The City Water Tower and Your Water Tower
Have you ever experienced a “water failure”? That is, have you ever turned on your faucet and found that no water came out of it? If you get your water from a municipal water system, the answer is probably “No.” At least not unless it was intentionally turned off to repair a leak somewhere along the line. Or should it get hit by a tornado and knocked over, no water, or very little water, will come out your faucet downhill in the town.
Like water, blood runs downhill. To combat edema or a bleeding vein, the bottom of the hill must be your heart. It takes a pump to get water from the town’s reservoir (or in the body your legs) all the way back up to the top of the tower where it can start its trip back down to the town again, where now rather than having to be pumped, it can simply flow downhill. To prevent the flow of blood in your veins downhill to your legs, you legs must be elevated higher than your heart. When there is a leak (bleeding) somewhere in the water main or any of the feeder pipes (your veins), the water tower has to be shut down. Just as when a tornado knocks the tower on its side, when you lie down and elevate your legs, it is like turning over the City water tower.
When a person is standing, gravity affects the blood flow in our veins. It is also responsible for the pressure in all of our blood vessels. This pressure is called hydrostatic pressure and this is the pressure that has to be overcome to get blood back uphill to your heart. Hydrostatic pressure is overcome by (1) the blood pressure in your arteries as blood is pumped from your heart through the capillary beds forcing blood back uphill and (2) by the calf and thigh venous muscle pumps.
The dictionary gives us a long, complicated definition of hydrostatic pressure but, simply put, hydrostatic pressure is the weight of a column of fluid. The taller the column (your height), the greater the pressure at the bottom of the column (your legs). The taller the City water tower the higher the pressure in your faucet.
Because of this pressure at the bottom of the column—or in your legs—it is important to control any fluid by turning over the column of fluid whether it is water when there is a leak in the water line or blood that fails to return back up the veins going from your legs.
In summary of our comparison of the human body to a city’s water tower, the taller you are or when you stand the higher the pressures are at the ankle. When you lie down, the pressure in the veins lowers. When you elevate your legs, the pressure lowers even more just as when the city water tower falls over and you have no water pressure in the faucets in your house.
The range of ambulatory venous pressure values (ten toe lifts) in normal limbs and limbs with venous disease are listed below:
- Normal limb: Ankle pressure 15 to 30 mm of mercury. Remember with no ambulation and just standing pressure is 90 mm of mercury at the ankle and sitting is 60 mm of mercury at the ankle.
- One with varicose veins with competent but non-refluxing perforating veins, 25 to 40 mm of mercury
- Varicose veins with incompetent perforating veins, 40 to 70 mm of mercury
- Deep vein valvular incompetence, 55 to 85 mm of mercury
- Deep valvular incompetence with a proximal obstruction, 60 to 70 mm of mercury
- Proximal obstruction with a competent popliteal vein, 25 to 60 mm of mercury
If you have really bad problems, you do not have to memorize these numbers, but you absolutely have to understand the principles of the above to help control edema in your lower legs or you will develop severe complications–ulceration. The only way we can combat these numbers is with (1) proper elevation of the legs and (2) significant grade compression stockings.
It is also important to understand that the largest organ of the human body is the skin. The end organ of venous disease is the skin.
In one study of 251 limbs, the instances of skin ulceration (active or healed) in relation to ambulatory venous pressure are as follows:
|RELATIONSHIP BETWEEN AMBULATORYVENOUS PRESSURE AND THE INCIDENCE OFSTASIS ULCERATION|
|Ambulatory Venous Pressure(mmHg)||Instance of ulceration and %|
|Less than 30||Zero (0)|
|31 to 40||12%|
|41 to 50||20%|
|51 to 60||38%|
|61 to 70||57%|
|71 to 80||68%|
|Greater than 80 mm of mercury||73%|
What can be done to help if I have severe problems?
- Stop the reflux that can be stopped (superficial veins)
- Compression stockings to counteract as much of the high venous pressure as possible
- Turn over your water tower–at least partially upside down–at least 30 minutes to 1 hour three times daily
- The bottom of the hill is your heart and water and blood run downhill.
Fortunately, the most common veins that reflux and cause ulcers are the superficial veins that can be lasered, treated with radiofrequency ablation or removed. Even if both superficial and deep veins reflux, treating the superficial veins is a major help.
