Surgical site infections (SSIs) are major concerns for all surgical specialties, with the literature reporting SSI risks of 2–4% for “clean surgery” [1]. Higher rates have been reported for post-traumatic procedures (15–50%), or in selected populations, including high-risk vascular surgery patients (15–22%), and accompanied by a considerable lengthening of hospitalization times, a high mortality rate (26–67%), and the cost-burden to community [2,3]. Similarly, SSI-mediated morbidity may be higher when prosthetic grafts are used in complex surgeries; thus, SSI prevention and treatment are both clinically significant. The current recommendations for clean vascular surgical procedures advocate no more than 24 h of intravenous antibiotic post-operative therapy, as no benefits are indicated past this treatment period [4,5,6]. However, when overt infection signs or risks are present, in particular, when synthetic prostheses are concerned, the literature is less clear on this topic. Therefore, as these indications require clarification, interest continues to be strong in the use of new antibiotics and also in alternative methods of their delivery.

In vascular surgery, lower extremity bypass surgery for limb salvage has the highest rate of SSI incidence, with rates varying between 5% and 30% [1,2,3,4,5,6]. SSIs increase hospital stays, increase readmission rates, incur elevated mortality and morbidity rates, increase healthcare burdens, and increase the incidence of repeat revascularization surgeries [4,5]. Moreover, several health risk factors such as diabetes, smoking, being female, prosthetic grafts, obesity, and steroid use contribute to lower extremity SSIs [7,8,9,10,11].

While some risk factors are not modifiable, identifying modifiable factors can successfully reduce SSIs. In particular, the rapid identification of causative bacteria is vital to establish and select the most appropriate antibiotic therapy. While any bacteria can theoretically infect a vascular prosthesis or contribute to an SSI, the Gram-negative Pseudomonas aeruginosa and Gram-positive Staphylococcus epidermidis and Staphylococcus aureus strains are the most commonly found in SSIs of the groin, while fungal infections are found less frequently, although present in the inguinal area [8,12,13,14,15]. A considerable challenge to SSI diagnostics and treatment are biofilms (or microfouling) [16,17]: these complex bacterial polymeric aggregations, consisting of bacterial glycocalyx with incorporated microcolonies, are characterized by the secretion of protective matrix adhesives that provide safe environments from external antimicrobial agents and host defenses [16]. Biofilms become manifest as polymicrobial infections and contain dominant, highly resistant, difficult-to-eradicate bacteria, which increase patient mortality and morbidity [18].

As in all surgical specialties, vascular SSI bacterial typology has changed over time, and is reflected by an elevated incidence of antibiotic-resistant bacteria, especially Staphylococcal family members. In particular, methicillin-resistant S. aureus (MRSA) infections are a serious risk factor for nosocomial-morbidity and morbidity in terms of admission to intensive care, repeated surgical procedures, and major amputation infection risks [19,20,21,22]. Rarely, isolated strains of Staphylococcus aureus are still sensitive to penicillin. More frequently, these Staphylococci are distinguished as MRSA (methicillin-resistant Staphylococcus aureus) and MSSA (methicillin-sensitive Staphylococcus aureus). Resistance to penicillin (MSSA) is conferred by a bacterial penicillinase. This resistance can be overcome by adding a beta-lactamase inhibitor (e.g., amoxicillin/clavulanic acid, ampicillin/sulbactam) or by using a penicillinase-resistant penicillin (e.g., oxacillin). Methicillin resistance (MRSA) is conferred by the presence of the bacterial gene mecA, which codes for a penicillin-binding protein, an enzyme that has a low affinity for beta-lactams, and therefore leads to resistance to methicillin and oxacillin. There are MRSA of hospital origin often characterized by extended resistance to antibiotics (MDR, multidrug resistance) and MRSA that is community-acquired, CA-MRSA; the latter of which can maintain sensitivity to tetracyclines (tetracycline, doxycycline, minocycline, tigecycline) [23].

In recent years, the WHO Report on Surveillance of Antibiotic Consumption (2016–2018) described how the percentage of MRSA, in the evaluation of hospital infections, has remained stable (around 34%). Relative to Gram-positive bacteria, the highest resistance rates were observed for S. aureus to erythromycin (38.9%), clindamycin (34.4%), methicillin (33.5%), and levofloxacin (31.5%). For many years, the treatment of choice to combat MRSA has been based on the use of glycopeptides (vancomycin and teicoplanin); however, the excessive and careless use of these antibiotics has led to the emergence of strains with decreased sensitivity to vancomycin. In recent years, new antibiotics have been introduced into clinical practice, such as linezolid, daptomycin, and more recently, ceftaroline, also in combination with vancomycin and daptomycin, for the treatment of severe MRSA infections. For the latter antibiotics too, particularly linezolid and daptomycin, the emergence of resistant strains has been observed [24]. Thus, active SSI prevention is highly advisable for peri-operative antibiotic therapy, in addition to the usual stringent antiseptic and sterility policies. Such combinations should minimize vascular SSI onset, especially in inguinal areas.

Although SSIs are relatively rare in vascular surgery, they have serious effects. Thus, pre-operative infection prophylaxes are advised to minimize infection risks, especially for patients with synthetic grafts. To address this, we analyzed the evidence on pre-operative antibiotics prior to vascular surgery. Firstly, for most vascular interventions, Gram-positive bacteria, in particular S. aureus, represent approximately 80% of all SSIs [2,3]. In contrast, Gram-negative bacteria are implicated in 20% to 25% of infections [1,2,3,4]; however, for effective antibiotic prophylaxis, both bacterial types should be targeted and controlled.

Synthetic vascular prosthesis implantation generates particular microenvironments and conditions that can promote bacterial wound invasion and biofilm formation; this latter functionality defends enclosed bacteria from antibiotic therapy and host defense [38]. To reduce or eliminate the bacterial colonization of damaged tissues, an antibiotic prophylaxis should be administered for effective drug concentrations in tissue at the surgical site before surgery commences. Therefore, the administration of pre-operative antibiotic therapy is advisable 60 min before surgery, and also in additional intraoperative doses if the operation lasts more than 4 h and/or more than 1500 cc blood is lost [25,38].