What is the recommended pre-operative antibiotic (ABx) prophylaxis for clean surgeries?

Pre-Operative Antibiotic Prophylaxis for Clean Surgeries

For clean surgeries, antibiotic prophylaxis is generally not recommended unless specific risk factors or implantation of prosthetic material is involved. 1

Definition and Classification

Clean surgeries (Altemeier Class 1) are defined as:

• Non-traumatic
• No inflammation encountered
• No break in technique
• Respiratory, gastrointestinal, and genitourinary tracts not entered

When to Use Prophylaxis in Clean Surgeries

Antibiotic prophylaxis is indicated for clean surgeries in the following scenarios:

1. Implantation of prosthetic material:

   • Joint prostheses (upper/lower limb)
   • Foreign material (resorbable or not, cement, bone graft)
   • Spine surgery with prosthetic material
   • Vascular grafts
   • Breast reconstruction/mammoplasty with implants

2. High-risk procedures:

   • Cardiac surgery
   • Neurosurgery with craniotomy or CSF shunt valve placement
   • Clean surgeries in patients with specific risk factors

Recommended Antibiotics for Clean Surgeries

First-line agent:

• Cefazolin: 2g IV slow infusion (30-60 minutes before incision) 1, 2
  • For procedures >4 hours: Re-dose with 1g
  • For obese patients: Consider 3g dose (though evidence for weight-based dosing is debated) 3

For beta-lactam allergic patients:

• Clindamycin: 900 mg IV slow infusion 1
  • Re-dose with 600 mg if procedure >4 hours
  • OR
• Vancomycin: 30 mg/kg IV over 120 minutes 1
  • Infusion should end just before incision, ideally 30 minutes prior
  • Maximum dose: 4g

Specific Recommendations by Surgery Type

Orthopedic Surgery

• Joint prosthesis: Cefazolin 2g IV (re-dose if >4 hours)
• Arthroscopy without implant: No prophylaxis needed
• Extra-articular soft tissue surgery without implant: No prophylaxis needed
• Spine surgery with implant: Cefazolin 2g IV (single dose)

Cardiac Surgery

• All procedures: Cefazolin 2g IV

Breast Surgery

• Simple lumpectomy: No prophylaxis needed
• Mastectomy/reconstruction with implant: Cefazolin 2g IV

Neurosurgery

• Craniotomy: Cefazolin 2g IV
• CSF shunt valve placement: Cefazolin 2g IV

Critical Timing of Administration

Timing is crucial for efficacy:

• Administer 30-60 minutes before surgical incision 4, 5
• For vancomycin: Begin infusion 120 minutes before incision to complete by incision time
• Re-dosing intervals should be based on the half-life of the antibiotic
• Postoperative administration beyond 24 hours is generally not recommended 1, 6

Common Pitfalls to Avoid

1. Inappropriate timing: Administering antibiotics too early (>2 hours before incision) or after incision significantly increases infection risk 4

2. Unnecessary prophylaxis: Using antibiotics for all clean procedures without risk factors or prosthetic material increases antibiotic resistance and costs

3. Extended duration: Continuing antibiotics beyond the recommended period (usually limited to the operative period, maximum 24 hours) provides no additional benefit and increases risks

4. Inappropriate dosing in obese patients: While higher doses are often used, the evidence for weight-based dosing is controversial as cefazolin is hydrophilic and doesn't penetrate adipose tissue well 3

5. Neglecting re-dosing: Failing to re-dose for prolonged procedures when the duration exceeds 1-2 half-lives of the antibiotic

By following these evidence-based guidelines for antibiotic prophylaxis in clean surgeries, surgical site infections can be minimized while avoiding unnecessary antibiotic use.