Is Antibiotic Prophylaxis in Surgery a Generally Effective Intervention? Testing a Generic Hypothesis Over a Set of Meta-Analyses

Department of Public Health and Epidemiology, School of Medicine, University of Birmingham, Edgbaston, Birmingham, United Kingdom.
Annals of surgery (Impact Factor: 8.33). 05/2009; 249(4):551-6. DOI: 10.1097/SLA.0b013e318199f202
Source: PubMed


While the main focus of a meta-analysis is often to assess the effectiveness of a particular intervention in managing or curing a specific condition, there exists a substantial amount of information within published systematic reviews that could be used to assess the validity of a generic hypothesis about the effectiveness of an intervention across a range of different but related conditions.
To systematically search for and then collate the results of meta-analyses for the effectiveness of antibiotic prophylaxis in preventing postoperative wound infection across various types of surgery in order to assess generic hypotheses about the effectiveness of this intervention in surgery as a whole. With the relative risk of wound infection used as the measure of clinical effectiveness, the hypotheses to be assessed were first that antibiotic prophylaxis would be an effective intervention for preventing wound infection over a broad range of different surgical procedures, and second that there would be a substantial difference in the effectiveness of antibiotic prophylaxis between "clean" and "contaminated" surgical procedures.
Medline and the Cochrane Database of Systematic Reviews.
Eligible meta-analyses were meta-analyses published between 1990 and 2006 of randomized controlled trials that looked at the effectiveness of prophylactic antibiotics versus no antibiotic or placebo in preventing postoperative wound infections.
Independent data extraction by multiple observers.
The first hypothesis was strongly supported by the data as evidenced by the fact that the estimates of the relative risk of infection for the 23 types of surgery that were included in the study were all less than 1. However, there was no real evidence supporting the second hypothesis that the relative risk of wound infection would substantially vary over different levels of surgery cleanliness.
: As well as antibiotic prophylaxis being a generally effective intervention for preventing postoperative wound infection, the level of this effectiveness would appear to be reasonably independent of what type of surgery is being considered. Therefore, the general prevailing attitude that antibiotic prophylaxis should be assumed to be ineffective unless its effectiveness has been experimentally proven beyond doubt for the specific type of surgery being considered, perhaps should be revised. In particular, perhaps a sensible philosophy would be to assume that antibiotic prophylaxis is effective in reducing the risk of wound infection for all types of surgery, even ones where no clinical trial data exists and make exceptions to this rule if, for certain types of surgery, it can be proved to the contrary.

