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What do compression stocking measurements mean?

This question was asked in Deerfield Beach, Florida and has 9 answer(s) as of 08/13/2013.
Compression stockings are measured in mmHg. What does this mean?


Doctors Answers (9)

mmhg stands for millimeters of mercury, which is a unit of measurement for pressure. Compression stockings have pressure points and as you move and walk they help to increase blood flow in the legs. We recommend graduated compression stocking 20-30 mmhg to help with varicose and spider veins.

The mmHg is pressure of mercury and is used to measure the amount of pressure on the superficial venous system. Medical grade compression has two numbers. At the lower ankle/calf, the pressure is high and this eases off to the lower number higher in the leg. This facilitates return of blood up the leg by compressing superficial veins and forcing the blood into the deep vein for return. It also reduces the fluid build up in the lower legs if you are prone to swelling. Hence we can have 15 - 20, 20- 30, or 30-40 mmHg. 15-20 is considered subclinical. Medical strength is 20-30 and up to 50-60 in extreme cases.

Compression hose or stockings are worn to reduce the total volume of venous blood retention (reduces the outward stretching of the veins) and increase the flow of venous blood return upward from the legs to the heart, while not having sufficient compression to inhibit arterial circulation. Medical grade hose comes in several compression ranges from the lighter compression of 15-20 mm/Hg and moderate 20-30 mm/Hg to the higher compression of 30-40 mm/Hg. The compression is not uniform but is a gradient compression with the tightest portion (the larger of the 2 numbers) at the ankles and the least compression at the upper thighs. If the hose are waist high, then the waist will have minimal compression and only act to help keep the hose in place but are not tight. Compression is measured as the force that would lift a column of mercury a set number of millimeters in a glass column, as this was once a common instrument and way to measure barometric air pressure.

We measure the stocking to fit a patient in terms of size in centimeters around a set landmarks on the leg. The prescribed strength is in mmHg or millimeters of mercury which is the pressure of compression.

mmHg is the pressure applied to your ankle and lower leg by the compression stocking. The larger the number, the greater the pressure.

The rated compression for graduated compression support hose is the pressure on the ankles. The pressure is less as one goes up the leg from the ankle. Arterial blood pressure is measured in mm of Mercury in the same manner as we measure the pressure from support hose. The pressure is expressed as the pressure exerted by a column of Mercury in a vertical glass cylinder. Until fairly recently, this was a much more accurate way of measuring pressures than other techniques and it remains the standard for measurement of pressure.

Compression stocking have the most pressure at the toe and then gradually the pressure decreases as it goes up the leg. This allows the return of blood to be forced upward to the heart and does not act as a tourniquet.

It tells you your size if you are talking measurements. If you are talking strengths that is the tightness of the stocking in pressure terms. 20 to 30 meaner 30 at the feet and 20 at the knee or thigh. It is graduated pressure.

Standard human physiology pressures are measured in millimeters of mercury (periodic table Hg), which reflects the pressure 1 atmosphere of pressure at sea level = 14.7 psi = 760 mm Hg. 30-40 mm Hg pressure is the amount needed to effectively compress the superficial veins in the leg while standing. There you go!

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