Originally printed September 2012

I recently had several women inmates at one of my jails complain that their legs were swollen and request a “water pill” to get rid of the swelling. This happens now and again at the jails and seems to occur in waves; I will see a bunch of requests for water pills to help leg swelling, then nothing for a while, then it recurs. Having the suspicious mind that I do, I often suspect that the real reason for the water pill request is weight loss.Once, in fact, an inmate admitted that the women in her dorm were having a weight loss contest and that was why we were seeing so many complaints of constipation and water retention.

However, some patients have simply been taught by other medical providers, either in corrections or out, that the reason that their legs swell at the end of the day is “fluid retention” and the solution is “water pills.” Both notions are wrong for the vast majority of the patients I see.  The cause of their ankle swelling is NOT fluid retention and diuretic “water pills” will not help them.

I Do Not Mean Patients With CHF

Now I am not talking here about patients with congestive heart failure (CHF).  CHF is caused by a heart that has been so seriously weakened by heart disease that it cannot pump blood efficiently.  Consequently, fluid accumulates somewhere in the body.   Failure of the left side of the heart results in fluid accumulating the lungs, called pulmonary edema.  Such patients have difficulty breathing.  Less common is right-sided heart failure, in which excess fluid pools in the periphery and theoretically could cause ankle swelling.   However, such patients are usually easy to spot because they have a history of heart disease. They have cardiologists. They are usually on several heart medications, not just a diuretic. They usually have pulmonary edema leading to respiratory complaints as well.  Other chronic medical conditions can result in peripheral edema, as well.  These include kidney disease, liver disease, and arterial disease.  What these patients have in common is that they are all chronically ill, with other signs and symptoms of their disease beyond simple ankle swelling.  I am not talking about these patients.

I am talking instead about relatively young and healthy patients who complain of swelling in their ankles. This is an entirely different problem with an entirely different cause.  I myself have this problem. Back when I worked in the ER, at the end of a long shift, I would have big divots in my ankles from my socks. This is a common problem for people who are on their feet at work for long periods. Most of my colleagues in the ER had the same problem. It is not caused by fluid overload. In fact, my colleagues and I were more likely to be a little dehydrated at the end of an ER shift than fluid overloaded.  And, of course, none of us were in congestive heart failure.

When a patient complains of swollen ankles, my first job as a clinician is to make sure they do not have one of these chronic disease processes.  Fortunately, that is usually pretty easy.  No history of CHF, MI, kidney disease?  No “Red Flag” physical findings?  Normal activity level?  Done.

Gravity Is the Culprit

The real cause of this swelling is gravity. Over time, gravity gradually pulls fluid downward to the lowest, most dependent places of the body. This process is called “Dependent Edema.” This process occurs when we stand but also occurs when we sit for long periods, because the legs hang beneath the heart, and gravity works its inexorable way.  So the first thing to teach patients with dependent edema is that process is caused by gravity, not fluid overload.

The second thing to teach them is what to do about it.  That involves knowing the three mechanisms the body uses to get excess fluid out of the legs against the pull of gravity.

Three Ways To Resist the Pull of Gravity

1.  The first mechanism is using gravity itself to reverse the flow. We do this naturally when we sleep with our legs level with our hearts.  Overnight, gravity pulls the fluid out of the legs that had accumulated there during the day. You can achieve the same effect by elevating your legs periodically.  One of my partners in the ER had a particularly bad time with ankle swelling. Every single time he sat down to dictate a chart or to read medical records, his feet were up on the counter.  Inmates with dependent edema should be taught to elevate their legs periodically during the day.

2.  The second mechanism the body uses to get fluid out of the legs is the rhythmic contraction/relaxation of the leg muscles, particularly the gastroc-soleus muscles in the calf. As these muscles contract, they squeeze venous blood up the legs back to the heart. So the more patients walk around, the less their ankles will swell. Conversely, the more patients stand or sit, the more their ankles will swell.  And one solution for fluid that has accumulated in the ankles is to contract those calf muscles:  take a walk around the pod.  Do toe raises.  Combine this with elevation by putting your feet in the air and writing the alphabet with your toe.  Everything will help.

3.  The final mechanism the body has to get fluid out of the legs against the flow of gravity is the natural tone of the leg veins. Unfortunately, this tone is decreases with age, which is why I did not have a problem with swollen ankles when I was in my 30’s, but I do now. Fortunately, however, there is a way to artificially restore venous tone in the legs:   by wearing compression stockings, like TED hose. Compression stockings increase the resting pressure in the lower legs, thus allowing less fluid to accumulate.  TED hose are rarely medically necessary, but in some cases are fabulous.

Finally, diuretics will not be helpful in treating these cases of dependent edema.  The cause is not fluid overload.  And even if the patient takes diuretics, the process of gravity driven dependent edema will continue. Don’t prescribe diuretics for this condition.

Putting It All Together

An inmate requests to be seen in medical clinic for swollen ankles.  She tells me that she has been prescribed “water pills” for this in the past.  The clinical encounter will probably follow this course:

1.  I make sure that the patient does not have a chronic medical condition that is causing the swelling.  I do this via history and exam.

2.  I tell the patient the true cause of the condition.  It is not “fluid overload.”  The diagnosis is Dependent Edema, and it is caused by gravity.

3.  I tell the patient that “water pills” are not appropriate therapy for this condition.

4.  I tell the patient the three ways she can improve the swelling:  Elevate her legs, walking and other kinds of leg exercise, and compression.

5.  In some cases (older patient, perhaps, with more severe edema and maybe signs of venous stasis), I may offer to order compression hose.  I have found, however, that most patients will not wear compression hose, especially men.

How do you handle complaints of swollen ankles in your facility?  Please comment!