Maintaining a healthy blood pressure throughout your life is one of the most important things you can do for long-term health and longevity. Whether you're looking up a blood pressure of 57/40 for yourself or a loved one or simply out of your own curiosity, you're taking the right steps by being informed and empowering yourself or someone else to be their own best advocate.
According to the American Heart Association, a blood pressure reading of 57/40 would be considered hypotension, or low blood pressure. Low blood pressure, or hypotension, is defined by a systolic reading (the top number) of less than 90 or a diastolic reading (the bottom number) of less than 60. Low blood pressure generally isn't considered an issue unless it causes symptoms (such as dizziness, light-headedness, or fainting) or unless it drops suddenly.
Okay, now you know how to classify a blood pressure of 57/40, but now what do you do with that information? Read on to learn more or look up another blood pressure reading.
According to the American Heart Association, a normal blood pressure reading is lower than 120/80. While there is no specific number for low blood pressure, most experts say blood pressure is too low when it causes symptoms or drops suddenly. In general, though, low blood pressure can be considered anything under 90/60.
A blood pressure reading of 57/40 is pronounced "57 over 40." You may also see it written colloquially as 57/40 bp.
In a blood pressure reading of 57/40, 57 is called the systolic number and 40 is called the diastolic number. Systolic refers to the part of the cardiac cycle in which the heart contracts and pumps blood from the chambers into the arteries, and diastolic refers to the part of the cardiac cycle in which the heart relaxes and allows the chambers to fill with blood. You may also hear the systolic and diastolic numbers referred to as the top number and the bottom number.
Systolic and diastolic readings are measured in mmHg, which is a unit of pressure equal to the pressure that can support a column of mercury 1 millimeter high. Hg is the chemical symbol for mercury. For a blood pressure reading of 57/40, you would pronounce it "57 over 40 millimeters of mercury."
In a doctor's office, blood pressure is traditionally taken manually by a doctor or nurse with a sphygmomanometer. A sphygmomanometer is a medical instrument with an inflatable cuff and pressure meter or dial. The sphygmomanometer is placed snugly around the upper arm and is inflated by hand, and the doctor or nurse listens to the brachial artery with a stethoscope as they gradually reduce the pressure of the cuff. When the whooshing sound of blood is first heard through the stethoscope, the doctor or nurse makes note of the reading on the pressure meter. This indicates the systolic blood pressure reading. When the sound disappears, the reading on the pressure meter indicates the diastolic pressure reading.
Blood pressure can also be taken at home using a number of a digital devices. They typically consist of an inflatable cuff and digital display and simply work by placing the cuff around the upper arm and pressing a button, after which the cuff inflatess, deflates, and displays a reading. The most popular blood pressure machines for home use are made by Omron, Beurer, and Paramed, amongst many others.
One thing to keep in mind is that blood pressure can vary by time of day and activity level, so if you're taking it at home it's important to check it around the same time each day and rest for a few minutes ahead of time to limit as many variables as possible. It can also be affected by eating.
Blood pressure tends to rise in the hours before waking and then drop in the afternoon and evening before dropping to its lowest point while sleeping, so one popular recommendation is to check it just after waking up and just before bed to identify trends in how it varies from morning until night. Because of this, you might find that if your blood pressure is 57/40 in the morning, it might be lower before bed, and vice versa. Of course, these are just general rules of thumb and may vary by the individual.
If you have an HSA as part of your health insurance plan, you'll be pleased to find that blood pressure monitors, blood pressure cuffs, and wrist blood pressure monitors are all eligible, including smart blood pressure monitors like the offerings from Qardio and Withings.
Sphygmomanometer is pronounced sfig-moh-muh-'nah-mi-ter. Easy!
The following table shows related blood pressure readings because sometimes just one number can make all the difference.
Please note that if a field is blank, it's not an accident—it simply means a record doesn't exist for that particular blood pressure. This could be because going forward or backward would create a blood pressure reading that wouldn't make sense, or because that blood pressure simply doesn't exist in our records.
|← Prev systolic num||Next systolic num →|
|56/40 blood pressure||58/40 blood pressure|
|← Prev diastolic num||Next diastolic num →|
|57/39 blood pressure||57/41 blood pressure|
The information on this page is intended to be an educational reference and is not to be taken as medical advice. If you think you're having a hypertensive or hypotensive emergency, or if you're having any kind of medical emergency, please call 911 immediately.
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