Basics of Blood Pressure | KERA News

Basics of Blood Pressure

Feb 6, 2012

Recent study results by researchers at the University of Exeter indicate measuring blood pressure in both arms instead of one can be a useful indicator of the likelihood of heart trouble. In our KERA Health Checkup, Sam Baker talked about this with Dr. Jane Sadler with Baylor Medical Center at Garland.

Dr. Sadler: Based on this study, 15 millimeters difference in the blood pressures of the left and right arm could indicate a significant increased risk for arterial disease. Specifically, peripheral arterial disease which is disease affecting the legs and the arterial blood flow to our extremities.

Sam: Is this something that had been expected or something that is totally new?

Dr. Sadler: It’s always been encouraged when you first diagnose a patient with high blood pressure to get both the left and the right arm blood pressure. But for continuous rechecking of both arm blood pressures, it is not an office routine. This changes events in the office between the doctor and the patient.

Sam: Just to be clear, what it blood pressure and why is it important?

Dr. Sadler: Well, blood pressure is an indication of the work of the heart, and how hard the heart is working to maintain blood flow to the body. If the heart is working super strong, and has to put out a lot of pressure to get that blood circulating to the body…

Sam:  It’s putting too much strain on your heart.

Dr. Sadler: And not just the heart. It’s the kidneys, it’s the eyes, it’s the blood flow to your lower extremities. It is blood flow to your brain.

Sam: There are two numbers in the blood pressure reading. What do these numbers represent?

Dr. Sadler: Well, the systolic blood pressure is the amount of work or pressure that the heart is requiring to pump the blood out to the body. The diastolic blood pressure kind of reflects the relaxation stage of the heart where, after it’s pumped, there is a certain amount of pressure that is sustained. The normal blood pressure reading that we now like to see in our patients is less than 120 over 80. If someone comes in and there blood pressure is 120s, say 125 over 85, that is designated as pre-hypertension. Over 140 over 90 is designated as hypertension. But let me clarify:  If patient walks into my office and their blood pressure is 146 over 92, I have to remember that is one of an infinite number of blood pressure readings.  What is more important is their blood pressure when they’re not in my office.  The best way to check your blood pressure is to check it twice a day for an entire week.

Sam:  When the blood pressure is high, what can you do to bring that under control?

Dr. Sadler: Well, you, first of all, need to bring it to your doctor, and I request at least ten blood pressure readings. And blood pressure readings as an outpatient are so important because they tell me about what you’re doing on a day-to-day basis.  And at that point, if it’s sustained elevations, then I’m going to encourage you to start some medications, if we have not already started some lifestyle changes.

Sam: If you just want to keep your blood pressure in the normal range, what’s the way to go about doing that?

Dr. Sadler: First of all, reducing your weight, or getting your body mass down to normal. That’s between 18 and  25, based on height and weight. By engaging in what we call the DASH eating plan, where you have more fruits and vegetables, you have low-fat dairy items, you decrease your saturated fats. Physical activity, aerobic exercise 30 minutes a day. And then, moderate alcohol.

Sam: So if we, basically, take care of ourselves and employ some common sense, we should be in good shape.

Dr. Sadler: Not always. In many cases, high blood pressure is hereditary. In over five percent of cases, people can have issues related to excess adrenalin, excess, what we call, sympathetic activity. They may release aldosterone or some hormones that may increase their high blood pressure. They may have issues related to narrowing of the arteries around the kidneys or regulation of salt through the kidneys or many other hereditary issues that even my skinniest vegans can have high blood pressure. And so one thing I do want to emphasize today is that not all high blood pressure or high cholesterol can be managed through exercise and diet modification. Your relationship with your doctor is extremely important.

Dr. Jane Sadler is with Baylor Medical Center at Garland.

For more information:

http://www.nhlbi.nih.gov/health/health-topics/topics/hbp/

http://www.webmd.com/hypertension-high-blood-pressure/default.htm