Why is Ceftriaxone (a cephalosporin antibiotic) 1g given prior to surgery in the Operating Room (OR)?

Why Ceftriaxone 1g is Given Prior to Surgery

Ceftriaxone 1g is administered preoperatively to prevent surgical site infections (SSIs) by ensuring adequate tissue antibiotic concentrations during the critical period of bacterial contamination at incision and throughout the procedure. 1, 2

Primary Purpose: Surgical Site Infection Prevention

• The goal is to achieve tissue antibiotic levels exceeding the minimum inhibitory concentration (MIC) for likely pathogens from the moment of incision through wound closure. 1
• Prophylactic antibiotics reduce postoperative infection rates dramatically—in the Dutch Trauma Trial, ceftriaxone reduced infection rates from 8.3% to 3.6% (P < 0.001) in closed fractures. 1, 2
• A meta-analysis of 8,307 patients showed single-dose antibiotic prophylaxis significantly reduced both superficial and deep wound infections (relative risk 0.4,95% CI 0.24-0.67). 1

Timing is Critical for Efficacy

• Ceftriaxone must be administered within 60 minutes before surgical incision, ideally 30 minutes prior, to ensure adequate serum and tissue concentrations when contamination occurs. 1, 2
• The antibiotic infusion should be completed before tourniquet inflation in orthopedic cases. 1
• Research confirms that serum and tissue concentrations of 1g ceftriaxone remain significant (>4 mg/L) throughout laparoscopic procedures when given immediately prior to incision. 3, 4

Why Ceftriaxone Specifically

While cefazolin is the preferred first-line agent for most surgical prophylaxis 1, ceftriaxone has specific advantages:

• Ceftriaxone has a prolonged half-life of approximately 15.7 hours, allowing single-dose coverage for extended procedures. 5
• It provides broad-spectrum coverage against both gram-positive (including Staphylococcus aureus) and gram-negative bacteria (Enterobacteriaceae). 1, 6
• The long half-life eliminates the need for intraoperative redosing, reducing nursing effort and costs. 7

However, current guidelines prioritize cefazolin over ceftriaxone for routine prophylaxis because third-generation cephalosporins like ceftriaxone are generally not recommended as first-line agents to preserve their antimicrobial stewardship value. 1, 6

Duration: Single Dose is Sufficient

• Prophylactic antibiotics should be limited to a single preoperative dose for most clean and clean-contaminated procedures. 1, 2
• Continuation beyond 24 hours postoperatively provides no additional benefit and increases antibiotic resistance risk. 1, 2
• For procedures exceeding 2-4 hours (typically two half-lives of the antibiotic) or with significant blood loss (>1.5L), intraoperative redosing may be needed. 1

Target Pathogens

• Prophylaxis targets the most common surgical contaminants: skin commensals (Staphylococcus aureus, coagulase-negative staphylococci) and, for procedures opening mucosa, normal flora including gram-negative organisms. 1
• For colorectal surgery, anaerobic coverage (metronidazole) must be added to cephalosporin prophylaxis. 1

Critical Pitfalls to Avoid

• Delaying administration beyond 60 minutes before incision significantly reduces efficacy. 2
• Extending prophylaxis beyond 24 hours increases resistance without reducing infection rates. 1, 2
• The presence of surgical drains does not justify prolonged prophylaxis. 2
• In neonates, ceftriaxone is contraindicated if calcium-containing IV solutions are needed due to precipitation risk. 8
• Ceftriaxone should not be mixed with calcium-containing diluents like Ringer's solution. 8

Dosing Considerations

• The standard adult dose is 1-2 grams IV, with 1g being adequate for most procedures. 8, 7
• For surgical prophylaxis specifically, the FDA label recommends 1g administered intravenously 0.5 to 2 hours before surgery. 8
• Obese patients (≥120 kg) may require higher doses to ensure adequate tissue concentrations. 1
• Body mass index significantly correlates with tissue concentration at incision time. 3, 4

Cost-Effectiveness

• Single-dose ceftriaxone prophylaxis reduced postoperative infection rates from 11.8% to 1.3% in orthopedic surgery, with dramatic reductions in hospital stay (3.25 vs 7.09 days) and overall costs. 7