Abstract
Minimizing the risk of periprosthetic joint infection (PJI) is of interest to all surgeons performing hip and knee arthroplasty. Among the most critical factors to reducing the risk of infection include the use of pre-incisional antibiotics, appropriate skin preparation with clippers (as opposed to a razor for hair removal) and the use of an alcohol-based skin preparation. Host factors are also likewise critically important including obesity, diabetes, inflammatory arthritis, renal insufficiency, skin disorders and patients who are otherwise immune-compromised. If modifiable risk factors are identified, it would seem reasonable to delay elective surgery until these can be optimised.
One other factor to consider is the nutritional status of the patient. In a study of 501 consecutive revisions, we found that serological markers suggestive of malnutrition (albumin, transferrin or total lymphocyte count) were extremely common in the revision population. Specifically, among patients who presented for treatment of a chronic infection, 53% (67 of 126) had at least one marker for malnutrition. The prevalence of serological markers of malnutrition was lower (33%) in the group of patients undergoing revision for an aseptic reason suggesting that malnutrition was a risk factor for septic failure (p < 0.001 and OR 2.1). Interestingly, malnutrition was most common among patients of normal weight but was also common among obese patients (so-called “paradoxical” malnutrition). What was more disturbing, however, that of those patients undergoing an aseptic revision, serum markers of malnutrition were associated with a 6x risk of acute postoperative infection complicating the patient's aseptic revision.
At our center, we also have studied the use of dilute betadine at the end of the case, prior to wound closure, in an attempt to decrease the load of bacteria in the wound. In a retrospective review the prevalence of acute postoperative infection was reduced from just under 1% (18/1862) to 0.15% (1 of 688; p = 0.04). It is critical that the betadine utilised be STERILE and the dilution we use is 0.35% made by diluting 17.5cc of 10% povidone-iodine paint in 500cc of normal saline. Although this is a retrospective review, it does suggest a benefit and we have not seen any problems associated with its use.
