitral valve, this then closes. The Myocardium then contracts forcing the blood out of the left ventricle through the Aortic valve, this then closes forcing the blood into the Aorta and around the body via arteries to the capillaries, where gaseous exchange takes place. (Human Body 2001)
However, this process is done in two stages the Diastolic and Systolic and is recognised as Heart beat:
1. Blood enters the left and right atrium
2. The nodes initiate the next stage where the atria contract pushing blood into the ventricles.
3. The ventricles then contract forcing blood out of the heart and around the body. (Human Body 2001)
3). Blood Vessels
The size of blood vessels varies
Enormously, from a diameter of about 25 mm (1 inch) in the aorta to only 8 μm in the capillaries. . (Human Body 2001)
Blood vessels are responsible for transporting blood from the lungs to the heart then to the tissues of the body, finally returning back to the heart and lungs.( Buzzle 2013)
The thickness of blood vessel walls varies, being largest in the arteries, and only a single cell thick in the capillaries. Despite the range of sizes the structure of the blood vessel walls has common features. (Buzzle 2013). Tunica intima (endothelium) - simple squamous epithelial cells which are a single layer of flattened cells, whose role is protection, filtration, secretion and the absorption from direct contact with blood. A middle layer called the Tunica media is constructed of smooth muscle and elastic fibres; these regulate the constriction or dilatation of the vessels themselves in response to chemical and nervous stimuli. The Tunica externa is composed of connective tissue which provides structural support and anchorage for the vessels and they all have a Lumen- blood filled space. (Tortora 2006) Elastic and muscular arteries and arterioles Although they also possess fibrous collagen tissue and smooth muscle, about half of their structure is composed of elastic fibres. The largest arteries (Aorta) have a higher content of smooth muscle and elastic fibres to allow the vessels to expand when blood is ejected into them from the heart and to constrict again as blood flows out. Muscular (distributing) arteries ' tunica media is denser to control blood pressure. Arterioles are the vessels at the end of the arteries. They have very thick walls in relation to their diameters. They are controlled by Sympathetic nerves.
They transport oxygenated blood around the body. Except the Pulmonary artery. (Blakemore, C. & Jennet,S..2001)
(A) Endothelium (flattened epithelial tissues)
(B) Internal elastic lamina (connective tissue rich in protein) (C) Tunica Media (Smooth muscle & elastic fibres)
(D) External elastic media
(E) Tunica adventitia (Protein sheath containing nerves and blood vessels)
Capillaries
Capillaries are a complex system of branching blood vessels between arterioles and venules (microscopic veins).
They allow passage of substances between blood and the fluids in the body 's tissues. They are vast in numbers and consist of a single layer of endothelial cells, with microscopic spaces between each cell, thus allowing solutes in the blood, including salts, glucose, and dissolved oxygen, to pass into the tissues, and metabolic waste, including CO2, to pass back into the blood. . (Tortora 2006)
Veins
Approximately 70% of the entire
Blood volume is contained within
The veins. (Human Body 2001)
_____________________________________
Blood returns from the tissues to the heart along veins. Veins have valves which ensure that blood travels in the correct direction therefore preventing back flow. However, they need the activity of muscles to keep blood flowing within.
They can accommodate quite large changes in their volume, because they collapse when empty. Sometimes the valves may cease to function, causing veins to distend abnormally and permanently. This is the cause of varicose veins. (Ross & Wilson 2011)
4) Blood
Blood makes up around 8% of the weight of a human body.(Human Body 2001) Blood contains Erythrocytes (red blood cells), Leukocytes (white blood cells) and Thrombocytes (platelets). They are suspended in liquid called plasma (55%). Blood is a connective tissue and connects the body systems together by bringing oxygen, nutrients, hormones , and removal of wastes. Blood has a major function to maintain homeostasis by transporting nutrients and defending off diseases. (Smart T 2001) It helps regulate body temperature, pH, . Blood is divided into group. There are currently around 30 recognized blood types (or blood groups). The more simplified systems are categorized under blood types O, A, B and AB and be either rhesus - or + (science kids 2013) Erythrocytes are biconcave to increase surface area in order to maximise the absorption of oxygen from the lungs. They don 't require a nucleus; however they contain a protein called haemoglobin which contains iron that combines with oxygen(oxyhaemoglobin). Transport of oxygen from the lungs to the body 's tissues and removal of CO2 via capillary exchange.
