Antibiotic Management for Gunshot Wounds

Classification and Initial Approach

The American Academy of Orthopaedic Surgeons recommends classifying gunshot wounds as a type of open fracture, with antibiotic selection depending on the velocity of the missile and the degree of contamination 1, 2
Low-velocity wounds have less tissue damage, but the need for antibiotics is controversial, while high-velocity wounds have extensive tissue damage and require definitive antibiotic therapy 2, 3, 4
The degree of contamination is also a factor, with clean wounds having minimal contamination 1, and contaminated wounds having soil, clothing, or foreign material present 5

The American Academy of Orthopaedic Surgeons recommends first-generation cephalosporin (e.g., cefazolin) as first-line therapy for gunshot wounds 1, 2
For more severe injuries, a combination of first-generation cephalosporin and aminoglycoside is recommended 2, 5
For gross contamination or soil exposure, adding penicillin for anaerobic coverage, particularly Clostridium species, is recommended 1, 6

The American Academy of Orthopaedic Surgeons recommends 24-48 hours of antibiotic therapy for low-velocity wounds, and 48-72 hours for high-velocity wounds 1, 4, 6, 7
For open fractures associated with gunshot wounds, the recommended duration of therapy is 3 days for Grade I and II fractures, and up to 5 days for Grade III fractures 2, 5

The American Academy of Orthopaedic Surgeons recommends starting antibiotics as soon as possible, as delay beyond 3 hours significantly increases infection risk 3, 5
For human bite-related gunshot wounds, consideration should be given to using amoxicillin-clavulanate, ampicillin-sulbactam, or ertapenem for coverage of oral flora including Eikenella corrodens 8
Inadequate coverage, such as failure to cover anaerobes in contaminated wounds, can lead to serious infections including gas gangrene 1, 6

The initial dose is 2 grams IV administered slowly, ideally 30-60 minutes before the start of surgery to ensure adequate tissue levels 9
If surgery lasts more than 4 hours, 1 gram of cefazoline should be re-administered to maintain therapeutic concentrations throughout the procedure 9, 10
For thoracic procedures with lung resection, European guidelines specify the same dose of 2 grams with re-dosing if the duration exceeds 2 hours 10

The treatment should be strictly limited to the operative period, with an absolute maximum of 48 hours in exceptional cases 9
Never extend antibiotic prophylaxis beyond 48 hours, as this increases the risk of bacterial resistance without clinical benefit 9

For rib fractures with prosthetic material or implants, the same dose of 2 grams is maintained, with re-dosing of 1 gram if the duration exceeds 4 hours 9, 10

In cases of severe contamination or soil exposure, penicillin should be added for anaerobic coverage, particularly against Clostridium species is not applicable due to [ignore ref], however, an alternative is: If there is an allergy to beta-lactams, the alternative is vancomycin 30 mg/kg administered over 120 minutes 9, 10
In more severe injuries or with significant contamination, consider adding an aminoglycoside (gentamicin 5 mg/kg/day) for gram-negative coverage 10