Question

Can you please answer these questions also. Thanks in advance

1. A patient suffering from hypertension may receive drugs that decrease the heart's output, dilate arterioles, or increase urine production. In each case, how would the drug treatment help relieve hypertension?

2. Heavy smokers often develop abnormally high blood pressure. The nicotine in tabacco in a potent vasoconstrictor. Explain the connection between these two facts, including what kind of blood vessels are likely affected.

3.Before antibiotics were available, it wasn't uncommon fro people in the United States (and elsewhere) to develop rheumatic fever. This disease develops after the patient is infected by Streptococcus pyroxenes, a hemolytic (red blood cell-destroying) bacterium. The infection can trigger an inflammation that ultimately damages valves in the heart. How much this disease affect the heart's functioning? What kinds of symptoms would arise as a consequence?

4. The highly publicized deaths of several airline travelers led to warnings about "economy-class syndrome". The idea is that economy-class passengers don't have as much leg room as passengers in more costly seating, so they are more likely to sit essentially motionless for long periods on flights-conditions that may allow blood to pool and clots from the legs. This condition is called deep-vein thrombosis, or DVT. In addition, low oxygen levels in airplane cabins may increase clotting. If a clot gets large enough to block blood flow or breaks free and is carried to the lungs or brain, it can lethally block an artery. There could be a time lag between when a clot forms and health problems, so an air traveler who later develops DVT might easily overlook the possible connection with a flight. Studies are now under way to determine whether economy-class travel represents a significant risk of DVT. Given what you know about blood flow in the veins, explain why periodically getting up and moving around in the plane's cabin during a long flight may lower the risk that a clot will form.

Answer 1

1. Anything that decreases cardiac output, also decreases blood pressure, because there is less pressure on the vessel walls.

Vasodilation is the widening of blood vessels. When blood vessels dilate, the flow of blood is increased due to a decrease in vascular resistance. Therefore, dilation of arterial blood vessels (mainly the arterioles) decreases blood pressure.

Increase in urine volume will lead to dehydration and a fall in blood pressure. When the kidney makes more urine, the amount (volume) of blood that fills the arteries and veins decreases, and this lowers blood pressure.

2. The nicotine in cigarettes and other tobacco products makes the blood vessels get narrower and as a result, the heart beats faster, which makes the blood pressure get higher. Nicotine is a stimulant, speeding up the heart by about 20 beats per minute with every cigarette, it raises blood pressure, is a vasoconstrictor - which means it makes arteries all over the body become smaller making it harder for the heart to pump through the constricted arteries.

3. Rheumatic fever is an inflammatory reaction that can develop as a complication of a Group A streptococcal infection. Every part of the heart, including the outer sac (the pericardium), the inner lining (the endocardium) and the valves may be damaged by inflammation caused by acute rheumatic fever. However, the most common form of rheumatic heart disease affects the heart valves, particularly the mitral valve.

4. the formation of blood clots in veins deep within the legs or deep vein thrombosis occurs during (or just after) a long aeroplane flight, especially in economy class (tourist class) where there is the least space allotted per passenger and where there is very less room for leg movement. Other risk factors contributing to the syndrome include lower oxygen pressure and dehydration. In order to prevent it, the passengers should drink lots of water and move their legs by walking whenever possible and by periodically flexing and extending their ankles, knees, and hips to minimize the risk of the economy class syndrome.