Remote infections at the time of surgery, such as urinary tract infection or pneumonia, significantly raise the risk of SSI (EVIDENCE CATEGORY IA).
Strongly consider canceling elective surgery if there is an untreated remote infection, especially if implanting bioprosthetic material.
Careful technique reduces risk of infection.
Breaks in sterile technique and gross spillage of enteric contents raise the risk for SSI through increased bacterial load.
Poor hemostasis, excess tissue trauma, inadequate debridement or dead space obliteration, and inappropriate suture technique raise the volume of unperfused biological matter (EVIDENCE CATEGORY IB).
Timely completion of the operation also minimizes risk. Prolonged operative time can heighten the risk of breaches in sterile technique. Recommendations call for procedures to be completed within the 75th percentile of standardized operative times.
The principles for using preoperative antibiotics include maximal subcutaneous concentration when making the incision (TABLE 2) (EVIDENCE CATEGORY IA). This corresponds with intravenous antimicrobial administration within 60 minutes before incision (or within 120 minutes for vancomycin or fluoroquinolones). An additional dose of the antimicrobial agent is indicated if the procedure time exceeds 2 half-lives of the agent.
Institutional policies for antibiotic restriction aimed at curtailing resistant organisms do not appear to change the spectrum of causative microbes in SSI.22 Short-duration therapy preserves antimicrobial efficacy best, so avoid the routine use of agents such as vancomycin (EVIDENCE CATEGORY IB).
Short duration also applies when antimicrobial prophylaxis is indicated. The CDC recommends extending antimicrobial prophylaxis no more than a few hours after incision closure (EVIDENCE CATEGORY IA). Particular cases may require longer antimicrobial prophylaxis, but prophylaxis beyond 24 hours does not reduce SSI rates and increases the potential for microbial resistance.
While a single dose of broad-spectrum antibiotic may cause Clostridium difficile colitis, prolonged duration also raises risk through profound changes in gut flora that favor the emergence of this opportunistic pathogen.
Category IA. Strongly recommended for all hospitals and strongly supported by well-designed experimental or epidemiologic studies.
Category IB. Strongly recommended for all hospitals and viewed as effective by experts in the field and a consensus of Hospital Infection Control Practices Advisory Committee (HICPAC), based on strong rationale and suggestive evidence, even though definitive scientific studies may not have been done.
Category II. Suggested for implementation in many hospitals. Recommendations may be supported by suggestive clinical or epidemiologic studies, a strong theoretical rationale, or definitive studies applicable to some, but not all, hospitals.
No recommendation; unresolved issue (NR). Insufficient evidence or no consensus regarding efficacy.
Principles of antimicrobial prophylaxis
|Consider these factors:|
|Risk for developing surgical site infection.|
|Potential severity of consequences|
|Cardiothoracic or vascular surgery|
|Agents must be safe, inexpensive, and bactericidal|
|Appropriate spectrum based on anticipated flora of involved tissues and spaces|
|Administer so that maximal effect is at time of incision, and re-administer when appropriate|
|Alter dosage as appropriate for the patient (eg, obesity)|
This article is adapted from DiRocco JD, Pavone LA, Weiss CA III. The evidence-based way to prevent SSI. Contemp Surg. 2005;61:120–127.