Showing posts with label Blood Pressure. Show all posts
Showing posts with label Blood Pressure. Show all posts

Jul 2, 2016

Blood Pressure History

In 1628, Dr. Harvey published Exercitatio Anatomica de Motu Cordis et Sanguinis in Animalibus (“On the Movement of the Heart and Blood in Animals”), which was the foundation for work on the circulatory system.

Over 100 years later in 1733, Reverend Stephen Hales recorded the first blood pressure measurement after developing a further understanding of the correlation between the heart and pulse and how it applies to blood pressure and volume.

This new knowledge allowed for the invention of the first sphygmomanometer (blood pressure monitor) in 1881 by Samuel Siegfried Karl Ritter von Basch.

However, it wasn’t until 1905 that Dr. Nikolai Korotkoff discovered the difference between systolic and diastolic blood pressures, further improving the sphygmomanometer by using a cuff that could be placed around the arm to provide equal pressure. Korotkoff discovered the varying sounds within the arteries as pressure was applied and released, and this remains the standard of blood pressure measurement to this day.

Here is what the US National Institution of Health says, Blood pressure can identify potential heart disease, stroke, eye problems, or chronic kidney disease.

All adults should have their blood pressure checked:
- Every 2 years if your blood pressure was less than 120/80 mm Hg at the most recent reading.
- Yearly if your last reading was 120 to 139/80 to 89 mm Hg or if you have high blood pressure, diabetes, heart disease, kidney problems.
Wow, modern medical technology with a silly name and over a hundred years old.

Nov 8, 2013

Blood Pressure

Blood pressure is the intrinsic pressure within your arteries and veins. Your body needs this pressure to adequately supply all your tissues and organs with nutrients. Like the plumbing in your house, adequate pressure is needed, but if that pressure gets too high it causes problems.

High blood pressure is a combination of environmental risk factors and genes. High blood pressure is defined as any systolic pressure (top number) above 140 or diastolic (bottom number) higher than 90.

High blood pressure is not a disease itself, but indicates a risk factor for several other conditions like heart attack, stroke, and kidney failure. The most beneficial way to control blood pressure is naturally. This is because medications that control blood pressure come with serious side effects. These side effects can sometimes be more harmful than the high blood pressure itself.

Things like lack of exercise and bad eating habits can cause a buildup of plaque inside your arteries. Excessive plaque on the interior walls of your arteries makes them smaller, known as “Atherosclerosis”. When the pipes that transport fluid get smaller, the pressure that same volume of fluid exerts goes up. If the blood pressure gets too high, arteries have a greater chance of bursting. Arteries get larger or smaller depending on the needs of the body. Excessive plaque makes this increasingly more difficult for a body to achieve.

A person’s blood pressure can also be too high due to genetics. A landmark study published in Nature in 2011 found 29 genetic variants that affected blood pressure. The authors found any one variant in a gene did not increase risk of hypertension, but people with multiple variants were much more likely to have high blood pressure.

Oct 18, 2013

Blood Pressure

The first known experiment to measure the exact pressure of blood was performed by Stephen Hales on December 1, 1733. He took a live horse, attached a tube to her left crural artery, then allowed her blood to rush through the tube and it rose to a height of 8’3”.

He noted that “when it was at its full height, it would rise and fall at and after each pulse 2, 3,or 4 inches”. The horse bled out, but he performed the experiment on a horse that was about to be put down.

Sep 13, 2013

Blood Pressure

Blood pressure is really just that- the pressure at which blood moves around the body in your arteries. The easiest and least invasive way to test the pressure is to momentarily stop the flow of blood and then slowly allow it to begin again. The pressure at which it begins to flow is the highest pressure the blood exerts on your artery walls.

Medical professionals do this by using a blood pressure meter known as a Sphygmomanometer. They encircle a limb, usually an arm, with a balloon-like device known as a blood pressure cuff. While pumping the cuff up, they use a stethoscope to listen for a heart beat past where the cuff is cutting off blood flow. When they no longer hear the heart beating, they slowly release the pressure while watching the pressure gauge.

When they start to hear the heart beat again, this is the top number of blood pressure, known as systolic pressure. They continue to release the pressure until they once again, no longer hear the heart beating, this is the bottom number of blood pressure, known as diastolic pressure. Together these numbers tell them two things: the pressure that is inside arteries between heartbeats (the bottom number) and the pressure inside arteries when the heart squeezes (the top number).

Different disease processes like coronary artery disease can cause higher than normal blood pressure. Lower than normal blood pressures can be a sign of other disease processes, like shock caused by infection. The difference between top and bottom numbers, or a change in that difference, can also point to specific problems like too much fluid around the heart, not allowing it to work properly.

Combining this information with a person’s heart rate can also tell numerous other things that could be happening. If you have been in a car accident and have a lower than normal blood pressure and higher than normal heart rate, you could be bleeding internally. If you were in another car accident and have an extremely high blood pressure and a low heart rate, you could be bleeding in your brain. High blood pressure is not a disease or illness in and of itself. It is merely a symptom for other problems.

