Knee-high graduated compression socks are used to aid in the prevention of varicose & spider veins, swelling, blood pooling, night cramps, leg fatigue, and to relieve foot & leg pain as nurses & health care providers spend hours standing during a 12-hour shift.

Why prolonged standing is bad: Blood flow & your Calf muscle

With each beat of your heart, your body pumps freshly oxygenated blood through your arteries, while “old” blood is pumped back to your lungs and heart through your veins.

When you stand, due to the additional resistance of gravity, the blood that flows down to your legs and feet, needs additional assistance to get back to your heart and lungs for re-oxygenation and detoxification.

The superficial veins, deep veins, bicuspid valves, and the calf-pump, all work together to move blood back to your lungs. The primary driving force of this entire process comes from your calf muscle pump. However, it’s the walking motion that activates your calf pump as the contraction of your calf muscle pushes blood up. When your calf muscle relaxes, this allows blood to refill in empty vein segments and the next walking step keeps the cycle going.

Standing, by contrast, doesn’t activate the powerful calf muscle pump since the muscle needs to be contracted to pump blood. This means that the veins of the lower leg have to do the work on their own and that requires them to create high amounts of pressure. Extended periods of high pressure through these veins can cause them to stretch, which also allows blood to flow backward, as the one-way-valves are no longer “air-tight” due to the veins being stretched beyond the valves.

This results in edema, swelling, blood pooling, inflammation, varicose veins, and spider veins, along with a host of other health problems.

compression socks & activation of your calf-muscle-pump

Knee-length graduated compression socks work by applying external compression that is controlled due to the socks being graduated. The compression sock is tightest at the ankle/foot and gradually lessens in pressure towards the knee.

Also, external pressure activates the calf pump, which along with the enhanced pressure gradient speeds up blood flow back to your heart

When you must stand for extended periods, the best way to activate the calf-pump is through external compression, which has the same activating action as walking. This is why compression socks are worn by nurses and shift workers who spend hours standing on their feet.

The amount of blood pumped out of your heart in 1-minute is known as cardiac output. Your cardiac output is 20-30% lower when standing as opposed to lying down (about venous return).

Compression socks & varicose veins

One of the main reasons, besides relieving leg/foot pain that nurses wear compression socks is to help avoid getting varicose or spider veins.

A team of researchers in Denmark followed a group of nearly 5,700 Danish workers over 12 years and determined that workers who stood for more than 6+ hours of their work-shift were at significantly greater risk for varicose veins than those who stood for less than 4 hours.

As nurses must stand for hours, especially OR and ER nurses, who could be standing for over 12-hours straight, a simple, cost-effective, and easy way to keep the blood flowing properly and prevent varicose veins is by wearing compression socks.

Standing: How long is too long?

According to the Canadian Centre for Occupational Health and Safety:

So what is the “ideal” amount of time spent standing per day?

According to Dutch ergonomic guidelines for prolonged standing:

A 2007 study from the Netherlands studied nearly 250 operating room (OR) nurses in 16 dutch hospitals with the “goal of being able to develop a targeted injury prevention policy.”

In certain situations, like when performing surgery, it’s impossible not to stand. Here are some recommendations from the Dutch study:

• Take a micro-break or change posture - “During microbreaks and changes of posture, the muscles have the chance to relax. The flow of blood is restored, oxygen is supplied, and waste matter is carried away and joints can once again be lubricated.”

• Rotate job duties

• Use a stool

While this study made some good recommendations, it was mostly focused on policy changes. In the real world of accidents and chaos, it can be impossible to slip out for a micro-break or rotate jobs, which is why many nurses choose to wear knee-high compression socks.

Jesse is the Director of Pedal Chile and lives in Chile’s Patagonia (most of the year). Jesse has a Master of Science in Health & Human Performance and a Bachelor of Science in Kinesiology. Hobbies: MTBing, snowboarding, meditation, reader of non-fiction, researcher, & compression sock wearer.

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Sources for “Why Do Nurses Wear Compressions Socks”

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2. Johnson, S. (2002). Compression hosiery in the prevention and treatment of venous leg ulcers. Journal of Tissue Viability, 12(2), pp.67–74.

3. Meijsen, P. and Knibbe, H.J.J. (2007). Prolonged Standing in the OR: A Dutch Research Study. AORN Journal, 86(3), pp.399–414.

4. Raju, S. and Neglén, P. (2009). Chronic Venous Insufficiency and Varicose Veins. New England Journal of Medicine, 360(22), pp.2319–2327

5. Shankar H., K. (2017). Clinical study of varicose veins of lower limbs. International Surgery Journal, 4(2), p.633.

6. Tüchsen F., Hannerz, H. and Burr, H. (2005). Prolonged standing at work and hospitalisation due to varicose veins: a 12 year prospective study of the Danish population. Occupational and Environmental Medicine, 62(12), pp.847–850

7. Waters, Thomas R, and Robert B Dick. “Evidence of health risks associated with prolonged standing at work and intervention effectiveness.” Rehabilitation nursing : the official journal of the Association of Rehabilitation Nurses vol. 40,3 (2015): 148-65. doi:10.1002/rnj.166

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