Antibiotic Prophylaxis for Aortic Surgery

Primary Recommendation

The American Society of Anaesthesiologists recommends cefazolin 2g IV as the first-line antibiotic prophylaxis for aortic surgery, administered as a slow infusion within 60 minutes before incision, with redosing of 1g if the procedure exceeds 4 hours, limited to the operative period (maximum 24 hours) 1, 2
Cefazolin is the standard of care for aortic surgery prophylaxis, targeting the most common pathogens: Staphylococcus aureus, S. epidermidis, and gram-negative bacilli 1, 2
The initial dose is 2g IV slow infusion, with redosing of 1g if surgery duration exceeds 4 hours 1, 2
Prophylaxis should be limited strictly to the operative period, with a maximum duration of 24 hours postoperatively 1, 2

Vancomycin 30 mg/kg over 120 minutes should be reserved for specific high-risk scenarios, such as documented beta-lactam allergy, known or suspected MRSA colonization, reoperation in a patient hospitalized in a unit with MRSA ecology, or recent antibiotic therapy 1, 2, 3
Vancomycin is less effective than cefazolin against methicillin-susceptible S. aureus and streptococci 3

The 120-minute infusion of vancomycin must be completed at the latest by the beginning of the intervention, ideally 30 minutes before incision 1, 2
Cefazolin requires redosing every 4 hours intraoperatively 1, 2

The 2019 guideline from the American Society of Anaesthesiologists provides the highest quality evidence for aortic surgery prophylaxis 1, 2
Aortic surgery is classified as clean surgery (Altemeier class 1), but the use of prosthetic grafts significantly increases infection risk 2
The effectiveness of antibiotic prophylaxis has been clearly demonstrated in vascular surgery with prosthetic material 2

Never extend prophylaxis beyond 24 hours postoperatively, as this increases antibiotic resistance risk without improving outcomes 1, 2, 3
Do not use vancomycin routinely when cefazolin is appropriate, as vancomycin is inferior for methicillin-susceptible organisms 3
Ensure proper timing: antibiotics must be infused within 60 minutes of incision (120 minutes for vancomycin) to achieve adequate tissue concentrations 3
Do not skip redosing during prolonged procedures—cefazolin requires redosing every 4 hours intraoperatively 1, 2