Antimicrobial Prophylaxis in Surgery
- Prophylaxis refers to the prevention of an infection and can be characterized as primary prophylaxis, secondary prophylaxis, or eradication. These guidelines focus on primary perioperative prophylaxis — the prevention of an initial infection.
- Prophylaxis is recommended in some cases due to the severity of complications of postoperative infection (eg, an infected device that is not easily removable) necessitating precautionary measures even if infection is unlikely.
- Patient-related factors associated with an increased risk of surgical site infection (SSI) include extremes of age, nutritional status, obesity, diabetes mellitus, tobacco use, coexistent remote body site infections, altered immune response, corticosteroid therapy, recent surgical procedure, length of preoperative hospitalization, and colonization with microorganisms.
- Antimicrobial prophylaxis may be justified for any procedure if the patient has an underlying medical condition associated with a high risk of SSI or if the patient is immunocompromised (eg, malnourished, neutropenic, receiving immunosuppressive agents).
- Although antimicrobial prophylaxis plays an important role in reducing the rate of SSIs, other factors may have a strong impact on SSI rates. These include:
- Attention to basic infection control strategies
- The surgeon's experience and technique
- Duration of procedure
- Hospital and operating room environments
- Instrument sterilization
- Preoperative preparation (eg, surgical scrub, skin antisepsis, and appropriate hair removal)
- Perioperative management (temperature and glycemic control)
- The underlying medical condition of the patient
National Healthcare Safety Network (NHSN) Wound Classification Criteria
- Clean: An uninfected operative wound in which no inflammation is encountered and the respiratory, alimentary, genital, or uninfected urinary tracts are not entered.
- In addition, clean wounds are closed primarily and, if necessary, drained with closed drainage.
- Operative incisional wounds that follow nonpenetrating (blunt) trauma should be included in this category if they meet the criteria.
- Clean-contaminated: Operative wounds in which the respiratory, alimentary, genital, or urinary tracts are entered under controlled conditions and without unusual contamination.
- Specifically, operations involving the biliary tract, appendix, vagina, and oropharynx are included in this category, provided no evidence of infection or major break in technique is encountered.
- Contaminated: Open, fresh, accidental wounds.
- In addition, operations with major breaks in sterile technique (eg, open cardiac massage) or gross spillage from the gastrointestinal tract, and
- Incisions in which acute, nonpurulent inflammation is encountered are included in this category.
- Dirty or infected: Includes old traumatic wounds with retained devitalized tissue and those that involve existing clinical infection or perforated viscera.
Note: This definition suggests that the organisms causing postoperative infection were present in the operative field before the operation.
NHSN Criteria for Defining a Surgical Site Infection
- Superficial incisional SSI: occurs within 30 days postoperatively and involves the skin or subcutaneous tissue of the incision and at least one of the following:
- Purulent drainage from the superficial incision.
- Organisms isolated from an aseptically obtained culture of fluid or tissue from the superficial incision.
- At least one of the following signs or symptoms of infection: pain or tenderness, localized swelling, redness, or heat, and the superficial incision is deliberately opened by a surgeon and is culture-positive or not cultured. A culture-negative finding does not meet this criterion.
- Diagnosis of superficial incisional SSI by the surgeon or attending physician.
- Deep incisional SSI: occurs within 30 or 90 daysa after the operative procedure if no implant is left in place or within 1 year if implant is in place and the infection appears to be related to the operative procedure, involves deep soft tissues (eg, fascial and muscle layers) of the incision, and the patient has at least one of the following:
- Purulent drainage from the deep incision but not from the organ/space component of the surgical site.
- A deep incision spontaneously dehisces or is deliberately opened by a surgeon and is culture-positive or not cultured and the patient has at least one of the following signs or symptoms: fever (>38°C), localized pain or tenderness. A culture-negative finding does not meet this criterion.
- An abscess or other evidence of infection involving the deep incision is found on direct examination, during reoperation, or by histopathologic or radiologic examination.
- Diagnosis of a deep incisional SSI by a surgeon or attending physician.
- Organ/space SSI: involves any part of the body—excluding the skin incision, fascia, or muscle layers—that is opened or manipulated during the operative procedure. Specific sites are assigned to organ/space SSI to further identify the location of the infection (eg, endocarditis, endometritis, mediastinitis, vaginal cuff, and osteomyelitis). Organ/space SSI must meet the following criteria:
- Infection occurs within 30 or 90 daysa after the operative procedure if no implant is in place or within 1 year if implant is in place and the infection appears to be related to the operative procedure,
- Infection involves any part of the body, excluding the skin incision, fascia, or muscle layers, that is opened or manipulated during the operative procedure, and
- The patient has at least one of the following:
- Purulent drainage from a drain that is placed through a stab wound into the organ/space.
- Organisms isolated from an aseptically obtained culture of fluid or tissue in the organ/space.
- An abscess or other evidence of infection involving the organ/space that is found on direct examination, during reoperation, or by histopathologic or radiologic examination.
- Diagnosis of an organ/space SSI by a surgeon or attending physician.
Table 1. Surveillance Period for Deep Incisional or Organ/Space SSI Following Selected NHSN Operative Procedure Categoriesa
|30-day Surveillance||Abdominal aortic aneurysm||Heart transplant||Rectum|
|Abdominal hysterectomy||Kidney||Shunt for dialysis|
|Appendix||Kidney transplant||Small bowel|
|Bile duct, liver or pancreas||Laminectomy||Spleen|
|Carotid endarterectomy||Limb amputation||Stomach|
|Cesarean section||Neck||Thyroid and/or parathyroid|
|Exploratory Laparotomy||Ovary||Vaginal hysterectomy|
|Other operative procedures not included in the NHSN categories|
|90-day Surveillance||Breast||Hip prosthesis||Peripheral vascular bypass|
|Craniotomy||Knee prosthesis||Refusion of spine|
|Heart||Open reduction of fracture||Spinal fusion|
|Coronary artery bypass graft with both chest and donor site incisions|
|Coronary artery bypass graft with chest incision only|
...ble 2. Specific Sites of an Organ/Space SS...
...ial prophylaxis may be beneficial in...
...eight-Based Dosing In theory, using...
...ation of Prophylaxis If an agent...
...ediatrics In most cases, the data in pediatr...
...atients with Prosthetic Implants...
...ization S. aureus (MSSA or MRSA) colonizes a...
...ibiotic Treatment If the agent(s) use...
Table 3. Recommended Doses and Redosing Inter...
...e 4. Antimicrobial Recommendations fo...