Antibiotic Prophylaxis for Patients with Joint Replacements

Yes, the protocol has changed again.

By Kevin M Keating, DDS, MS

There are more than 1 million total joint replacement surgeries performed annually in the United States, of which approximately 7 percent are to replace failing prosthetic joints.1 Infections of total joint replacements usually result in failure and lead to the replacement of the prosthesis. Recognizing the risks to prosthetic joints associated with blood born bacteremias, the American Association of Orthopaedic Surgeons (AAOS) and American Academy of Orthopaedic Surgeons have modified their recommendations for preoperative prophylactic antibiotics for medical and dental procedures.

In February of 2009 the AAOS presented their most current recommendations for antibiotic prophylaxis in patients with total joint replacements. The revised guidelines recommend that patients with total joint replacements should receive prophylactic antibiotics appropriate for the type of medical or dental procedure that is anticipated. The prophylactic antibiotics are given to minimize the hematogenous spread of bacteria to the prosthesis. The antibiotic recommended in these newer guidelines is specific for the common bacteria associated with the medical or dental procedure. Dermatologic procedures would focus on staphylococci and oral procedures would require antibiotics more appropriate for streptococci.

Unlike the prior guideline wherein prophylaxis was recommended only for the two years following placement of the prosthetic joint, the current AAOS recommendation again recommends the need for preoperative antibiotic prophylaxis for the life time of the patient. The American Medical Association (AMA) guideline as we know recommends prophylaxis for two years, but those most closely associated with joint failure — orthopedic surgeons — have published their recommendations which will supersede those of the AMA.

In light of the American Heart Association's (ADA) reasons for modification of their recommendations for prophylactic antibiotics for those at risk for bacterial endocarditis, there appears to be controversy about the relative risks associated with dental treatment versus other sources of oral cavity induced bacteremias. Since there is controversy over the perceived and real risks of bacteremias originating in oral cavity, the ADA and the AAOS have appointed a joint task force of experts to develop an evidence-based position paper on antibiotic prophylaxis recommendations for dental treatment for those patients with total joint replacement.

It is my understanding this joint position paper is anticipated to be completed in 2012. Until this joint position paper is developed and disseminated, it is strongly recommended that the premedication protocols of the American Academy of Orthopaedic Surgeons should be used for managing patients with total joint replacement.

The AAOS position paper also states that the health care professional who is planning treatment should do so in consultation with the patient's surgeon on the need for prophylactic antibiotics and confirm if that surgeon has specific recommendations that are different than those of the guidelines. This is also the recommendation of The Dentists Insurance Company (TDIC). TDIC further recommends obtaining written confirmation of the surgeon's recommendations for prophylaxis. They suggest utilizing a faxable Medical Consultation form that can be returned to your office from the surgeon's office confirming both the need for prophylaxis and the preferred prophylactic antibiotic regimen for that patient.

Using a faxable Medical Consultation form to obtain a medical recommendation to utilize or not utilize prophylactic antibiotics is necessary for legal reasons. Art Curley, a prominent Malpractice Defense attorney and consultant for TDIC states that not to do so can be considered practicing medicine without a license should you decide to premedicate without consultation.2

It should be pointed out so that there is no confusion. The AAOS guideline points out that patients with pins, plates and screws, or other orthopedic hardware that is not within a synovial joint are not at increased risk for hematogenous seeding by microorganisms.

Below is the table from the AAOS guidelines listing those for whom they recommend prophylactic antibiotics. I also have reproduced their antibiotic regimen which is not the same as other prophylactic antibiotic regimens.

 

TABLE 1 
Patients at Potential Increased Risk of Hematogenous Total Joint Infection3
  • All patients with prosthetic joint replacements
  • Immunocompromised/immunosuppressed patients
  • Inflammatory arthropathies (e.g., rheumatoid arthritis, systemic lupus erythematosus)
  • Drug-induced immunosuppression
  • Radiation-induced immunosuppression
  • Patients with co-morbidities (e.g., diabetes, obesity, HIV, smoking)
  • Previous prosthetic joint infections
  • Malnourishment
  • Hemophilia
  • HIV infection
  • Insulin-dependent (Type 1) diabetes
  • Malignancy
  • Megaprostheses


TABLE 2 
AAOS Recommended Protocol for Dental Procedures likely to cause Bacteremia3

Cephalexin
Cephradine                       2 grams PO                    1 hour prior to treatment
Amoxicillin

Note: There is no alternative antibiotic suggested for those patients who are allergic to penicillin and cephalosporin antibiotics. Consequently, one must consult with the patient's surgeon and obtain written confirmation as to what alternative antibiotic therapy should be utilized.

The faxable Medical Consultation form suggested by TDIC is a valuable tool for facilitating this consultation. The benefit of the fax form is it allows for direct communication in a timely fashion and does not require pulling the physician or you away from patient care. For those insured by TDIC, one can obtain the Medical Consultation form online or by calling the TDIC advice line at 800-733-0634.


REFERENCES:

  1. Number of Patients, Number of Procedures, Average Patient Age, Average Length of Stay - National Hospital Discharge Survey 1998-2005. Data obtained from: U.S. Department of Health and Human Services; Centers for Disease Control and Prevention; National Center for Health Statistics.

  2. Art Curley, Esq., The Dentists Insurance Company malpractice attorney consultant, Personal Communication. January 2011.

  3. Information Statement: Antibiotic Prophylaxis for Bacteremia in Patients with Joint Replacements, American Academy of Orthopaedic Surgeons: February 2009, Revised June 2010.