Antibiotic Prophylaxis
Before Surgery

Do I need to take antibiotics before foot surgery?  

In most cases, probably not.  There are exceptions, though, as discussed below.

Why aren't antibiotics always given before foot surgery?  

Because in most cases, the odds of infection are very low--under 1% if the procedure is performed in a proper sterile environment.  With these sorts of infection rates, using antibiotics routinely before surgery is considered to cause more problems than benefits. 

What kinds of problems does the use of pre-operative antibiotics cause?   

Antibiotics are great drugs, but using them is not without consequence.  They can cause drug interactions with the patient's regular medications, allergic reactions, diarrhea, and a host of other possible side effects to the patient.  

Besides, with infection rates as low as they are, they are not usually needed.  

So what's the harm in using them anyway, just to be safe?  

Well, there are two problems.  First, using antibiotics when you don't need to use them wipes out scores of harmless and even beneficial bacteria in your body.  This can cause the groups of bacteria not targeted by the antibiotics to flourish.  With no competition, they radically increase in number, throwing the body's whole balance out of alignment.  This alone can cause you to become sick.    

The second problem is that indiscriminate use of antibiotics causes the development of so-called "superbugs".

Superbugs?  

There has been much in the news of late about so called "superbugs", new bacteria that have developed resistance to most--and in some cases all--antibiotics.   

The reason these organisms have  developed antibiotic resistance is the overuse of antibiotics for conditions that don't need antibiotics. 

How so?  

When you use an antibiotic, it kills the vast majority of types of bacteria it was designed to kill.  (Prophylactic antibiotics don't aim to kill all bacteria--just the group most likely to cause infection post-operatively.) 

But a very small number of bacteria in the group that is wiped out by the antibiotics may be resistant to the antibiotic, and so may not be killed.  When those organisms reproduce, their offspring will also tend to be resistant to the antibiotic, as will the next generation. 

By this mechanism, we can create large populations of organisms who are resistant to certain antibiotics--so called "superbugs".  The danger is that next time we wish to use an antibiotic, it may be ineffective. 

The most widely-known examples of conditions that shouldn't be treated with antibiotics are the common cold and the flu.  These conditions are caused by viral infections, not bacterial infections.  As antibiotics only work on bacterial infections, the use of antibiotics for these conditions serves no purpose. 

But this can happen anytime antibiotics are used unnecessarily.  As most foot surgery is unlikely to develop an infection, most podiatric physicians don't routinely prescribe pre-operative antibiotics for fear of creating stronger and more virulent organisms.  

So why are antibiotics sometimes given before surgery?    

The idea of using antibiotics before surgery is that we'd like to rid the body of those organisms most likely to cause a post-operative infection.  If we can do this, the wound is less likely to become infected. 

It's just that this view has to be balanced with the fact that antibiotics can cause the patient problems, and the indiscriminate use of antibiotics can create newer, stronger, more virulent organisms that may not only be capable of providing post-operative infections, but that may be resistant to antibiotics altogether. 

So the answer to the question is that we use prophylactic antibiotics in cases where there is more risk to not giving antibiotics than there is to giving them.   

So when is it appropriate to give antibiotics before a procedure? 

The answer to this is somewhat controversial, and decisions are usually made on a case-by-case basis.  But most surgeons tend to use antibiotics on only those patients where infections are particularly likely to develop.  Examples include the following cases:

•  Artificial joint   When artificial joints are put in or replaced, as infection is more likely to develop when foreign material is implanted.  Some extend this list to fixation such as pins, screws, plates, wires, staples, and so forth.  

•  Contaminated cases    Gun shot wounds, lawnmower accidents, and other trauma are already compromised by a break in the skin, the trauma, and the devitalized tissue in the wound, and are therefore more susceptible to infection. 

•  Compromised Host   Diabetics, HIV patients, individuals on steroids, those with systemic disease and other groups will be less likely to fight off infection post-operatively, so may need antibiotic coverage pre-operatively.

•  Prolonged procedures   The longer the case, the more likely a post-operative infection may develop. 

• Procedures involving extensive tissue dissection   The more tissue that is  compromised during a surgery, the more likely a post-operative infection is to develop.   

•  Patients with a shunt    An infection in these cases is particularly dangerous. 

What about patients with valve disease?  My dentist always gives me antibiotics before procedures?  

Patients with a history of valve disease are usually given antibiotics for dental procedures (which are considered inherently "dirty" procedures because of all the bacteria in the mouth), but the American Heart Association recommends that antibiotic prophylaxis before most podiatric surgeries--which are considerably cleaner procedures than are dental surgeries--is not typically advised. 

What antibiotics are most commonly used before surgery? 

Choices vary, but the most frequent antibiotic choice for prophylaxis before foot surgery is Ancef given intravenously.  In patients with an allergy, Vancomycin or Clindamycin are most typically chosen. 

How soon before the procedure are prophylactic antibiotics usually given?

When antibiotics are given pre-operatively, the desire is to have blood levels at their peak at the time of the surgery.  Hence, prophylactic antibiotics are usually given less than an hour before surgery.