Erythrocytes develop in bone marrow and circulate in the body for around 120 days. This begins in the kidneys, when oxygen levels drop they releasing a hormone, this hormone then travels to the red marrow in flat bones(e.g. Sternum)where production of Erythrocytes are stimulated. .(Tortora 2006)
Leucocytes are an important part of the body’s immune system. They defend against certain bacteria, viruses, cancer cells, infectious diseases and other unwanted materials. Each one has a specific function. (science kids 2013)
Thrombocytes help blood clot in order to limit bleeding when your skin is cut. As well as delivering important substances to our cells, blood also helps take away unwanted waste products.
Blood clots can occasionally have negative effects, if they form in blood vessels going to the brain they can cause a stroke while clotting in a blood vessel going to the heart can lead to a heart attack. (Buzzle 2013)
Blood plasma
Makes up 55% of the total blood volume. It is a straw coloured liquid which holds the following components in a suspension: 92% water - carries heat
1% various electrolytes - maintains correct concentration of salts
7% gases, nutrients, proteins, glucose and hormones - corrects PH of blood and cells. (Tortora 2006& Ross & Wilson 2011 & Freeman 2007)
Idiopathic (or Immune) thrombocytopenic purpura (ITP)
Is the medical term for a low platelet count. Platelets are essential in the formation of blood clots to prevent haemorrhage - bleeding from a ruptured blood vessel.
It is a disorder where antibodies coat platelets and then destroy them; therefore platelets are lost quicker than they are replaced. ITP appears like a pin prick bleeding under the skin and becomes very painful, if not treated hospitalisation may occur.
When bleeding occurs, muscles in the vessel wall contract and reduce blood flow. The platelets then stick to each other and hold on to the vessel wall. The coagulation factors are then activated, resulting in blood clotting and preventing loss of blood. (Kiasco 2013, NHS 2013)
The platelet count in the blood is normally between 150 and 400 million per ml of blood, in ITP it is less than 2o million. There is a particularly high risk of bleeding once the platelet count drops below 10 million per ml resulting in a serious haemorrhage, this can occur at the back of the eye (retina), sometimes threatening sight, or even potentially fatal if spontaneous bleeding occurs inside the head, or from the lining of the intestines.(Harrison & Machin 2012)
What causes ITP?
False thrombocytopenia - some platelets stick together or a clot in a blood sample.
Congenital thrombocytopenia - Rare inherited disorders (e.g. Bernard Soulier syndrome - lifelong symptoms may occur)
Defective platelet production - Platelet making cells fail to produce enough.
Metabolic disorders, e.g. kidney failure.
Abnormal platelet: viral infections such as HIV.
Bone marrow infiltration, e.g. leukemia, lymphoma and the side effects from treatments such as chemotherapy.
Diminished platelet survival- Platelet numbers fall if they are removed from the circulation more rapidly than they are produced.
Decreased antibodies in response to drugs, blood transfusion or another disease, e.g. glandular fever.
Loss of platelets from the circulation- Massive blood transfusion or exchange.
Enlarged spleen causes platelets to be stored and not distributed into the blood stream.
Treatment
Acute ITP starts suddenly and usually follows a viral illness in a child. Acute ITP may require no treatment, if platelets are above 20 million. It usually improves and rarely comes back.
Chronic ITP develops over time and lasts longer and more common in adults. If treatment is needed then a course of steroids are given over a period of time, or lifetime course of medication is administered as well as a lifestyle change. (NHS 2013, Harrison & Machin 2012)
Atherosclerosis
This is a progressive, degenerative disorder, where the artery walls become thicker and a loose their elasticity. The arteries become narrow because of accumulation of plaque deposits (fatty core with a fibrous tip), excessive cholesterol and fats in the blood. If blood roughens these deposits, +then platelets and blood adhere to them and then embeds to the side of the arteries, thus gradually building up and impeding blood flow through the lumen. If the blood builds up a great deal it may form a blood clot called a thrombus. If this blood clot breaks away, it is called an embolus. This embolus can block one of the smaller arteries for example the coronary arteries in the heart, resulting in a heart attack, or an artery in the brain causing a stroke. (NHS. 2013, Tortora 2006 & Human Body 2001)
Risk factors for Atherosclerosis
Although many factors contribute, people who eat a diet high in saturated fats and cholesterol have a higher risk of developing it. Also people who have diabetes, hypertension, obesity, people who smoke or who have hereditary factors.
However, people with high cholesterol are more at risk, because the cholesterol is not water soluble and will adhere quicker to the plaque deposits causing deterioration of the arteries therefore shortening a human’s life span.
Treatment
Medication can be given to reduce Hypertension and cholesterol lowering tablets. However, reducing dietary intake of saturated fats and cholesterol, eat less red meat (beef, pork and Lamb) and high fat dairy products (butter, hard cheese and whole milk) is a start. (Tortora 2006 & Doohan J 2000).