Apr 17, 2013

Salt Myth Debunked

There continues a myth that originated in the 1940s when a professor used salt-reduction to treat people with high blood pressure. Science has since found out that there is no reason for a person with normal blood pressure to restrict salt intake.

Decades of scientific research have failed to prove any benefits of a low-salt diet, and in fact tend to show the opposite. Studies have also failed to prove salt's connection to heart disease.

Salt is essential for life. Natural salt is important to many biological processes, including:
Being a major component of your blood plasma, lymphatic fluid, extracellular fluid, and even amniotic fluid;  Carrying nutrients into and out of your cells;  Increasing the glial cells in your brain, which are responsible for creative thinking and long-term planning; and  helping your brain communicate with your muscles, so that you can move on demand via sodium-potassium ion exchange.

A Scottish Heart Health Study, was launched in 1984 by epidemiologist Hugh Tunstall-Pedoe and colleagues at the Ninewells Hospital and Medical School in Dundee, Scotland. The researchers used questionnaires, physical exams, and 24-hour urine samples to establish the risk factors for cardiovascular disease in 7300 Scottish men. This was an order of magnitude larger than any intrapopulation study ever done with 24-hour urine samples. The BMJ published the results in 1988: Potassium, which is in fruits and vegetables, seemed to have a beneficial effect on blood pressure. Sodium had no effect.

A review published in the Journal of the American Medical Association. University of Copenhagen researchers analyzed 114 randomized trials of sodium reduction, concluding that the benefit for hypertensives was significantly smaller than could be achieved by anti-hypertensive drugs, and that a "measurable" benefit in individuals with normal blood pressure of even a single millimeter of mercury could only be achieved with an "extreme" reduction in salt intake.

Recent studies, including those cited by Harvard University at St. George’s Medical School in London, have shown that potassium rich foods are an essential defense in helping to relieve high blood pressure. Potassium is an essential mineral that enables the body to maintain a healthy fluid and electrolyte balance, while also promoting optimal nerve and muscle functions.

If a person has high blood pressure he or she may become salt-sensitive. Hypertension is actually promoted more by excess fructose than excess salt. This can be relieved by reducing salt intake or increasing potassium intake, because it is the balance of the two that is important. Eating more potassium is probably more important than reducing salt.

Potassium is found in orange colored fruits and vegetables, including pumpkins, carrots, and apricots. Tomatoes and bananas are another source of high potassium. It is also found in artichokes, avocados, broccoli, dark chocolate, spinach, potatoes, yogurt, fish, and and a variety of beans.

May 27, 2011

Blood Pressure Facts

High blood pressure affects about 50 million Americans and 1 billion people worldwide.

Blood pressure measures the force of blood pushing against the walls of the arteries as the heart pumps blood. It is highest near your heart and in the major arteries and lowest in small arteries and capillaries. Because it varies, blood pressure is taken in a standardized place, usually on the inside of your upper arm along the brachial artery.

The upper number, systolic blood pressure, measures the pressure in the arteries when the heart pumps blood throughout the body. The lower number, diastolic blood pressure, is the pressure in the arteries when the heart is relaxing. Healthy blood pressure should be around 120/80 or lower. When the systolic pressure is greater than 120 and the diastolic pressure is greater than 80, patients are diagnosed as having high blood pressure. These levels have recently been lowered from 140/90. Different levels are used for children and adolescents.

High blood pressure is called hypertension and can lead to a number of serious conditions, including coronary heart disease, heart failure, stroke, and kidney failure. Elevated blood pressure levels can make you tired, give you headaches, cause vision problems, and give you an upset stomach, or there can be no symptoms.

Low blood pressure is called hypotension and can result in a decrease in the amount of blood being pumped to the brain resulting in lightheadedness, dizziness, weakness, and fainting. Extremely low blood pressure can also be a sign of a severe cardiac disease and should be taken just as seriously as high blood pressure.

May 13, 2011

Salty Talk

We have seen the advice to reduce salt intake for blood pressure. The American Heart Association encourages people to consume no more than 1,500 milligrams a day of sodium, which is less than half of what people consume. It also says 90% of all Americans will develop hypertension over their lifetime.

Of course there is also scientific evidence that shows increased salt intake keeps blood pressure low for those with low blood pressure and keeps it high for those with high blood pressure. Now there is another new study that raises questions about sodium and its effect on the heart. European researchers followed 3,681 people, average age 40, for about eight years, testing sodium excretion in the urine. They found that systolic blood pressure (the top number) was slightly lower in those who excreted less sodium and those with lower sodium excretion had an increased risk of cardiovascular death. The findings were consistent in participants younger and older than 60 years. So, if you consume less salt you have more chance of cardiovascular death.

The AMA weighs in with, "Lower sodium intake is recommended for people with high blood pressure and people with heart failure."

The Salt Institute is delighted with the findings and I would think Orville Redenbacher is feeling vindicated. Maybe it's time to put a bit more salt on your bacon. . .