To prophylax or not to prophylax – that is and remains the question for total joint patients

Physicians pride themselves on taking a scientific, evidence-based approach to therapeutic questions. Unfortunately, in many clinical situations the evidence is scant or limited. One common and thorny situation is whether to give antibiotic prophylaxis to total joint patients undergoing dental work. I’ve long been uncertain on this one, especially since the American Heart Association revised its guidelines for antibiotic prophylaxis of infective endocarditis in 2007.

So, will antibiotics prevent prosthetic joint infections in patients undergoing dental work?

To assist busy clinicians facing this question, the American Academy of Orthopaedic Surgeons and the American Dental Association just released their evidence-based guideline, “Prevention of Orthopaedic Implant Infection in Patients Undergoing Dental Procedures.”  It can be found at http://www.aaos.org/research/guidelines/PUDP/PUDP_guideline.pdf.

The guideline is the product of an extensive review of available evidence, and runs to over 300 pages. Unfortunately for front line clinicians, the bottom line is vague. The key recommendation states: The practitioner might consider discontinuing the practice of routinely prescribing prophylactic antibiotics for patients with hip and knee prosthetic joint implants undergoing dental procedures.

If one of our patients with a total knee or hip replacement, or a local dentist, asks our opinion on whether antibiotic prophylaxis is needed, it looks like we can now definitively state we “might consider” saying no. If that is too equivocal, we could respond that “routinely prescribing” prophylactic antibiotics might not be necessary.

To further cloud the issue, this guideline is issued with a Grade of Recommendation: Limited, which means “the quality of the supporting evidence that exists is unconvincing, or that well-conducted studies show little clear advantage to one approach versus another.”So the experts pull their punches even more.

Hmmm. What to do, what to do?

My musings above probably sound more snarky than I intend. A bunch of very smart physicians and dentists spent a lot of time reviewing all available evidence on this question. The fact they could not provide more definitive guidance simply reflects the current science. But it does leave practicing clinicians in an unresolved situation. Previous consensus guidelines on this question generally recommended antibiotics within two years of joint replacement, or anytime for a patient who is immune compromised or has significant comorbidities. The newly released guideline seems to now open the door slightly to not giving antibiotic prophylaxis routinely. Certainly, anytime we prescribe antibiotics to our patients, we are subjecting them to a small level of risk. It is also true oral bacteria are transiently found in the blood stream on virtually a daily basis. These factors weigh against antibiotics.

When all is said and done, getting our patients’ consent is probably the safest thing to do. Briefly present the pros and cons on antibiotic prophylaxis and let the patient decide. If the patient defers the decision to their clinician, it is a judgment call. As is so much in medicine. In some respects, medicine really is more art than science.

Richard Fleming, M.D.

Comments are closed.