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    • "According to Howe and Boothe (2006), each type of surgical procedure and each body system encountered has its own unique risks and potential pathogens that could result in Surgical Site Infections (SSIs). Therefore, antibiotic usage following surgery for prevention of increased morbidity and expenses associated with surgical infection is a well-accepted part of clinical practice (Holmberg, 1978; Ludwig et al., 1993; Furukawa et al., 2004; Bowater et al., 2009); whereas, the bacterial populations of the control animals in this study were not reduced after partial gastrectomy, while also, there were no recorded postoperative infections in both the experimental animals and the control animals. Moreover, the study of Kang et al. (2009) also reported that there was no significant difference in the incidence of postoperative wound infections between patients who had received postoperative prophylactic antibiotic administration and those who had not. "
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    ABSTRACT: Prolonged post-surgical antibiotic administration may be of less advantage in prevention of post-surgical infections. This study therefore, aimed at investigating the prolonged effect of empiric administration of three most-prescribed antibiotics (amoxicillin, cefotaxime and oxytetracycline) by veterinary practices in Southwest Nigeria on intestinal bacterial population of dogs undergoing partial, non-laparoscopic gastrectomy. Using conventional quantitative and qualitative microbial culture procedures, the total bacterial populations were mostly too numerous to count (TNTC) before gastrectomy but log103-105 cfu/mL after, while control were log 105-107 cfu/mL after gastrectomy. On general-purpose, special, differential and selective culture media, total bacterial counts with increasing post-operative days were-amoxicillin (11 mg/kg) day 4: log 105-10-9/TNTC cfu/mL vs. day 8: log 103-105 cfu/mL; cefotaxime (25 mg/kg) day 4: log 103-108/TNTC/cfu/mL vs. day 8: log 102-105 cfu/mL; oxytetracycline (10 mg/kg) day 4: log 104-109 TNTC cfu/mL vs. day 8: log 102-106 cfu/mL. Total bacterial counts of control animals were-day 4: log 105-108/TNTC cfu/mL vs. day 8: log 105-109. Total qualitative populations of predominant, easily-recoverable aerobic and anaerobic rectal canine bacteria, Staphylococcus and lactobacilli were significantly less after gastrectomy but reductions in post-operative bacterial populations were mostly more pronounced among the anaerobes (lactobacilli and Clostridium perfringens). No post-operative infection was recorded among all the experimental animals, including the control animals. In conclusion, this study confirmed significant reduction effect of prolonged empiric antibiotic administration on rectal (intestinal) bacterial populations of experimental local dogs that had partial, non-laparoscopic gastrectomy.
    Journal of Animal and Veterinary Advances 01/2015; 7(3):40-48. · 0.37 Impact Factor
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    • "Antimicrobial prophylaxis is only one relatively minor effort among numerous preventive measures against microbial infections, and although it is not a substitute for good surgical techniques, the efficacy and impact of pre-operative and post-operative antimicrobial prophylaxis has been demonstrated to be significant (Stinner et al., 1998; Bowater et al., 2009) but timing of antibiotic administration is critical for efficacy (Wilcke, 1990; Dunning, 2003). In certain gastrointestinal procedures, oral and intravenous administration of antimicrobial agents with activity against Gram-negative and anaerobic bacteria is warranted. "
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    ABSTRACT: Reliable data that can serve as platform for policy formulation on the use of an-timicrobial drugs are compulsory for every country. But baseline data to judge effects of long-term post-operative antibiotic administration in clinical and surgical canine health conditions are currently lacking in Nigeria. This study aimed at providing vital baseline antibiotic profiles of canine bacteria of veterinary and public health importance. Phenotypic antibiotic susceptibility and resistance profiles of some easily recoverable Gram-negative bacterial species of canine origin were determined towards the most commonly prescribed and administered antibiotics in veterinary practices, using agar disk-and modified agar well-diffusion methods. Overall resistance of the bacteria against antibiotics (discs) were-tetracycline (25.0-57.1%), cotrimoxazole (80.0-100%), nitrofurantoin (20.0-100%), nalidixic acid (0.91-60.0%), gentamicin (18.2-70.0%), ofloxacillin (20.0-42.9%) and augmentin / amoxicillin (100%), except among Klebsiella pneumoniae and Proteus mirabilis (60.0-100), with percentage multiple antibiotic resistance (%MAR) of 25.0-100%. Overall percentage resistance rates towards antibiotic drugs were-amoxicillin (9.1-100%); oritaxim / oxytetracycline (20.0-100%) and nitaxim (30.0-100%), with %MAR mostly between 50.0 and 100%. Twenty eight antibiotic resistance profiles were exhibited against antibiotic (discs), commonest profiles being – augmentin-amoxicillin-cotrimoxazole; augmentin-tetracycline-amoxicillin-cotrimoxazole-ni-trofurantoin-nalidixic acid-gentamicin-ofloxacillin; augmentin-tetracycline-amox-icillin-cotrimoxazole and augmentin-amoxicillin-cotrimoxazole-nitrofurantoin. Twelve antibiotic resistance profiles were exhibited against the antibiotic drugs, with most-resisted / commonest profile being – oritaxim-nitaxim. These were also the most-resisted nitaxim (47.3%) and oritaxim (52.7%) antibiotic drugs. Only
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    • "Antibiotic prophylaxis has been recognised as an effective intervention to reduce postoperative SSI occurrence in various types of surgery [4] [8] [16] [26]. In ORIF procedures, the metal implants used for internal fixation and the periprosthetic environment (e.g., biofilm formation) can significantly increase the probability of SSI. "
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    ABSTRACT: Background: Widespread overuse and inappropriate use of antibiotics contribute to increasingly antibiotic-resistant pathogens and higher health care costs. It is not clear whether routine antibiotic prophylaxis can reduce the rate of surgical site infection (SSI) in low-risk patients undergoing orthopaedic surgery. We designed a simple scorecard to grade SSI risk factors and determined whether routine antibiotic prophylaxis affects SSI occurrence during open reduction and internal fixation (ORIF) orthopaedic surgeries in trauma patients at low risk of developing SSI. Methods: The SSI risk scorecard (possible total points ranged from 5 to 25) was designed to take into account a patient's general health status, the primary cause of fractures, surgical site tissue condition or wound class, types of devices implanted, and surgical duration. Patients with a low SSI risk score (≤8 points) who were undergoing clean ORIF surgery were divided into control (routine antibiotic treatment, cefuroxime) and evaluation (no antibiotic treatment) groups and followed up for 13-17 months after surgery. Results: The infection rate was much higher in patients with high SSI risk scores (≥9 points) than in patients with low risk scores assigned to the control group (10.7% vs. 2.2%, P<0.0001). SSI occurred in 11 of 499 patients in the control group and in 13 of 534 patients in the evaluation group during the follow-up period of 13-17 months. The SSI occurrence rate did not differ significantly (2.2% vs. 2.4%, P=0.97) between the control and evaluation groups. Conclusions: Routine antibiotic prophylaxis does not significantly decrease the rate of SSI in ORIF surgical patients with a low risk score. Implementation of this scoring system could guide the rational use of perioperative antibiotics and ultimately reduce antibiotic resistance, health care costs, and adverse reactions to antibiotics.
    Injury 08/2014; 46(2). DOI:10.1016/j.injury.2014.07.026 · 2.14 Impact Factor
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