Appropriately selected and timely prophylactic antimicrobial agents are proven to decrease SSI rates in breast cancer patients undergoing surgical treatment [22
]. Surgeons may hesitate to follow this recommendation because uncontrolled and injudicious use of PAs may lead to antibiotic resistance [25
], adverse effects (e.g.: Clostridium difficile
], and increase medical costs [27
] because they decrease SSI symptoms until after the patient has been discharged [28
]. Nevertheless, the benefits related to this measure outweigh the sporadic number of complications.
Our study shows that the majority of breast surgeons that responded to this survey use some type of PA in breast cancer patients before surgery whether it is administered routinely in all patients or selectively when dealing with specific high-risk variables associated with SSI. Nonetheless, among those surgeons that reported using PAs the practice pattern is heterogeneous. In the literature there is evidence that this disparity is also common amongst surgeons from other countries. For example, a British survey reported that up to 33% of surgeons who performed wide local excisions, mastectomies and sentinel lymph node biopsy used PAs [29
]. Another study carried out in Spain reported that 52% of hospitals used PAs in breast surgery [30
] although a more recent multi-centric Spanish study revealed that the rate of use of PAs was much higher (97.81%) [31
]. These results must be analyzed cautiously because breast cancer surgeries are not always carried out by breast surgeons or other sub-specialized surgeons so there may be a bias in the way the information is gathered.
Studies have evaluated the impact of PAs, but have showed mixed results. Two studies reported a reduction in SSI rates that ranged from 33 to 88% after using cefotaxime and azithromycin [1
]. Other researchers have not found any significant reduction in SSI rates [23
]. Nonetheless, a Cochrane review concluded that using pre-operative antibiotics significantly reduces the risk of SSI (pooled risk ratio 0.71, 95% confidence interval 0.53-0.94) in patients undergoing surgery for breast cancer when compared with placebo or no treatment [7
]. This type of prophylactic intervention is reported to potentially benefit high-risk patients especially when they have any of the following risk factors: neoadjuvant chemotherapy, immediate breast reconstruction, blood transfusion, obesity, and smoking [24
In our study 80% of surgeons reported that they used PAs in patients undergoing breast reconstruction. In a survey of the members of the American Society of Plastic Surgeons the use of PAs was slightly higher (>90%) [33
]. The authors stated that plastic surgeons use PAs in patients undergoing any type of cosmetic or reconstructive breast surgery because a higher rate of SSI would exist if they were not used and also because these types of surgeries per se
increase the risk of SSI as they have a longer length of duration and use foreign bodies (e.g.: implants). This concept certainly goes along with the recommendation made by the Hospital Infection Control Practices Advisory Committee of the U.S. Centers for Disease Control and Prevention in which clean procedures require antibiotic prophylaxis when implanting foreign material and in any case where an SSI may pose a catastrophic risk [34
In addition to the standard SSI risk factors inherent to any patient (e.g.: obesity, history of smoking, diabetes, etc.) [34
], breast cancer surgery patients have additional, specific risk factors (e.g.: neoadjuvant chemotherapy, re-operations, use of foreign bodies such as implants and drains in situ
, and post-operative seroma) [14
] that increase their susceptibility to post-operative infections. As a result of this, breast cancer patients exceed the 1.5% SSI rate suggested for elective clean surgery [35
]. Accordingly, at least 40% of the breast surgeons within our study reported that they administered PAs specifically when their patients had any of these SSI risk factors.
The details of drug choices amongst surveyed surgeons are in line with current recommendations. PAs are typically directed against gram-positive bacteria that comprise normal skin flora (staphylococci and streptococci). Ng et al.
reported that British surgeons tend to use amoxicillin-clavulonic acid more often than cephalosporins [29
]; however at many institutions cefazolin is preferred. For example, Codina et al.
reported that the majority (36%) of hospitals in Spain prefer cefazolin [30
]. Studies evaluating the effectiveness of cephalosporins to reduce breast surgery SSI have had mixed results [20
]. In the past, most breast surgery SSIs were caused by staphylococci and streptococci [5
], but recent data suggests that there are significant rates (30–66.2%) of non-staphylococcal infections [35
]. Additionally, 63% of the staphylococcal isolates have been documented to be resistant to at least one antibiotic [39
]. Breast surgeons should be aware of this fact and monitor patients with complicated wounds that do not respond to standardized treatments. In the future there may be a need to change the PAs we are currently using.
Our survey brings to light a couple of issues regarding standardized prescription practices that require improvement in the clinical practice of breast surgeons in Colombia. In this survey only 2.1% of the breast surgeons answered that they actually weight-adjust their preoperative dosing. Although cefazolin is an antibiotic with prolonged half-life, its ability to prevent SSI is significantly affected by sub-optimal dosing therefore in order to assure optimal drug concentrations appropriate weight adjusted dosing and re-dosing is mandatory. On another note, the self-reported timeliness of antibiotic administration is compliant with current recommendations [40
] in 89.4% of the breast surgeons we surveyed. Despite the fact that the majority of breast surgeons in this cohort understand the essential role of when and how long PAs should be administered to actually prevent SSIs, there are a significant number of surgeons that reported they extended the use of PAs beyond the first 24 hours post-surgery exclusively with the intention to reduce the risk of SSI. A similar practice pattern has been reported in Spain in which 9% of surveyed hospitals self-reported that their surgeons prolonged the use of PAs for over 24 hours when performing breast surgeries [30
]. Randomized studies have shown that administering PAs for only 24 hours is enough to prevent SSIs and that prolonging its use does not provide any additional benefit [41
], but instead increases the risk of generating resistant bacterial strains [42
], nosocomial infection [42
], diarrhea [26
], higher health-care costs [27
], and increased work load for health-care staff [43