Bleeding varicose veins
Over time one concern of patients with bulging varicose veins, and rightly so, is, “What if it starts to bleed?”
Bleeding from a varicose vein is profound because the downward pressure (hydrostatic pressure) present in varicose veins can be tremendous. Blood will squirt a long distance from the vein making you think an artery has been cut. The reason for bleeding from a varicose vein is really quite simple. Some veins as they stretch under pressure cause thinning of the skin over them and they will look like a blue blister. Now the only thing separating the blood inside the vein from the rest of the world is a thin-walled vein and a few thin skin cells. These may spontaneously burst or a small scratch or injury to the site can break down this thin barrier. Sometimes this happens by simply softening the skin in the area by soaking and washing with a cloth in a shower or bath. Other times people will find that shaving the legs results in profuse bleeding with just a small nick or slight trauma from bumping into something. Whatever the cause, it can be very scary if you do not know what to do.
So what should you do? First, remember your body is like a water tower. Just like the town’s water tower when it is down and little or no water reaches your faucet downhill you must turn over your water tower by getting your leg above the level of your heart and reversing the hydrostatic pressure. Lie down and put your foot up the wall or on a chair or even lie on the bathroom floor with your foot elevated, but get your leg higher than your heart. If someone is with you, have them apply pressure to the area for 15 or 20 minutes to allow time for a clot to begin to form after the pressure is reduced. Still you may have to go to the emergency room to have a stitch placed. If you are alone and can reach the area, apply pressure on the area yourself but do not allow the bleeding area to drop lower than your heart. If the bleeding does not slow or stop and you are alone and need to call for help, crawl to the phone. Do not stand up as this will increase the pressure and blow out any clot that might have begun to form and the bleeding will start all over again.
Once you have the bleeding under control, and whether or not you had to go to the emergency room, call your doctor and make an appointment. Most likely you will be referred to a vascular specialist to determine the cause of your varicose veins and begin treatment. You may require sclerotherapy of this vein to seal it shut before any workup is begun to determine a diagnosis and treatment is started to correct the underlying problem.
Proper leg elevation
Keeping in mind our example of a town’s water tower, you are reminded again of how water and blood run downhill and the bottom of the hill should be your heart. The same simple principle is true when it comes to helping control edema of your lower extremities with the use of compression stockings and proper elevation of your legs.
It should first be noted that there are two groups of patients who may not be able to elevate their legs. First are the patients who have moderate to severe congestive heart failure (CHF) and may become short of breath when lying flat. Your doctor may need to adjust the dosage of your diuretic (water pill) to help get rid of the excess water as it returns to your heart. Second are the patients with moderate to severe peripheral arterial disease (PAD) who will have pain in their feet and legs when they elevate their legs because the arterial blood now has to go “uphill” against gravity to get to the feet. You will need to be evaluated to see if the arterial blood flow to your feet can be improved. Letting your feet hang down all day so they do not hurt creates a problem with swelling of your ankles. Helping one problem aggravates another.
Simple elevation of the legs above heart level for 30 minutes to 1 hour two or three times per day can reduce edema and improve blood flow in the veins. Additionally, improving blood flow can speed healing of venous ulcers. If an ulceration is present on the lower leg, a swollen leg will not heal.
Most important is to find out why your veins are not working properly. There is other conservative treatment, such as compression stockings, or minimally invasive procedures that can help you return to a better quality of living and reduce the possibility of developing further, more harmful problems such as venous stasis ulcers or blood clots.
Non-invasive venous duplex Doppler ultrasound testing is done in the office both supine and standing. We always check an artery in your foot to be sure there is adequate blood flow to your foot. This testing does not use any needles and it is painless.
We hope the information on these pages is both informative and helpful, but it is intended for education only. Please do note that no web site, no matter how much information is shared, can replace a consultation with your doctor and a vascular specialist. Medical technology and treatment are continually improving and evolving so before making any decision on treatment, it is always advisable to see your doctor first for a comprehensive evaluation of your vascular disease and other medical conditions.
At the Vascular Center of Wichita Falls, we work closely with your other physicians. If you have concerns about your arteries or veins, contact us. A referral is not necessary to make an appointment.