The Blood Pressure Oracle

I figured I'd start answering peoples questions about blood pressure, diabetes and home health in general. Over the next few months I'll be writing down various thoughts and answers to questions about these subjects. If you have any questions or comments at all about the subject, please don't hesitate to contact me either directly on this blog or by sending me an email at udiegel@diegeldesign.com.

Just a few thoughts about blood pressure.

At the beginning of the last century, the measurement of arterial pressure is not yet current. On this cliché taken at the Hôpital de la Charité in Paris in 1918, Emile Spengler measures the systolic blood pressure of Charles Laubry, the man who invented the first upper arm blood pressure monitor, used in this picture. Carried out by the manufacturer himself, the gesture is delicate and photogenic.

The moment is not yet banal...


The measurement of blood pressure has now become common place. Anyone can now buy or borrow a home blood pressure monitor that is more accurate than anything that was produced in the last 100 years.

However, it is important to use the device in the correct manner to get accurate and reliable results.

A few basics about blood pressure

We will start by giving you a few undeniable facts and rules about digital blood pressure monitors. These rules are very important but are often forgotten. They will be mentioned again further in my blog, but are worth repeating here.

Your digital blood pressure monitor does not magically transform you into a doctor.

Your blood pressure monitor is probably really easy to use. It probably inflates automatically, makes cool sounds and then incredibly gives you a clinically accurate result. Isn’t that great? It’s child’s play to measure your blood pressure... Well it certainly feels like it... However, your blood pressure monitor is not intended to replace regular medical examinations. It is there to be used together with your doctor as a tool to better manage your blood pressure. Only a physician is qualified to interpret changes in your blood pressure.

When in doubt, ask your doctor for advice.
The first commercially usable blood pressure monitor was manufactured at the turn of the century. In the 70ies digital devices made their appearance and by the 90ies they were commonly available to the untrained public. According to the statistics from our various service departments worldwide, an incredible 94% of all “faulty” devices sent back to manufacturers show absolutely no problem at all and are simply badly used. Faults can range from silly mistakes such as batteries being put in upside down to using the wrong size cuffs. We have even received devices where the batteries were still wrapped up in plastic. Your doctor has been working and studying blood pressure for most of his life and is an expert on the subject. Please ask him to show you how to correctly use your monitor.

Never make adjustments to your medication unless you are advised to do so by your physician.
As mentioned earlier, your blood pressure monitor does not replace a regular medical examination. Your doctor has prescribed medication for you after a careful examination and it can be very dangerous to make your blood pressure fluctuate by changing your medication or by reducing the dosage on your own. If you suspect that your blood pressure medication is wrong because you regularly get low or high blood pressure readings on your device at home, please keep a regular record of your blood pressure for at least three days in a row and then contact your doctor. He will appreciate the fact that you present all the evidence to him in a clear format.

To do so, use a Blood Pressure Passport. There is a multitude of Blood Pressure Passports available out there. You can also download one that I have designed to fit in your wallet on my cardiology company website, www.healthworksglobal.net.

You should know that when the blood pressure is measured by the doctor at his office, there is a multitude of reasons why the blood pressure measured by the doctor can be higher or lower than the one measured at home. One of the most common reasons is what is called “White Coat Hypertension” and occurs when the patient is subconsciously nervous at the medical examination and this makes his blood pressure go up. On average, the systolic pressure will vary by about 30 points during the day, so it is normal for you to have a different blood pressure at home than at the doctor.

This is one of the main advantages of home monitoring, in that it gives you a much better overall picture of your blood pressure over time than the single blood pressure reading that is taken at the doctor’s office.

Do not believe in urban legends or marketing hype when it comes to your health.
When making decisions about your health, question what is commonly believed. There are many “urban legends” about blood pressure, such as salt intake, anti-oxidants in grape seeds and drinking alcohol every day is good for the heart. Although there might be a grain a truth to these kinds of stories, they are not necessarily completely true and are certainly misunderstood. Later in my blog I will set out to demystify some of these stories.

Digital blood pressure monitors are for adults.

There are 2 main obvious reasons why children should not use digital blood pressure monitors. The most important one is that it is sometimes very difficult to find a cuff that is of the correct size for a child. The second reason is much more subjective, but as important as the first. When you measure a blood pressure the cuff has to be inflated to 30 or 40 points higher than the systolic pressure and this can prove to be quite uncomfortable for children, especially infants who cannot express themselves. Often, as a result of this, they move their arm or cry or get stressed, and this negates any diagnostic value of the reading. Children should not use a digital blood pressure monitor unless it is under the strict supervision of an adult.

Another reason why children should not use automatic blood pressure monitors is that the amplitude of the pulse waves generated by a child is very small (an infant has less than 1/2 litre of blood in his body so by definition his blood pressure is quite low) and more often than not an oscillometric (digital) blood pressure monitor will not “hear” the first “Korotkov” sound on which the blood pressure is calculated and will thus give an artificially low result for the blood pressure.

OK, so that's the end of my introduction and basic rules about blood pressure. In the next few episodes, I'll start answering specific questions about blood pressure.

CU soon, and don't hesitate to send me questions about the subject.

Uwe DIEGEL
www.medactiv.com