Reading...
Play button
Play button
Use LEFT and RIGHT arrow keys to navigate between flashcards;
Use UP and DOWN arrow keys to flip the card;
H to show hint;
A reads text to speech;
42 Cards in this Set
- Front
- Back
|
What are some risk factors for CVD?
|
Age
Sex Ethnicity Hereditary Obesity Diet Alcohol Smoking Stress |
|
|
What are the 3 main components of the CVS?
|
1. Blood Vessels
2. Heart 3. Blood |
|
|
What are the 3 types of blood vessels?
|
1. Arteries
2. Veins 3. Capillaries |
|
|
What are the 3 distinct layers of Arteries?
|
1. Tunica Externa
2. Tunica Media 3. Tunica Intima |
|
|
How many types of arteries are there, what are they called and what are their general functions?
|
There are 3 types of arteries:
1. Elastic Arteries or Conducting Arteries are large vessels. The walls of elastic arteries are extremely resilient because the tunica media contains a high density of elastic fibers and relatively few smooth muscle cells. 2. Muscular arteries distribute blood to the body's skeletal muscle and internal organs. These arteries are characterised by a thick tunica media that contain more smooth muscles than does the tunica media of elastic arteries. 3. Arterioles |
|
|
Why do veins have thinner walls when compared to arteries?
|
Because the pressure is less in veins than it is in arteries.
|
|
|
What are the three layers of the heart?
|
1. Endocardium - inner layer
2. Myocardium - middle muscular layer 3. Epicardium - outer layer |
|
|
What is the pericardium and what is it's function?
|
The pericardium is a fibrous sack surrounding the heart. It secretes fluid to lubricate the hearts movement and attaches the heart to the pleural of the lungs. The two layers of pericardium are called the visceral pericardium (epicardium) and the parietal pericardium.
|
|
|
What are the functions of the heart?
|
To generate blood pressure, routes blood (keeps pulmonary and systemic circulations seperate), ensures one-way blood flow, and regulates blood supply.
|
|
|
What is the equation to measure cardiac output?
|
Cardiac Output = Heart Rate x Stroke Volume
|
|
|
Define blood pressure.
|
Blood pressure is the pressure of the circulating blood against the walls of the blood vessels.
|
|
|
What factors determine blood pressure?
|
Peripheral Resistance and Cardiac Output.
|
|
|
Define peripheral resistance.
|
Peripheral resistance is the resistance to the flow of blood determined by the tone of the vascular musculature and the diameter of the blood vessels.
|
|
|
Define preload.
|
Preload refers to the amount of tension applied to the ventricle muscle prior to contraction.
|
|
|
Define afterload.
|
Afterload is the amount of force required by the ventricles to force open their respective valves to release blood into the system circulation.
|
|
|
How do you calculate the Mean Arterial Pressure (MAP)?
|
MAP = 1/3 PP + DP
PP = Pulse Pressure DP = Diastolic Pressure |
|
|
How is cardiac function regulated?
|
Neural Control.
Hormonal Regulation. Autoregulation. |
|
|
What is the renin-angiotensin-aldosterone system?
|
It is a hormone system that regulates blood pressure and water balance.
|
|
|
Explain the renin-angiotensin-aldosterone system step by step.
|
1. The system is activated by a loss of blood volume or decrease in blood pressure.
2. A decrease in renal perfusion in the juxtaglomerular apparatus stimulates the release of renin from the juxtaglomerular cells in the kidney's. 3. The presence of renin converts angiotensinogen released by the liver, into angiotensin I. 4. Angiotensin I converts into Angiotensin II by the angiotensin-converting enzyme (ACE) found in the capillaries of the lungs. 5. Angiotensin II stimulates the adrenal production of aldosterone, stimulates the secretion of ADH from the posterior lobe of the pituitary gland, stimulates thirst and stimulates CO and causes vasoconstriction. |
|
|
What is Aldosterone?
|
Aldosterone is a mineralcorticoid (corticosteroid hormone) that is secreted by the adrenal cortex. It stimulates sodium and water conservation at the kidneys, thus increasing blood pressure. Aldosterone is secreted in response to the presence of angiotensin II.
|
|
|
What are the functions of Angiotensin II?
|
Angiotensin II has four important functions:
1. It stimulates the adrenal production of aldosterone, causing sodium retention and potassium loss at the kidneys. 2. It stimulates the secretion of ADH from the posterior lobe of the pituitary gland, in turn stimulating water reabsorption at the kidneys and complementing the effects of aldosterone. 3. It stimulates thirst, resulting in increased fluid consumption. 4. And it stimulates CO and causes arteriolar vasoconstriction, in turn elevating systemic BP. |
|
|
What is renin, where is it released from and what is its function?
