It’s one of the most familiar rituals of modern medicine.
Before you can see a doctor, a nurse wraps a plastic cushion around your upper arm, then holds a stethoscope to it while pumping it full of air, squeezing your muscle until just before it’s uncomfortable.
Out of the corner of your eye you see the red mercury jump up and down, but you watch the nurse’s face. As the cuff relaxes, is the nurse smiling or grimacing? Tension grips your heart.
What is Blood Pressure?
To an extent, blood pressure is the natural force of the fluid, your blood, in your arteries driven by your heart as it pumps. However, your blood vessels react to changes in this flow, signaling your brain to keep the pressure within healthy limits.
Therefore, blood pressure also measures how easily your blood flows through your arteries.
Because your heart beats to drive your blood, your pressure rises and falls in regular waves. When your heart beats, the pressure peaks. That’s your systole pressure. When your heart relaxes, the pressure falls. That’s the diastole.
It’s normal for your pressure to fluctuate depending on the time of day and what you’re doing. However, when your pressure remains persistently high that’s a dangerous condition called hypertension. It damages your blood vessels, heart, kidneys, brain and other vital organs. It increases your risk of kidney damage, heart attack, stroke and other serious problems.
Hypertension is one of the most common medical problems of your heart and blood vessels.
Unfortunately, in the early period hypertension often does not cause symptoms. During that time you may not realise you have the problem if you do not get regular checkups from your doctor.
When you go to the doctor or hospital, the nurse uses a sphygmomanometer device to measure your pressure. As the cuff inflates, it cuts off the blood going through your arm’s main artery. When they stop releasing air from the cuff, it relaxes, allowing blood through your main artery at systolic peak. The nurse or doctor hears thumps through the stethoscope. That’s your systolic pressure. It’s measured as millimetres of mercury (mm Hg). When the cuff’s pressure matches your lowest pressure, that’s your diastolic pressure.
It’s commonly recorded as the systolic pressure (such as 140) over the diastolic (such as 90), 140/90, or 140 over 90.
How high is high blood pressure? There’s no ideal figure. You want your pressure to remain within a normal, healthy range. If it’s too low, that indicates other medical problems, and leads to fainting.
Generally, for adults, pressure below 120/80 is normal.
Pressure between 120/80 and 140/90 is high normal.
If your reading is from 140/90 to 180/110, that’s high.
Above 180/110? Very high.
The above figures apply to men and women up to around age 85.
Very old adults over 85 years are often not included in the studies that resulted in the above findings. This article discusses the possibility that in this age group higher blood pressures may lead to increased survival. In studies in Finland and the Netherlands, patients with systolic pressure over 200 survived longer than those with 120 to 140. However, the findings are not conclusive. Older adults are at greater risk from low diastolic pressure causing them to pass out when standing up, especially after eating. This can cause injury from falling.
Therefore, for the very old, many doctors now aim to keep their pressure from 140/90 to 150/85.
Sustained over time, hypertension damages your blood vessels and major organs. It causes atherosclerosis, which clogs your arteries and overloads your heart and blood vessels. The higher your blood pressure and the more it damages your arteries, the harder your heart must work to circulate your blood and the life-giving oxygen and nutrition it supplies to your cells. Over time this weakens your heart, causing shortness of breath and weakness.
Hypertension also damages the blood vessels in your brain, leading them to burst. This cerebral haemorrhage or stroke causes extensive brain damage, sometimes paralyzing people on one side of their bodies.
High blood pressure also damages the delicate blood vessels in your kidneys and eyes.
Therefore, all adults need to know their blood pressure and to keep it normal. Seniors must work closely with their doctors to manage their blood pressure and determine how high is too high.