Pre-operative skin preparation practices: results of the 2007 French national assessment

Skin preparation before hip replacement in emergency setting versus elective scheduled arthroplasty: bacteriological comparative analysis

INTRODUCTION

Hip arthroplasty needs to be performed in an emergency setting after intracapsular femur neck fracture, whereas pain makes preoperative skin preparation of the limb difficult and it may therefore be incomplete. To date no study has analyzed the patient's skin bacteriological status in these surgical conditions.

HYPOTHESIS

The skin's bacterial flora is quantitatively and qualitatively different in the trauma context compared to an elective scheduled arthroplasty for chronic hip disease.

MATERIALS AND METHODS

Two groups of patients, undergoing hip arthroplasty and having the same preparation at the time of surgery but different skin preparation procedures the day before and the day of surgery, were prospectively compared: 30 patients operated on in an emergency setting for fracture (group A) had no skin preparation and 32 patients operated on in scheduled surgery (group B). Group A had no skin disinfection before going into surgery, whereas group B followed a predefined protocol the day before surgery. Skin samples were taken on gelose at three different stages of skin preparation at the time of surgery (before and after detersive cleaning, and at the end of the surgery) and on two sites (inguinal and greater trochanter). The bacteriological analysis took place after 48 hours of incubation.

RESULTS

Before detersive cleaning, group A had 3.6 times more bacteria than group B in the trochanter region and 2.7 times more in the inguinal area. After detersive cleaning, the contamination rate in the trochanter area was similar in both groups (group A: 10%; group B: 12.5%), but different in the inguinal region (group A: 33%; group B: 3%; P=0.002). At the end of the surgery, no difference was identified. Coagulase-negative Staphylococcus and Bacillus cereus accounted for 44% and 37%, respectively, of the bacteria isolated. In addition, the frequency of pathogenic non-saprotrophic bacteria was higher in group A (38%) compared to group B (6%). At a mean follow-up of 9.7 months (range: 8-11 months), no infection of the surgical site was identified.

CONCLUSION

The dermal flora is more abundant and different when the patient is managed in an emergency context. Although effective in the trochanter area, cutaneous detersive cleaning in the operating room is insufficient in the inguinal area and the frequency of pathogenic bacteria warrants identical rigor in preoperative preparation in all situations.

LEVEL OF EVIDENCE

III. Prospective case - control study.

Enterobacteriaceae surgical site infection after cardiac surgery: the hypothetical role of vancomycin

BACKGROUND

In the middle of October 2011, the Hygiene Department of Caen University Hospital suspected an outbreak of surgical site infections (SSI) after open-heart operations with an unusually high proportion of microorganisms belonging to the Enterobacteriaceae family. The attack rate was 3.8%, significantly different (p = 0.035) from the attack rate of 1.2% in 2010 over the equivalent period. A case-control study was conducted to search specifically for risk factors for Enterobacteriaceae infections after median sternotomy in cardiac patients.

METHODS

Case patients were defined retrospectively as patients with superficial or deep surgical site infection with Enterobacteriaceae within 30 days of median sternotomy. Four control patients were selected per case patient from patients matched for date of operation (± 15 days) and European System for Cardiac Operative Risk Evaluation (<5, [5-10], >10).

RESULTS

Univariate analysis identified the following risk factors: inappropriate skin preparation on the morning of the intervention (p = 0.046), use of vancomycin (p = 0.030), and number of sternotomy dressings (p = 0.033). A multivariate logistic regression analysis found that vancomycin use was independently associated with an increased risk of postoperative SSI with Enterobacteriaceae (p = 0.019; odds ratio = 7.4).

CONCLUSIONS

Although vancomycin is known to be effective for preventing infection with methicillin-sensitive organisms, our results suggest that it was associated with a risk for the development of SSI with gram-negative organisms after median sternotomy. This study led to a multidisciplinary meeting that defined new guidelines for prophylactic antibiotic therapy before open-heart operations.