|
Renin is an enzyme released by the cells of the juxtaglomerular apparatus when renal perfusion decreases. Renin converts angiotensinogen to angiotensin I.
|
|
|
What is ADH, where is it synthesised, where is it released from and what is its function?
|
Anti-diuretic hormone is a hormone synthesised in the hypothalamus and secreted at the posterior lobe of the pituitary gland. It causes water retention at the kidneys and an elevation of BP.
|
|
|
Explain the autoregulation of blood pressure.
|
Autoregulation of blood pressure is a local adjustment of blood flow. The blood flow is influenced by partial pressures of O2 and CO2 and vasoactive substances. If tissues are underperfused, hypoxia results. This results in lactic acid and CO2 build up, causing vasodilation and thus increased perfusion.
|
|
|
How many different types of cardiac cells are there and what are they called?
|
There are two different types of cardiac cells.
1. Myocardial cells are specialised smooth muscle cells 2. Pacemaker cells are clustered into regions that form a set pathway for conduction to follow. They have enhanced automaticity. |
|
|
Define hydrostatic pressure.
|
A pressure exerted by a liquid in response to an applied force.
|
|
|
Define osmotic pressure.
|
The pressure that must be applied to prevent osmosis across a membrane.
|
|
|
Define cardiac reserve.
|
The potential increase in cardiac output above resting levels.
|
|
|
How does Right Heart Failure occur and what are some of the signs and symptoms?
|
RHF can occur through LHF or if it occurs in the absence of LHF, it is most commonly caused by diffuse hypoxic pulmonary disease such as COAD, cystic fribrosis and ARDS. Signs and symptoms include pulmonary hypertension, peripheral oedema and hepatosplenomegaly.
|
|
|
What are the clinical signs and symptoms of CHF (Congestive Heart Failure)?
|
Dyspnoea
Exertional tolerance Pitting oedema Orthopnoea Hypertension Fatigue |
|
|
What does CPAP (Continuous Positive Airway Pressure) do?
|
Redistributes interstitial fluid.
Reduces work of breathing. Increases partial pressure within alveoli. Significantly reduces the need for intubation. Buys time for further therapies. |
|
|
Name some of the causes of a cardiac arrest.
|
AMI
Arrythmia Electrocution Trauma Tension pneumo/haemothorax Electrolyte imbalance Hypothermia Hyper/hypotension Tamponade Toxin - pharmacological or environment Hypovolaemia Hypoglycaemia and other metabolic disturbances. |
|
|
What is a lipid?
|
A lipid is a biomolecule made up of carbon, hydrogen and oxygen. It is not soluble in water due to its nonpolar nature of molecule.
|
|
|
What is atheroma?
|
Atheroma is the abnormal collection of lipids adhering to vessel lumen.
|
|
|
What is a thrombus?
|
A thrombus is an aggregation of platelets, fibrin and clotting factors in response to a vessel wall injury.
|
|
|
What is an embolism?
|
An embolism is a condition in which an embolus travels through the blood stream and becomes lodged in a vessel smaller than its own diameter. Air, gas, fat, imniotic fluid or thrombus (thromboembolism)
|
|
|
What is a lipoprotein?
|
A lipoprotein the the transport medium for lipids as they are not soluble in plasma. Lipoproteins are classified based on the fat they convey and also their density (centrifuge).
|
|
|
What is the difference between Low Density Lipoprotein (LDL) and High Density Lipoprotein (HDL)?
|
Low Density Lipoprotein transports cholesterol to the cells for metabolism whereas High Density Lipoprotein transports cholesterol to the liver for excretion.
|
|
|
What is the pathological consequences of atherosclerosis?
|
Hypertension
Production of ischaemia Sudden vessel obstruction Thrombus/emboli formation Aneurysm |
|
|
What is hypertension, how does it result and what does it lead to?
|
Hypertension is long-term elevated afterload causes chronic elevation of myocardial workload. Hypertension results when there is sustained elevated SVR. Hypertension eventually leads to left ventricular hypertrophy and heart failure.
|
|
|
Name five physiological differences in paediatric's regarding the airway.
|
1. Superoanterior larynx
2. Large head, large occiput 3. Large floppy epiglottis 4. Short neck 5. Children already flexed so extend only to normal position |
|
|
You are called to a 3 year old female with complaints of epistaxis (nasal haemorrhage). what would you expect a normal, healthy 3 year olds vital signs to be (Resp Rate, Systolic BP, Heart Rate)?
|
For a 3 year old:
RR 25-30 SBP 80-100 HR 95-140 |
