Surgery contaminated operations

Surgical procedures that necessitate the use of antimicrobial prophylaxis include contaminated and clean-contaminated operations, selected operations in which postoperative infection may be catastrophic such as open heart surgery, clean procedures that involve placement of prosthetic materials, and any procedure in an immunocompromised host. The operation should carry a significant risk of postoperative site infection or cause significant bacterial contamination. 

Contaminated surgery Long operative procedure Trauma with delayed treatment Necrotic tissue or foreign body s Necrotic tissue or foreign body Prolonged duration Large in size and/or deep Anatomically situated near a site of potential contamination, e.g. anal area... 

Bernard HR, Cole WR. The prophylaxis of surgical infection the effect of prophylactic antimicrobial drugs on the incidence of infection following potentially contaminated operations. Surgery 1964 156 151-157. 

The Study on the Efficacy of Nosocomial Infection Control (SENIC) analyzed more than 100,000 surgery cases and identified abdominal operations, operations lasting more than 2 hours, contaminated or dirty procedures, and more than three underlying medical diagnoses as factors associated with an increased incidence of SSI. When the NRC classification described in Table 48-1 was stratified by the number of SENIC risk factors present, the infection rates varied by as much as a factor of 15 within the same operative category. 

Gas gangrene. The skin between the waist and the knees is normally contaminated with anaerobic faecal organisms. However assiduous the skin preparation for orthopaedic operations or thigh amputations, this will not kill or remove all the spores. Surgery done for vascular insufficiency where tissue oxygenation may be poor is likely to be followed by infection. Gas gangrene (Clostridium perfringens) may occur it may be prevented by benzylpenicillin or metronidazole prophylaxis. 

Clean-contaminated sites alimentary, genital, respiratory, or urinary operative sites that are without unusual contamination. Specifically, surgery involving the appendix, biliary tract, vagina, or oropharynx are categorized in this group. 

Brote and Nilehn [32], Jepsen [36], and Thomsen et al. [37] concluded that the post-operative contamination of the surgical wound may not be as important as previously believed. The resident flora of the patient present at the end of surgery may be a primary source of contamination. The authors stated that only a few organisms are transferred to the wound during surgery. (There is a theoretical difference of opinion here.) Dr. Rhodeheaver of the University of Virginia Medical School states that, under occlusive dressings, the surface of the wound may be bathed with bacteria-laden fluid. 

The assessment of colon proximal to an obstructing colonic mass has been a shortcoming of conventional colonoscopy. In the past, inter-operative palpation or post-operative colonoscopy was performed with the possibility of a second surgery required for a missed synchronous cancer or adenoma. The sensitivity of hand palpation is fairly low and intraoperative insufflation of the colon increases the risk of peritoneal contamination. 

Double contrast barium enema remains in the algorithm for work-up of colorectal cancer in evaluation of the proximal bowel in cases of an obstructing mass. This examination is not preferred, as the proximal colon often does not drain all of the barium by the time of surgery. Patients are also at increased risk for post-operative morbidity if a reactive peritonitis develops secondary to barium contamination intr a- operatively. 

Laboratory shoes or shoe covers (Figure 2.6) are used to reduce the transfer of contamination into the laboratory and to reduce the chance of carrying hazardous agents out of the laboratory on the shoes. In the biomedical laboratory, shoe covers typically are used in animal surgery and during ultraclean laboratory operations. Shoe covers may also be required in chemical carcinogenesis laboratory operations. Keep in mind that sandals do not provide any foot protection whatever and must not be worn while working in the laboratory. 

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