In this era of diminishing health-care resources and increasing accountability, it is our duty as orthopaedic surgeons to minimize the risk of complications and to optimize the outcomes for our patients. The prevention of surgical site infection has been of particular interest recently. Two recent articles in The Journal of Bone and Joint Surgery by Kim and coauthors and by Schwarzkopf and associates address these issues.
In the paper by Kim et al., the authors instituted a screening and eradication program for methicillin-resistant Staphylococcus aureus in patients undergoing elective orthopaedic operations at the New England Baptist Hospital in Boston. This program was initiated on the basis of multiple previous studies that identified Staphylococcus aureus as an organism that is carried in the nasal passages of patients1-3. In addition, staphylococci continue to be the most common causes of infection after orthopaedic operations. It also has been shown that intranasal mupirocin is the most effective method of eradicating intranasal Staphylococcus aureus4. In this study, the authors wished to investigate the feasibility and efficacy of instituting a hospital-wide program for identifying carriers and attempting to eradicate the infection prior to elective orthopaedic operations.
It is commendable that a hospital of the size of the New England Baptist Hospital has managed to institute such a program, which has been shown here to be successful. We all struggle with trying to institute cost-effective programs that require upfront costs when one part of the hospital budget may not benefit directly from cost savings in another part of the hospital budget. Regardless, this program was shown to be highly effective. During the study period, just over 7000 patients underwent screening for both methicillin-resistant Staphylococcus aureus and methicillin-sensitive Staphylococcus aureus, with a remarkable screening rate of 95.7%. During the study period, the surgical site infection rate was 0.19%. There were three methicillin-resistant Staphylococcus aureus infections and three methicillin-sensitive Staphylococcus aureus infections in carriers. In addition, there was one methicillin-resistant Staphylococcus aureus infection and six methicillin-sensitive Staphylococcus aureus infections in noncarriers. Screening revealed that 22.6% of patients were methicillin-sensitive Staphylococcus aureus carriers and 4.4% were methicillin-resistant Staphylococcus aureus carriers. The rate of operative site infection among methicillin-resistant Staphylococcus aureus carriers (0.97%) was significantly different from the rate in noncarriers (0.14%). The rate of surgical site infection among methicillin-sensitive Staphylococcus aureus carriers (0.19%) was not significantly different from the rate in noncarriers (0.14%).
The authors also evaluated a control time period prior to the institution of their program. The rate of surgical site infection in this prior time period was 0.45% overall, compared with 0.19% once the screening program began; this reduction in the infection rate was highly significant. The reduction in infection rate was relatively greater for methicillin-resistant Staphylococcus aureus-associated surgical site infections than for methicillin-sensitive Staphylococcus aureus-associated infections.
Of the 309 methicillin-resistant Staphylococcus aureus carriers, 85% successfully completed all components of the eradication protocol and were subsequently retested, at which time 78% of these carriers had negative results and 22% were found to be persistently colonized. During the study period, only one of 5122 patients developed methicillin-resistant Staphylococcus aureus-related infection following eradication of the methicillin-resistant Staphylococcus aureus carrier status.
This paper highlights the importance of a screening program for methicillin-resistant Staphylococcus aureus carrier status. Unfortunately, the authors did not carry out a cost-benefit analysis but the reduction in the infection rate is impressive. Considering the cost of treating postoperative infection, a cost-benefit analysis may be expected to show that this screening is cost-effective.
The other paper, by Schwarzkopf and associates, assessed the prevalence of methicillin-resistant Staphylococcus aureus and methicillin-sensitive Staphylococcus aureus in the nares of physicians at the Hospital for Joint Diseases in New York.
Of the seventy-four surgeons and sixty-one residents screened for methicillin-resistant Staphylococcus aureus and methicillin-sensitive Staphylococcus aureus, the total carrier status was 1.5% for methicillin-resistant Staphylococcus aureus and 35.7% for methicillin-sensitive Staphylococcus aureus. For residents this rate was 0% for methicillin-resistant Staphylococcus aureus and 59% for methicillin-sensitive Staphylococcus aureus, and for surgeons the rate was 2.7% for methicillin-resistant Staphylococcus aureus and 23.3% for methicillin-sensitive Staphylococcus aureus.
It has been shown in previous studies5 that 3% of methicillin-resistant Staphylococcus aureus outbreaks are caused by asymptomatic colonized health-care workers. Schwarzkopf et al. also evaluated a control group of patients, in whom the prevalences of nasal methicillin-resistant and methicillin-sensitive Staphylococcus aureus were 2.17% and 35.7%, respectively.
Schwarzkopf et al. found no correlation between the history of antibiotic use in the previous month or recollection of having treated a methicillin-resistant Staphylococcus aureus-positive surgical site infection and carrier status in surgeons. There was a significant negative correlation between the number of hospitals at which the residents worked and methicillin-sensitive Staphylococcus aureus colonization rates in residents, as residents who worked at more hospitals tended to have a lower rate of methicillin-sensitive Staphylococcus aureus colonization.
As this paper shows a relatively high prevalence of carrier status of methicillin-resistant Staphylococcus aureus and methicillin-sensitive Staphylococcus aureus in surgeons and residents, one can conclude that it is extremely important for health-care workers to practice appropriate precautionary measures to minimize the risk of surgical site infection. Proper hand hygiene is probably the most important measure that can be used by health-care professionals, and this certainly applies to residents, physicians, and orthopaedic surgeons. This paper will serve as a reminder to all of us about the importance of hand hygiene and as a reminder not to underestimate the role of health-care professionals in the transmission of bacteria to surgical sites.
Both sets of authors need to be congratulated for their excellent work, which helps us with the practical day-to-day aspects of orthopaedic care as we strive to improve the outcomes for our patients.