Prevention of Surgical Site Infections

Today we had a case of a post-sternotomy sternal wound infection. This led to a discussion on the prevention of surgical site infections (SSI) -- nosocomial, potentially preventable infections that lead to increased morbidity and mortality, cost, and length of stay.

Keys to prevention of SSI (SHEA guidelines here):

• Encourage smoking cessation
  
• Existing infections, distant from the surgical site should ideally be treated first
• Patient should be freshly showered either before the OR or the night before, often using chlorhexadine body wash (conflicting evidence on utility, see review here)
  
• Hair removal, if absolutely required, should be done with clippers
  
• Surgical site antimicrobial prophylaxis (SSP) should be chosen based on the local epidemiology and the type of surgery
• SSP should be administered within 1 hour of the first incision, ideally before the incision. Repeat doses should be administered based on the half life of the agents involved and the length of the case. Total duration should be less than 24 hours
  
• Maximal attention to sterile technique and the donning of sterile gloves, gowns, masks, and hats
• Avoidance of severe (more than 11.0) hyperglycemia peri-operatively
• Avoidance of intraoperative hypothermia (less evidence)
  

The article I was discussing regarding pre-operative chlorhexadine decolonization was actually older than I thought -- 2006 JAMA, available here. NNT was 16 to prevent nosocomial infection. Relatively high quality study.

Pre-operative mupirocin has not been shown to be beneficial for SSI (Canadian study here, larger study here) but may reduce nosocomial staph aureus infections.

No study has rigorously evaluated full pre-operative staph aureus decolonization with this protocol, which is used in Toronto for MRSA. I would probably choose to do this for elective surgeries for patients with known MRSA if there were no contraindications.